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Network Working Group                                        A. Siddiqui
Request for Comments: 4712                                  D. Romascanu
Category: Standards Track                                          Avaya
                                                           E. Golovinsky
                                                             Alert Logic
                                                               M. Rahman
                                     Samsung Information Systems America
                                                                  Y. Kim
                                                                Broadcom
                                                            October 2006


    Transport Mappings for Real-time Application Quality-of-Service
              Monitoring (RAQMON) Protocol Data Unit (PDU)

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2006).

Abstract

   This memo specifies two transport mappings of the Real-Time
   Application Quality-of-Service Monitoring (RAQMON) information model
   defined in RFC 4710 using TCP as a native transport and the Simple
   Network Management Protocol (SNMP) to carry the RAQMON information
   from a RAQMON Data Source (RDS) to a RAQMON Report Collector (RRC).

















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Table of Contents

   1. Introduction ....................................................3
   2. Transporting RAQMON Protocol Data Units .........................3
      2.1. TCP as an RDS/RRC Network Transport Protocol ...............3
           2.1.1. The RAQMON PDU ......................................5
           2.1.2. The BASIC Part of the RAQMON Protocol Data Unit .....7
           2.1.3. APP Part of the RAQMON Protocol Data Unit ..........14
           2.1.4. Byte Order, Alignment, and Time Format of
                  RAQMON PDUs ........................................15
      2.2. Securing RAQMON Session ...................................15
           2.2.1. Sequencing of the Start TLS Operation ..............18
           2.2.2. Closing a TLS Connection ...........................21
      2.3. SNMP Notifications as an RDS/RRC Network Transport
           Protocol ..................................................22
   3. IANA Considerations ............................................38
   4. Congestion-Safe RAQMON Operation ...............................38
   5. Acknowledgements ...............................................39
   6. Security Considerations ........................................39
      6.1. Usage of TLS with RAQMON ..................................41
           6.1.1. Confidentiality & Message Integrity ................41
           6.1.2. TLS CipherSuites ...................................41
           6.1.3. RAQMON Authorization State .........................42
   7. References .....................................................43
      7.1. Normative References ......................................43
      7.2. Informative References ....................................44
   Appendix A. Pseudocode ............................................46
























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1.  Introduction

   The Real-Time Application QoS Monitoring (RAQMON) Framework, as
   outlined by [RFC4710], extends the Remote Monitoring family of
   protocols (RMON) by defining entities such as RAQMON Data Sources
   RDS) and RAQMON Report Collectors (RRC) to perform various
   application monitoring in real time.  [RFC4710] defines the relevant
   metrics for RAQMON monitoring carried by the common protocol data
   unit (PDU) used between a RDS and RRC to report QoS statistics.  This
   memo contains a syntactical description of the RAQMON PDU structure.

   The following sections of this memo contain detailed specifications
   for the usage of TCP and SNMP to carry RAQMON information.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Transporting RAQMON Protocol Data Units

   The RAQMON Protocol Data Unit (PDU) utilizes a common data format
   understood by the RDS and the RRC.  A RAQMON PDU does not transport
   application data but rather occupies the place of a payload
   specification at the application layer of the protocol stack.  As
   part of the specification, this memo also specifies the usage of TCP
   and SNMP as underlying transport protocols to carry RAQMON PDUs
   between RDSs and RRCs.  While two transport protocol choices have
   been provided as options to chose from for RDS implementers, RRCs
   MUST implement the TCP transport and MAY implement the SNMP
   transport.

2.1.  TCP as an RDS/RRC Network Transport Protocol

   A transport binding using TCP is included within the RAQMON
   specification to facilitate reporting from various types of embedded
   devices that run applications such as Voice over IP, Voice over
   Wi-Fi, Fax over IP, Video over IP, Instant Messaging (IM), E-mail,
   software download applications, e-business style transactions, web
   access from wired or wireless computing devices etc.  For many of
   these devices, PDUs and a TCP-based transport fit the deployment
   needs.

   The RAQMON transport requirements for end-to-end congestion control
   and reliability are inherently built into TCP as a transport protocol
   [RFC793].






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   To use TCP to transport RAQMON PDUs, it is sufficient to send the
   PDUs as TCP data.  As each PDU carries its length, the receiver can
   determine the PDU boundaries.

   The following section details the RAQMON PDU specifications.  Though
   transmitted as one Protocol Data Unit, a RAQMON PDU is functionally
   divided into two different parts: the BASIC part and application
   extensions required for vendor-specific extension [RFC4710].  Both
   functional parts follow a field carrying a SMI Network Management
   Private Enterprise code currently maintained by IANA
   http://www.iana.org/assignments/enterprise-numbers, which is used to
   identify the organization that defined the information carried in the
   PDU.

   A RAQMON PDU in the current version is marked as PDU Type (PDT) = 1.
   The parameters carried by RAQMON PDUs are shown in Figure 1 and are
   defined in section 5 of [RFC4710].

   Vendors MUST use the BASIC part of the PDU to report parameters pre-
   listed here in the specification for interoperability, as opposed to
   using the application-specific portion.  Vendors MAY also use
   application-specific extensions to convey application-, vendor-, or
   device-specific parameters not included in the BASIC part of the
   specification and explicitly publish such data externally to attain
   extended interoperability.


























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2.1.1.  The RAQMON PDU

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |PDT = 1  |B|  T  |P|S|R|  RC   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            DSRC                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  SMI Enterprise Code = 0      |Report Type = 0|     RC_N      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |flag
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                   Data Source Address {DA}                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Receiver's Address (RA)                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               NTP Timestamp, most significant word            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               NTP Timestamp, least significant word           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Length       |   Application Name (AN)  ...                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Length       |   Data Source Name (DN)  ...                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Length       |    Receiver's Name (RN)  ...                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Length       |    Session State          ...                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...                                |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Session Duration                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              Round-Trip End-to-End Network Delay              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              One-Way End-to-End Network Delay                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Cumulative Packet Loss                   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              Cumulative Application Packet Discard            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |              Total # Application Packets sent                 |



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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Total # Application Packets received              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               Total # Application Octets sent                 |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             Total # Application Octets received               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Data Source Device Port Used  |  Receiver Device Port Used    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    S_Layer2   |   S_Layer3    |   S_Layer2    |   S_Layer3    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Source Payload |Receiver       | CPU           | Memory        |
   |Type           |Payload Type   | Utilization   | Utilization   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Session Setup Delay        |     Application Delay         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | IP Packet Delay Variation     |   Inter arrival Jitter        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Packet Discrd |  Packet loss  |         Padding               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  SMI Enterprise Code = "xxx"                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Report Type = "yyy"       | Length of Application Part    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               application/vendor specific extension           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...............                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...............                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...............                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                  SMI Enterprise Code = "abc"                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Report Type = "zzz"       | Length of Application Part    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |               application/vendor specific extension           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            ...............                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 1: RAQMON Protocol Data Unit









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2.1.2.  The BASIC Part of the RAQMON Protocol Data Unit

   A RAQMON PDU must contain the following BASIC part fields at all
   times:

   PDU type (PDT): 5 bits - This indicates the type of RAQMON PDU being
      sent.  PDT = 1 is used for the current RAQMON PDU version defined
      in this document.

   basic (B): 1 bit - While set to 1, the basic flag indicates that the
      PDU has BASIC part of the RAQMON PDU.  A value of zero is
      considered valid and indicates a RAQMON NULL PDU.

   trailer (T): 3 bits - Total number of Application-Specific Extensions
      that follow the BASIC part of RAQMON PDU.  A value of zero is
      considered valid as many times as there is no application-
      specific information to add to the basic information.

   padding (P): 1 bit - If the padding bit is set, the BASIC part of the
      RAQMON PDU contains some additional padding octets at the end of
      the BASIC part of the PDU that are not part of the monitoring
      information.  Padding may be needed in some cases, as reporting is
      based on the intent of a RDS to report certain parameters.  Also,
      some parameters may be reported only once at the beginning of the
      reporting session, e.g., Data Source Name, Receiver Name, payload
      type, etc.  Actual padding at the end of the BASIC part of the PDU
      is 0, 8, 16, or 24 bits to make the length of the BASIC part of
      the PDU a multiple of 32 bits

   Source IP version Flag (S): 1 bit - While set to 1, the source IP
      version flag indicates that the Source IP address contained in the
      PDU is an IPv6 address.

   Receiver IP version Flag (R): 1 bit - While set to 1, the receiver IP
      version flag indicates that the receiver IP address contained in
      the PDU is an IPv6 address.

   record count (RC): 4 bits - Total number of application records
      contained in the BASIC part of the PDU.  A value of zero is
      considered valid but useless, with the exception of the case of a
      NULL PDU indicating the end of a RDS reporting session.

   length: 16 bits (unsigned integer) - The length of the BASIC part of
      the RAQMON PDU in units of 32-bit words minus one; this count
      includes the header and any padding.






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   DSRC: 32 bits - Data Source identifier represents a unique RAQMON
      reporting session descriptor that points to a specific reporting
      session between RDS and RRC.  Uniqueness of DSRC is valid only
      within a reporting session.  DSRC values should be randomly
      generated using vendor-chosen algorithms for each communication
      session.  It is not sufficient to obtain a DSRC simply by calling
      random() without carefully initializing the state.  One could use
      an algorithm like the one defined in Appendix A.6 in [RFC3550] to
      create a DSRC.  Depending on the choice of algorithm, there is a
      finite probability that two DSRCs from two different RDSs may be
      the same.  To further reduce the probability that two RDSs pick
      the same DSRC for two different reporting sessions, it is
      recommended that an RRC use parameters like Data Source Address
      (DA), Data Source Name (DN), and layer 2 Media Access Control
      (MAC) Address in the PDU in conjunction with a DSRC value.  It is
      not mandatory for RDSs to send parameters like Data Source Address
      (DA), Data Source Name (DN), and MAC Address in every PDU sent to
      RRC, but occasionally sending these parameters will reduce the
      probability of DSRC collision drastically.  However, this will
      cause an additional overhead per PDU.

      A value of zero for basic (B) bit and trailer (T) bits constitutes
      a RAQMON NULL PDU (i.e., nothing to report).  RDSs MUST send a
      RAQMON NULL PDU to RRC to indicate the end of the RDS reporting
      session.  A NULL PDU ends with the DSRC field.

   SMI Enterprise Code: 16 bits.  A value of SMI Enterprise Code = 0 is
      used to indicate the RMON-WG-compliant BASIC part of the RAQMON
      PDU format.

   Report Type: 8 bits - These bits are reserved by the IETF RMON
      Working Group.  A value of 0 within SMI Enterprise Code = 0 is
      used for the version of the PDU defined by this document.

      The BASIC part of each RAQMON PDU consists of Record Count Number
      (RC_N) and RAQMON Parameter Presence Flags (RPPF) to indicate the
      presence of appropriate RAQMON parameters within a record, as
      defined in Table 1.

   RC_N: 8 bits - The Record Count number indicates a sub-session within
      a communication session.  A value of zero is a valid record
      number.  The maximum number of records that can be described in
      one RAQMON Packet is 256.

   RAQMON Parameter Presence Flags (RPPF): 32 bits

      Each of these flags, while set, represents that this RAQMON PDU
      contains corresponding parameters as specified in Table 1.



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   +----------------+--------------------------------------------------+
   |  Bit Sequence  |    Presence/Absence of corresponding Parameter   |
   |     Number     |              within this RAQMON PDU              |
   +----------------+--------------------------------------------------+
   |        0       |             Data Source Address (DA)             |
   |                |                                                  |
   |        1       |               Receiver Address (RA)              |
   |                |                                                  |
   |        2       |                   NTP Timestamp                  |
   |                |                                                  |
   |        3       |                 Application Name                 |
   |                |                                                  |
   |        4       |               Data Source Name (DN)              |
   |                |                                                  |
   |        5       |                Receiver Name (RN)                |
   |                |                                                  |
   |        6       |               Session Setup Status               |
   |                |                                                  |
   |        7       |                 Session Duration                 |
   |                |                                                  |
   |        8       |       Round-Trip End-to-End Net Delay (RTT)      |
   |                |                                                  |
   |        9       |      One-Way End-to-End Network Delay (OWD)      |
   |                |                                                  |
   |       10       |              Cumulative Packets Loss             |
   |                |                                                  |
   |       11       |            Cumulative Packets Discards           |
   |                |                                                  |
   |       12       |         Total number of App Packets sent         |
   |                |                                                  |
   |       13       |       Total number of App Packets received       |
   |                |                                                  |
   |       14       |          Total number of App Octets sent         |
   |                |                                                  |
   |       15       |        Total number of App Octets received       |
   |                |                                                  |
   |       16       |           Data Source Device Port Used           |
   |                |                                                  |
   |       17       |             Receiver Device Port Used            |
   |                |                                                  |
   |       18       |              Source Layer 2 Priority             |
   |                |                                                  |
   |       19       |              Source Layer 3 Priority             |
   |                |                                                  |
   |       20       |           Destination Layer 2 Priority           |
   |                |                                                  |
   |       21       |           Destination Layer 3 Priority           |
   |                |                                                  |



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   |       22       |                Source Payload Type               |
   |                |                                                  |
   |       23       |               Receiver Payload Type              |
   |                |                                                  |
   |       24       |                  CPU Utilization                 |
   |                |                                                  |
   |       25       |                Memory Utilization                |
   |                |                                                  |
   |       26       |                Session Setup Delay               |
   |                |                                                  |
   |       27       |                 Application Delay                |
   |                |                                                  |
   |       28       |             IP Packet Delay Variation            |
   |                |                                                  |
   |       29       |               Inter arrival Jitter               |
   |                |                                                  |
   |       30       |           Packet Discard (in fraction)           |
   |                |                                                  |
   |       31       |             Packet Loss (in fraction)            |
   +----------------+--------------------------------------------------+

             Table 1: RAQMON Parameters and Corresponding RPPF

   Data Source Address (DA): 32 bits or 160 bits in binary
      representation - This parameter is defined in section 5.1 of
      [RFC4710].  IPv6 addresses are incorporated in Data Source Address
      by setting the source IP version flag (S bit) of the RAQMON PDU
      header to 1.

   Receiver Address (RA): 32 bits or 160 bits - This parameter is
      defined in section 5.2 of [RFC4710].  It follows the exact same
      syntax as Data Source Address but is used to indicate a Receiver
      Address.  IPv6 addresses are incorporated in Receiver Address by
      setting the receiver IP version flag (R bit) of the RAQMON PDU
      header to 1.

   Session Setup Date/Time (NTP timestamp): 64 bits - This parameter is
      defined in section 5.7 of [RFC4710] and represented using the
      timestamp format of the Network Time Protocol (NTP), which is in
      seconds [RFC1305].  The full resolution NTP timestamp is a 64-bit
      unsigned fixed-point number with the integer part in the first 32
      bits and the fractional part in the last 32 bits.

   Application Name: This parameter is defined in section 5.32 of
      [RFC4710].  The Application Name field starts with an 8-bit octet
      count describing the length of the text followed by the text
      itself using UTF-8 encoding.  Application Name field is a multiple
      of 32 bits, and padding will be used if necessary.



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      A Data Source that does not support NTP SHOULD set the appropriate
      RAQMON flag to 0 to avoid wasting 64 bits in the PDU.  Since the
      NTP time stamp is intended to provide the setup Date/Time of a
      session, it is RECOMMENDED that the NTP Timestamp be used only in
      the first RAQMON PDU after sub-session RC_N setup is completed, in
      order to use network resources efficiently.

   Data Source Name (DN): Defined in section 5.3 of [RFC4710].  The Data
      Source Name field starts with an 8-bit octet count describing the
      length of the text followed by the text itself.  Padding is used
      to ensure that the length and text encoding occupy a multiple of
      32 bits in the DN field of the PDU.  The text MUST NOT be longer
      than 255 octets.  The text is encoded according to the UTF-8
      encoding specified in [RFC3629].  Applications SHOULD instruct
      RDSs to send out the Data Source Name infrequently to ensure
      efficient usage of network resources as this parameter is expected
      to remain constant for the duration of the reporting session.

   Receiver Name (RN): This metric is defined in section 5.4 of
      [RFC4710].  Like Data Source Name, the Receiver Name field starts
      with an 8-bit octet count describing the length of the text,
      followed by the text itself.  The Receiver Name, including the
      length field encoding, is a multiple of 32 bits and follows the
      same padding rules as applied to the Data Source Name.  Since the
      Receiver Name is expected to remain constant during the entire
      reporting session, this information SHOULD be sent out
      occasionally over random time intervals to maximize success of
      reaching a RRC and also conserve network bandwidth.

   Session Setup Status: The Session (sub-session) Setup Status is
      defined in section 5.10 of [RFC4710].  This field starts with an
      8-bit length field followed by the text itself.  Session Setup
      Status is a multiple of 32 bits.

   Session Duration: 32 bits - The Session (sub-session) Duration metric
      is defined in section 5.9 of [RFC4710].  Session Duration is an
      unsigned integer expressed in seconds.

   Round-Trip End-to-End Network Delay: 32 bits - The Round-Trip End-
      to-End Network Delay is defined in section 5.11 of [RFC4710].
      This field represents the Round-Trip End-to-End Delay of sub-
      session RC_N, which is an unsigned integer expressed in
      milliseconds.

   One-Way End-to-End Network Delay: 32 bits - The One-Way End-to-End
      Network Delay is defined in section 5.12 of [RFC4710].  This field
      represents the One-Way End-to-End Delay of sub-session RC_N, which
      is an unsigned integer expressed in milliseconds.



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   Cumulative Application Packet Loss: 32 bits - This parameter is
      defined in section 5.20 of [RFC4710] as an unsigned integer,
      representing the total number of packets from sub-session RC_N
      that have been lost while this RAQMON PDU was generated.

   Cumulative Application Packet Discards: 32 bits - This parameter is
      defined in section 5.22 of [RFC4710] as an unsigned integer
      representing the total number of packets from sub-session RC_N
      that have been discarded while this RAQMON PDU was generated.

   Total number of Application Packets sent: 32 bits - This parameter is
      defined in section 5.17 of [RFC4710] as an unsigned integer,
      representing the total number of packets transmitted within sub-
      session RC_N by the sender.

   Total number of Application Packets received: 32 bits - This
      parameter is defined in section 5.16 of [RFC4710] and is
      represented as an unsigned integer representing the total number
      of packets transmitted within sub-session RC_N by the receiver.

   Total number of Application Octets sent: 32 bits - This parameter is
      defined in section 5.19 of [RFC4710] as an unsigned integer,
      representing the total number of payload octets (i.e., not
      including header or padding) transmitted in packets by the sender
      within sub-session RC_N.

   Total number of Application Octets received: 32 bits - This parameter
      is defined in section 5.18 of [RFC4710] as an unsigned integer
      representing the total number of payload octets (i.e., not
      including header or padding) transmitted in packets by the
      receiver within sub-session RC_N.

   Data Source Device Port Used: 16 bits - This parameter is defined in
      section 5.5 of [RFC4710] and describes the port number used by the
      Data Source as used by the application in RC_N session while this
      RAQMON PDU was generated.

   Receiver Device Port Used: 16 bits - This parameter is defined in
      section 5.6 of [RFC4710] and describes the receiver port used by
      the application to communicate to the receiver.  It follows same
      syntax as Source Device Port Used.

   S_Layer2: 8 bits - This parameter, defined in section 5.26 of
      [RFC4710], is associated to the source's IEEE 802.1D [IEEE802.1D]
      priority tagging of traffic in the communication sub-session RC_N.
      Since IEEE 802.1 priority tags are 3 bits long, the first 3 bits
      of this parameter represent the IEEE 802.1 tag value, and the last
      5 bits are padded to 0.



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   S_Layer3: 8 bits - This parameter, defined in section 5.27 of
      [RFC4710], represents the layer 3 QoS marking used to send packets
      to the receiver by this data source during sub-session RC_N.

   D_Layer2: 8 bits - This parameter, defined in section 5.28 of
      [RFC4710], represents layer 2 IEEE 802.1D priority tags used by
      the receiver to send packets to the data source during sub-session
      RC_N session if the Data Source can learn such information.  Since
      IEEE 802.1 priority tags are 3 bits long, the first 3 bits of this
      parameter represent the IEEE 802.1 priority tag value, and the
      last 5 bits are padded to 0.

   D_Layer3: 8 bits - This parameter is defined in section 5.29 of
      [RFC4710] and represents the layer 3 QoS marking used by the
      receiver to send packets to the data source during sub-session
      RC_N, if the Data Source can learn such information.

   Source Payload Type: 8 bits - This parameter is defined in section
      5.24 of [RFC4710] and specifies the payload type of the data
      source of the communication sub-session RC_N as defined in
      [RFC3551].

   Receiver Payload Type: 8 bits - This parameter is defined in section
      5.25 of [RFC4710] and specifies the receiver payload type of the
      communication sub-session RC_N as defined in [RFC3551].

   CPU Utilization: 8 bits - This parameter, defined in section 5.30 of
      [RFC4710], represents the percentage of CPU used during session
      RC_N from the last report until the time this RAQMON PDU was
      generated.  The CPU Utilization is expressed in percents in the
      range 0 to 100.  The value should indicate not only CPU
      utilization associated to a session RC_N but also actual CPU
      Utilization, to indicate a snapshot of the CPU utilization of the
      host running the RDS while session RC_N in progress.

   Memory Utilization: 8 bits - This parameter, defined in section 5.31
      of [RFC4710], represents the percentage of total memory used
      during session RC_N up until the time this RAQMON PDU was
      generated.  The memory utilization is expressed in percents 0 to
      100.  The Memory Utilization value should indicate not only the
      memory utilization associated to a session RC_N but the total
      memory utilization, to indicate a snapshot of end-device memory
      utilization while session RC_N is in progress.

   Session Setup Delay: 16 bits - The Session (sub-session) Setup Delay
      metric is defined in section 5.8 of [RFC4710] and expressed in
      milliseconds.




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   Application Delay: 16 bits - The Application Delay is defined in
      section 5.13 of [RFC4710] and is represented as an unsigned
      integer expressed in milliseconds.

   IP Packet Delay Variation: 16 bits - The IP Packet Delay Variation is
      defined in section 5.15 of [RFC4710] and is represented as an
      unsigned integer expressed in milliseconds.

   Inter-Arrival Jitter: 16 bits - The Inter-Arrival Jitter is defined
      in section 5.14 of [RFC4710] and is represented as an unsigned
      integer expressed in milliseconds.

   Packet Discard in Fraction: 8 bits - This parameter is defined in
      section 5.23 of [RFC4710] and is expressed as a fixed-point number
      with the binary point at the left edge of the field.  (That is
      equivalent to taking the integer part after multiplying the
      discard fraction by 256.)  This metric is defined to be the number
      of packets discarded, divided by the total number of packets.

   Packet Loss in Fraction: 8 bits - This parameter is defined in
      section 5.21 of [RFC4710] and is expressed as a fixed-point
      number, with the binary point at the left edge of the field.  The
      metric is defined to be the number of packets lost divided by the
      number of packets expected.  The value is calculated by dividing
      the total number of packets lost (after the effects of applying
      any error protection, such as Forward Error Correction (FEC)) by
      the total number of packets expected, multiplying the result of
      the division by 256, limiting the maximum value to 255 (to avoid
      overflow), and taking the integer part.

   padding: 0, 8, 16, or 24 bits - If the padding bit (P) is set, then
      this field may be present.  The actual padding at the end of the
      BASIC part of the PDU is 0, 8, 16, or 24 bits to make the length
      of the BASIC part of the PDU a multiple of 32 bits.

2.1.3.  APP Part of the RAQMON Protocol Data Unit

   The APP part of the RAQMON PDU is intended to accommodate extensions
   for new applications in a modular manner and without requiring a PDU
   type value registration.

   Vendors may design and publish application-specific extensions.  Any
   RAQMON-compliant RRC MUST be able to recognize vendors' SMI
   Enterprise Codes and MUST recognize the presence of application-
   specific extensions identified by using Report Type fields.  As
   represented in Figure 1, the Report Type and Application Length





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   fields are always located at a fixed offset relative to the start of
   the extension fields.  There is no need for the RRC to understand the
   semantics of the enterprise-specific parts of the PDU.

   SMI Enterprise Code: 32 bits - Vendors and application developers
      should fill in appropriate SMI Enterprise IDs available at
      http://www.iana.org/assignments/enterprise-numbers.  A non-zero
      SMI Enterprise Code indicates a vendor- or application-specific
      extension.

      RAQMON PDUs are capable of carrying multiple Application Parts
      within a PDU.

   Report Type: 16 bits - Vendors and application developers should fill
      in the appropriate report type within a specified SMI Enterprise
      Code.  It is RECOMMENDED that vendors publish application-specific
      extensions and maintain such report types for better
      interoperability.

   Length of the Application Part: 16 bits (unsigned integer) - The
      length of the Application Part of the RAQMON PDU in 32-bit words
      minus one, which includes the header of the Application Part.

   Application-dependent data: variable length - Application/
      vendor-dependent data is defined by the application developers.
      It is interpreted by the vendor-specific application and not by
      the RRC itself.  Its length must be a multiple of 32 bits and will
      be padded if necessary.

2.1.4.  Byte Order, Alignment, and Time Format of RAQMON PDUs

   All integer fields are carried in network byte order, that is, most
   significant byte (octet) first.  This byte order is commonly known as
   big-endian.  The transmission order is described in detail in
   [RFC791].  Unless otherwise noted, numeric constants are in decimal
   (base 10).

   All header data is aligned to its natural length, i.e., 16-bit fields
   are aligned on even offsets, 32-bit fields are aligned at offsets
   divisible by four, etc.  Octets designated as padding have the value
   zero.

2.2.  Securing RAQMON Session

   The RAQMON session, initiated over TCP transport, between an RDS and
   an RRC carries monitoring information from an RDS client to the RRC,
   the collector.  The RRC distinguishes between clients based on
   various identifiers used by the RDS to identify itself to the RRC



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   (Data Source Address and Data Source Name) and the RRC (Receiver's
   Address and Receiver's Name).

   In order to ensure integrity of the claimed identities of RDS and RRC
   to each other, authentication services are required.

   Subsequently, where protection from unauthorized modification and
   unauthorized disclosure of RAQMON data in transit from RDS to RRC is
   needed, data confidentiality and message integrity services will be
   required.  In order to prevent monitoring-misinformation due to
   session-recording and replay by unauthorized sources, replay
   protection services may be required.

   TLS provides, at the transport layer, the required authentication
   services through the handshake protocol and subsequent data
   confidentiality, message integrity, and replay protection of the
   application protocol using a ciphersuite negotiated during
   authentication.

   The RDS client authenticates the RRC in session.  The RRC optionally
   authenticates the RDS.

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |PDT = 1  |B|  T  |P|S|R|  RC   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            DSRC                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  SMI Enterprise Code = 0      |Report Type =  |     RC_N      |
   |                               |        TLS_REQ|               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                Figure 2: RAQMON StartTLS Request - TLS_REQ

   The protection of a RAQMON session starts with the RDS client's
   StartTLS request upon successful establishment of the TCP session.
   The RDS sends the StartTLS request by transmitting the TLS_REQ PDU as
   in Figure 2.  This PDU is distinguished by TLS_REQ Report Type.

   Following this request, the client MUST NOT send any PDUs on this
   connection until it receives a StartTLS response.

   Other fields of the PDU are as specified in Figure 1.

   The flags field do not carry any significance and exist for
   compatibility with the generic RAQMON PDU.  The flags field in this
   version MUST be ignored.



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   When a StartTLS request is made, the target server, RRC, MUST return
   a RAQMON PDU containing a StartTLS response, TLS_RESP.  A RAQMON
   TLS_RESP is defined as follows:

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |PDT = 1  |B|  T  |P|S|R|  RC   |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            DSRC                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  SMI Enterprise Code = 0      |Report Type =  |     Result    |
   |                               |       TLS_RESP|               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 3: RAQMON StartTLS Response - TLS_RESP

   The RRC responds to the StartTLS request by transmitting the TLS_RESP
   PDU as in Figure 3.  This PDU is distinguished by TLS_RESP Report
   Type.

   The Result field is an octet containing the result of the request.
   This field can carry one of the following values:

   +-------+------------------+----------------------------------------+
   | Value |     Mnemonic     |                 Result                 |
   +-------+------------------+----------------------------------------+
   |   0   |        OK        |   Success.  The server is willing and  |
   |       |                  |         able to negotiate TLS.         |
   |   1   |      OP_ERR      |   Sequencing Error (e.g., TLS already  |
   |       |                  |              established).             |
   |   2   |     PROTO_ERR    |   TLS not supported or incorrect PDU   |
   |       |                  |                 format.                |
   |   3   |      UNAVAIL     |    TLS service problem or RRC server   |
   |       |                  |               going down.              |
   |   4   |     CONF_REQD    |    Confidentiality Service Required.   |
   |       |                  |                                        |
   |   5   | STRONG_AUTH_REQD |      Strong Authentication Service     |
   |       |                  |                Required.               |
   |   6   |     REFERRAL     |   Referral to a RRC Server supporting  |
   |       |                  |                  TLS.                  |
   +-------+------------------+----------------------------------------+

                                  Table 2

   Other fields of the PDU are as specified in Figure 1.





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   The server MUST return OP_ERR if the client violates any of the
   StartTLS operation sequencing requirements described in the section
   below.

   If the server does not support TLS (whether by design or by current
   configuration), it MUST set the resultCode to PROTO_ERR or to
   REFERRAL.  The server MUST include an actual referral value in the
   RAQMON REFER field if it returns a resultCode of referral.  The
   client's current session is unaffected if the server does not support
   TLS.  The client MAY proceed with RAQMON session, or it MAY close the
   connection.

   The server MUST return UNAVAIL if it supports TLS but cannot
   establish a TLS connection for some reason, e.g., if the certificate
   server not responding, if it cannot contact its TLS implementation,
   or if the server is in process of shutting down.  The client MAY
   retry the StartTLS operation, MAY proceed with RAQMON session, or MAY
   close the connection.

2.2.1.  Sequencing of the Start TLS Operation

   This section describes the overall procedures clients and servers
   MUST follow for TLS establishment.  These procedures take into
   consideration various aspects of the overall security of the RAQMON
   connection including discovery of resulting security level.

2.2.1.1.  Requesting to Start TLS on a RAQMON Association

   The client MAY send the StartTLS request at any time after
   establishing an RAQMON (TCP) connection, except that in the following
   cases the client MUST NOT send a StartTLS request:

   o  if TLS is currently established on the connection, or

   o  if RAQMON traffic is in progress on the connection.

   The result of violating any of these requirements is a Result of
   OP_ERR, as described above in Table 2.

   If the client did not establish a TLS connection before sending any
   other requests, and the server requires the client to establish a TLS
   connection before performing a particular request, the server MUST
   reject that request with a CONF_REQD or STRONG_AUTH_REQD result.  The
   client MAY send a Start TLS extended request, or it MAY choose to
   close the connection.






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2.2.1.2.  Starting TLS

   The server will return an extended response with the resultCode of
   success if it is willing and able to negotiate TLS.  It will return
   other resultCodes, documented above, if it is unable.

   In the successful case, the client, which has ceased to transfer
   RAQMON PDUs on the connection, MUST either begin a TLS negotiation or
   close the connection.  The client will send PDUs in the TLS Record
   Protocol directly over the underlying transport connection to the
   server to initiate TLS negotiation [TLS].

2.2.1.3.  TLS Version Negotiation

   Negotiating the version of TLS or SSL to be used is a part of the TLS
   Handshake Protocol, as documented in [TLS].  The reader is referred
   to that document for details.

2.2.1.4.  Discovery of Resultant Security Level

   After a TLS connection is established on a RAQMON connection, both
   parties MUST individually decide whether or not to continue based on
   the security assurance level achieved.  Ascertaining the TLS
   connection's assurance level is implementation dependent and is
   accomplished by communicating with one's respective local TLS
   implementation.

   If the client or server decides that the level of authentication or
   confidentiality is not high enough for it to continue, it SHOULD
   gracefully close the TLS connection immediately after the TLS
   negotiation has completed Section 2.2.2.1.

   The client MAY attempt to Start TLS again, MAY disconnect, or MAY
   proceed to send RAQMON session data, if RRC policy permits.

2.2.1.5.  Server Identity Check

   The client MUST check its understanding of the server's hostname
   against the server's identity as presented in the server's
   Certificate message, in order to prevent man-in-the-middle attacks.

   Matching is performed according to these rules:

   o  The client MUST use the server dnsNAME in the subjectAltName field
      to validate the server certificate presented.  The server dnsName
      MUST be part of subjectAltName of the server.

   o  Matching is case-insensitive.



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   o  The "*" wildcard character is allowed.  If present, it applies
      only to the left-most name component.

      For example, *.example.com would match a.example.com,
      b.example.com, etc., but not example.com.  If more than one
      identity of a given type is present in the certificate (e.g., more
      than one dNSName name), a match in any one of the set is
      considered acceptable.

   If the hostname does not match the dNSName-based identity in the
   certificate per the above check, automated clients SHOULD close the
   connection, returning and/or logging an error indicating that the
   server's identity is suspect.

   Beyond the server identity checks described in this section, clients
   SHOULD be prepared to do further checking to ensure that the server
   is authorized to provide the service it is observed to provide.  The
   client MAY need to make use of local policy information.

   We also refer readers to similar guidelines as applied for LDAP over
   TLS [RFC4513].

2.2.1.6.  Client Identity Check

   Anonymous TLS authentication helps establish a TLS RAQMON session
   that offers

   o  server-authentication in course of TLS establishment and

   o  confidentiality and replay protection of RAQMON traffic, but

   o  no protection against man-in-the-middle attacks during session
      establishment and

   o  no protection from spoofing attacks by unauthorized clients.

   The server MUST authenticate the RDS client when deployment is
   susceptible to the above threats.  This is done by requiring client
   authentication during TLS session establishment.

   In the TLS negotiation, the server MUST request a certificate.  The
   client will provide its certificate to the server and MUST perform a
   private-key-based encryption, proving it has the private key
   associated with the certificate.

   As deployments will require protection of sensitive data in transit,
   the client and server MUST negotiate a ciphersuite that contains a
   bulk encryption algorithm of appropriate strength.



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   The server MUST verify that the client's certificate is valid.  The
   server will normally check that the certificate is issued by a known
   CA, and that none of the certificates on the client's certificate
   chain are invalid or revoked.  There are several procedures by which
   the server can perform these checks.

   The server validates the certificate by the Distinguished Name of the
   RDS client entity in the Subject field of the certificate.

   A corresponding set of guidelines will apply to use of TLS-PSK modes
   [TLS-PSK] using pre-shared keys instead of client certificates.

2.2.1.7.  Refresh of Server Capabilities Information

   The client MUST refresh any cached server capabilities information
   upon TLS session establishment, such as prior RRC state related to a
   previous RAQMON session based on another DSRC.  This is necessary to
   protect against active-intermediary attacks, which may have altered
   any server capabilities information retrieved prior to TLS
   establishment.  The server MAY advertise different capabilities after
   TLS establishment.

2.2.2.  Closing a TLS Connection

2.2.2.1.  Graceful Closure

   Either the client or server MAY terminate the TLS connection on an
   RAQMON session by sending a TLS closure alert.  This will leave the
   RAQMON connection intact.

   Before closing a TLS connection, the client MUST wait for any
   outstanding RAQMON transmissions to complete.  This happens naturally
   when the RAQMON client is single-threaded and synchronous.

   After the initiator of a close has sent a closure alert, it MUST
   discard any TLS messages until it has received an alert from the
   other party.  It will cease to send TLS Record Protocol PDUs and,
   following the receipt of the alert, MAY send and receive RAQMON PDUs.

   The other party, if it receives a closure alert, MUST immediately
   transmit a TLS closure alert.  It will subsequently cease to send TLS
   Record Protocol PDUs and MAY send and receive RAQMON PDUs.









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2.2.2.2.  Abrupt Closure

   Either the client or server MAY abruptly close the entire RAQMON
   session and any TLS connection established on it by dropping the
   underlying TCP connection.  It MAY be possible for RRC to send RDS a
   disconnection notification, which allows the client to know that the
   disconnection is not due to network failure.  However, this message
   is not defined in this version.

2.3.  SNMP Notifications as an RDS/RRC Network Transport Protocol

   It was an inherent objective of the RAQMON Framework to re-use
   existing application-level transport protocols to maximize the usage
   of existing installations as well as to avoid transport-protocol-
   level complexities in the design process.  Choice of SNMP as a means
   to transport RAQMON PDU was motivated by the intent of using existing
   installed devices implementing SNMP agents as RAQMON Data Sources
   (RDSs).

   There are some potential problems with the usage of SNMP as a
   transport mapping protocol:

   o  The potential of congestion is higher than with the TCP transport,
      because of the usage of UDP at the transport layer.

   o  The encoding of the information is less efficient, and this
      results in bigger message size, which again may negatively impact
      congestion conditions and memory size requirements in the devices.

   In order to avoid these potential problems, the following
   recommendations are made:

   o  Usage of the TCP transport is RECOMMENDED in deployment over the
      SNMP transport wherever available for a pair of RDS/RRC.

   o  The usage of Inform PDUs is RECOMMENDED.

   o  The usage of Traps PDU is NOT RECOMMENDED.

   o  It is RECOMMENDED that information carried by notifications be
      maintained within the limits of the MTU size in order to avoid
      fragmentation.

   If SNMP is chosen as a mechanism to transport RAQMON PDUs, the
   following specification applies to RAQMON-related usage of SNMP:






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   o  RDSs implement the capability of embedding RAQMON parameters in
      SNMP Notifications, re-using well-known SNMP mechanisms to report
      RAQMON Statistics.  The RAQMON RDS MIB module, as specified in
      2.1.1, MUST be used in order to map the RAQMON PDUs onto the SNMP
      Notifications transport.

   o  Since RDSs are not computationally rich, and in order to keep the
      RDS realization as lightweight as possible, RDSs MAY fail to
      respond to SNMP requests like GET, SET, etc., with the exception
      of the GET and SET commands required to implement the User-Based
      Security Model (USM) defined by [RFC3414].

   o  In order to meet congestion safety requirements, SNMP INFORM PDUs
      SHOULD be used.  In case INFORM PDUs are used, RDSs MUST process
      the SNMP INFORM responses from RRCs and MUST serialize the PDU
      transmission rate, i.e., limit the number of PDUS sent in a
      specific time interval.

   o  Standard UDP port 162 SHOULD be used for SNMP Notifications.

2.3.1.  Encoding RAQMON Using the RAQMON RDS MIB Module

   The RAQMON RDS MIB module is used to map RAQMON PDUs onto SNMP
   Notifications for transport purposes.  The MIB module defines the
   objects needed for mapping the BASIC part of RAQMON PDU, defined in
   [RFC4710], as well as the Notifications themselves.  In order to
   incorporate any application-specific extensions in the Application
   (APP) part of RAQMON PDU, as defined in [RFC4710], additional
   variable bindings MAY be included in RAQMON notifications as
   described in the MIB module.

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).
   Objects in the MIB are defined using the mechanisms defined in the
   Structure of Management Information (SMI).  This memo specifies a MIB
   module that is compliant to the SMIv2, which is described in STD 58,
   [RFC2578], STD 58, [RFC2579] and STD 58, [RFC2580].









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   The following MIB module IMPORTS definitions from the following:

            SNMPv2-SMI [RFC2578]
            SNMPv2-TC [RFC2579]
            SNMPv2-CONF [RFC2580]
            RMON-MIB [RFC2819]
            DIFFSERV-DSCP-TC [RFC3289]
            SNMP-FRAMEWORK-MIB [RFC3411]
            INET-ADDRESS-MIB [RFC4001]

   It also uses REFERENCE clauses to refer to [RFC4710].

   RAQMON-RDS-MIB DEFINITIONS ::= BEGIN

      IMPORTS
          MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
          Counter32, Unsigned32
              FROM SNMPv2-SMI

          DateAndTime
              FROM SNMPv2-TC

          rmon
              FROM RMON-MIB

          SnmpAdminString
              FROM SNMP-FRAMEWORK-MIB

          InetAddressType, InetAddress, InetPortNumber
              FROM INET-ADDRESS-MIB

          Dscp
              FROM DIFFSERV-DSCP-TC

          MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
              FROM SNMPv2-CONF;

      raqmonDsMIB MODULE-IDENTITY
          LAST-UPDATED "200610100000Z"      -- October 10, 2006
          ORGANIZATION "RMON Working Group"
          CONTACT-INFO
              "WG EMail: rmonmib@ietf.org
               Subscribe: rmonmib-request@ietf.org

               MIB Editor:
               Eugene Golovinsky
               Postal: BMC Software, Inc.
                       2101 CityWest Boulevard,



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                       Houston, TX, 77094
                       USA
               Tel:    +713-918-1816
               Email:  egolovin@bmc.com
              "
          DESCRIPTION
              "This is the RAQMON Data Source notification MIB Module.
               It provides a mapping of RAQMON PDUs to SNMP
               notifications.

               Ds stands for data source.

               Note that all of the object types defined in this module
               are accessible-for-notify and would consequently not be
               available to a browser using simple Get, GetNext, or
               GetBulk requests.

               Copyright (c) The Internet Society (2006).

               This version of this MIB module is part of RFC 4712;
               See the RFC itself for full legal notices."

          REVISION      "200610100000Z"     -- October 10, 2006
          DESCRIPTION
              "Initial version, published as RFC 4712."

                 ::= { rmon 32 }

   -- This OID allocation conforms to [RFC3737]


      raqmonDsNotifications OBJECT IDENTIFIER ::= { raqmonDsMIB 0 }
      raqmonDsMIBObjects OBJECT IDENTIFIER ::= { raqmonDsMIB 1 }
      raqmonDsConformance OBJECT IDENTIFIER ::= { raqmonDsMIB 2 }

      raqmonDsNotificationTable OBJECT-TYPE
          SYNTAX SEQUENCE OF RaqmonDsNotificationEntry
          MAX-ACCESS not-accessible
          STATUS     current
          DESCRIPTION
              "This conceptual table provides the SNMP mapping of
               the RAQMON BASIC PDU.  It is indexed by the RAQMON
               Data Source, sub-session, and address of the peer
               entity.

               Note that there is no concern about the indexation of
               this table exceeding the limits defined by RFC 2578
               Section 3.5.  According to [RFC4710], Section 5.1,



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               only IPv4 and IPv6 addresses can be reported as
               participant addresses."
          ::= { raqmonDsMIBObjects 1 }

      raqmonDsNotificationEntry OBJECT-TYPE
          SYNTAX     RaqmonDsNotificationEntry
          MAX-ACCESS not-accessible
          STATUS     current
          DESCRIPTION
              "The entry (row) is not retrievable and is not kept by
               RDSs.  It serves data organization purposes only."
          INDEX { raqmonDsDSRC, raqmonDsRCN, raqmonDsPeerAddrType,
                  raqmonDsPeerAddr }
          ::= { raqmonDsNotificationTable 1 }

      RaqmonDsNotificationEntry ::= SEQUENCE {
              raqmonDsDSRC                      Unsigned32,
              raqmonDsRCN                       Unsigned32,
              raqmonDsPeerAddrType              InetAddressType,
              raqmonDsPeerAddr                  InetAddress,
              raqmonDsAppName                   SnmpAdminString,
              raqmonDsDataSourceDevicePort      InetPortNumber,
              raqmonDsReceiverDevicePort        InetPortNumber,
              raqmonDsSessionSetupDateTime      DateAndTime,
              raqmonDsSessionSetupDelay         Unsigned32,
              raqmonDsSessionDuration           Unsigned32,
              raqmonDsSessionSetupStatus        SnmpAdminString,
              raqmonDsRoundTripEndToEndNetDelay Unsigned32,
              raqmonDsOneWayEndToEndNetDelay    Unsigned32,
              raqmonDsApplicationDelay          Unsigned32,
              raqmonDsInterArrivalJitter        Unsigned32,
              raqmonDsIPPacketDelayVariation    Unsigned32,
              raqmonDsTotalPacketsReceived      Counter32,
              raqmonDsTotalPacketsSent          Counter32,
              raqmonDsTotalOctetsReceived       Counter32,
              raqmonDsTotalOctetsSent           Counter32,
              raqmonDsCumulativePacketLoss      Counter32,
              raqmonDsPacketLossFraction        Unsigned32,
              raqmonDsCumulativeDiscards        Counter32,
              raqmonDsDiscardsFraction          Unsigned32,
              raqmonDsSourcePayloadType         Unsigned32,
              raqmonDsReceiverPayloadType       Unsigned32,
              raqmonDsSourceLayer2Priority      Unsigned32,
              raqmonDsSourceDscp                Dscp,
              raqmonDsDestinationLayer2Priority Unsigned32,
              raqmonDsDestinationDscp           Dscp,
              raqmonDsCpuUtilization            Unsigned32,
              raqmonDsMemoryUtilization         Unsigned32 }



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      raqmonDsDSRC OBJECT-TYPE
          SYNTAX     Unsigned32
          MAX-ACCESS not-accessible
          STATUS     current
          DESCRIPTION
              "Data Source identifier represents a unique session
               descriptor that points to a specific session
               between communicating entities.  Identifiers unique for
               sessions conducted between two entities are
               generated by the communicating entities.  Zero is a
               valid value, with no special semantics."
          ::= { raqmonDsNotificationEntry 1 }

      raqmonDsRCN OBJECT-TYPE
           SYNTAX      Unsigned32 (0..15)
           MAX-ACCESS  not-accessible
           STATUS      current
           DESCRIPTION
               "The Record Count Number indicates a sub-session
                within a communication session.  A maximum number of 16
                sub-sessions are supported; this limitation is
                dictated by reasons of compatibility with other
                transport protocols."
           ::= { raqmonDsNotificationEntry 2 }

      raqmonDsPeerAddrType OBJECT-TYPE
          SYNTAX InetAddressType
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
              "The type of the Internet address of the peer participant
               for this session."
          REFERENCE
              "Section 5.2 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 3 }

      raqmonDsPeerAddr OBJECT-TYPE
          SYNTAX InetAddress
          MAX-ACCESS not-accessible
          STATUS current
          DESCRIPTION
              "The Internet Address of the peer participant for this
               session."
          REFERENCE
              "Section 5.2 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 4 }

      raqmonDsAppName  OBJECT-TYPE



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          SYNTAX     SnmpAdminString
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "This is a text string giving the name and possibly the
               version of the application associated with that session,
               e.g., 'XYZ VoIP Agent 1.2'."
          REFERENCE
              "Section 5.28 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 5 }

      raqmonDsDataSourceDevicePort OBJECT-TYPE
          SYNTAX     InetPortNumber
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The port number from which data for this session was sent
               by the Data Source device."
          REFERENCE
              "Section 5.5 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 6 }

      raqmonDsReceiverDevicePort OBJECT-TYPE
          SYNTAX     InetPortNumber
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The port number where the data for this session was
               received."
          REFERENCE
              "Section 5.6 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 7 }

      raqmonDsSessionSetupDateTime OBJECT-TYPE
          SYNTAX     DateAndTime
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The time when session was initiated."
          REFERENCE
              "Section 5.7 of [RFC4710]"
      ::= { raqmonDsNotificationEntry 8 }

      raqmonDsSessionSetupDelay OBJECT-TYPE
          SYNTAX     Unsigned32 (0..65535)
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current



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          DESCRIPTION
              "Session setup time."
          REFERENCE
              "Section 5.8 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 9 }

      raqmonDsSessionDuration OBJECT-TYPE
          SYNTAX     Unsigned32
          UNITS      "seconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Session duration, including setup time.  The SYNTAX of
               this object allows expression of the duration of sessions
               that do not exceed 4660 hours and 20 minutes."
          REFERENCE
              "Section 5.9 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 10 }

      raqmonDsSessionSetupStatus OBJECT-TYPE
          SYNTAX     SnmpAdminString
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Describes appropriate communication session states, e.g.,
               Call Established successfully, RSVP reservation
               failed, etc."
          REFERENCE
              "Section 5.10 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 11 }

      raqmonDsRoundTripEndToEndNetDelay OBJECT-TYPE
          SYNTAX     Unsigned32
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Most recent available information about the
               round-trip end-to-end network delay."
          REFERENCE
              "Section 5.11 of [RFC4710]"
          ::= { raqmonDsNotificationEntry  12}

      raqmonDsOneWayEndToEndNetDelay OBJECT-TYPE
          SYNTAX     Unsigned32
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current



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          DESCRIPTION
              "Most recent available information about the
               one-way end-to-end network delay."
          REFERENCE
              "Section 5.12 of [RFC4710]"
          ::= { raqmonDsNotificationEntry  13}

      raqmonDsApplicationDelay OBJECT-TYPE
          SYNTAX     Unsigned32  (0..65535)
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Most recent available information about the
               application delay."
          REFERENCE
              "Section 5.13 of [RFC4710"
          ::= { raqmonDsNotificationEntry  14}

      raqmonDsInterArrivalJitter OBJECT-TYPE
          SYNTAX     Unsigned32  (0..65535)
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "An estimate of the inter-arrival jitter."
          REFERENCE
              "Section 5.14 of [RFC4710]"
          ::= { raqmonDsNotificationEntry  15}

      raqmonDsIPPacketDelayVariation OBJECT-TYPE
          SYNTAX     Unsigned32  (0..65535)
          UNITS      "milliseconds"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "An estimate of the inter-arrival delay variation."
          REFERENCE
              "Section 5.15 of [RFC4710]"
          ::= { raqmonDsNotificationEntry  16}

      raqmonDsTotalPacketsReceived OBJECT-TYPE
          SYNTAX     Counter32
          UNITS     "packets"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The number of packets transmitted within a communication



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               session by the receiver since the start of the session."
          REFERENCE
              "Section 5.16 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 17 }

      raqmonDsTotalPacketsSent OBJECT-TYPE
          SYNTAX     Counter32
          UNITS     "packets"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The number of packets transmitted within a communication
               session by the sender since the start of the session."
          REFERENCE
              "Section 5.17 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 18 }

      raqmonDsTotalOctetsReceived OBJECT-TYPE
          SYNTAX     Counter32
          UNITS      "octets"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The total number of payload octets (i.e., not including
               header or padding octets) transmitted in packets by the
               receiver within a communication session since the start
               of the session."
          REFERENCE
              "Section 5.18 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 19 }

      raqmonDsTotalOctetsSent OBJECT-TYPE
          SYNTAX     Counter32
          UNITS      "octets"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The number of payload octets (i.e., not including headers
               or padding) transmitted in packets by the sender within
               a communication sub-session since the start of the
               session."
          REFERENCE
              "Section 5.19 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 20 }

      raqmonDsCumulativePacketLoss OBJECT-TYPE
          SYNTAX     Counter32
          UNITS      "packets"



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          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The number of packets from this session whose loss
               had been detected since the start of the session."
          REFERENCE
              "Section 5.20 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 21 }

      raqmonDsPacketLossFraction OBJECT-TYPE
          SYNTAX     Unsigned32 (0..100)
          UNITS      "percentage of packets sent"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The percentage of lost packets with respect to the
               overall packets sent.  This is defined to be 100 times
               the number of packets lost divided by the number of
               packets expected."
          REFERENCE
              "Section 5.21 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 22 }

      raqmonDsCumulativeDiscards OBJECT-TYPE
          SYNTAX     Counter32
          UNITS      "packets"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The number of packet discards detected since the
               start of the session."
          REFERENCE
              "Section 5.22 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 23 }

      raqmonDsDiscardsFraction OBJECT-TYPE
          SYNTAX     Unsigned32 (0..100)
          UNITS      "percentage of packets sent"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The percentage of discards with respect to the overall
               packets sent.  This is defined to be 100 times the number
               of discards divided by the number of packets expected."
          REFERENCE
              "Section 5.23 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 24 }




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      raqmonDsSourcePayloadType OBJECT-TYPE
          SYNTAX     Unsigned32 (0..127)
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The payload type of the packet sent by this RDS."
          REFERENCE
              "RFC 1890, Section 5.24 of [RFC4710] "
          ::= { raqmonDsNotificationEntry 25 }

      raqmonDsReceiverPayloadType OBJECT-TYPE
          SYNTAX     Unsigned32 (0..127)
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "The payload type of the packet received by this RDS."
          REFERENCE
              "RFC 1890, Section 5.25 of [RFC4710] "
      ::= { raqmonDsNotificationEntry 26 }

      raqmonDsSourceLayer2Priority OBJECT-TYPE
          SYNTAX     Unsigned32 (0..7)
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Source Layer 2 priority used by the data source to send
               packets to the receiver by this data source during this
               communication session."
          REFERENCE
              "Section 5.26 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 27 }

      raqmonDsSourceDscp OBJECT-TYPE
          SYNTAX     Dscp
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Layer 3 TOS/DSCP values used by the Data Source to
               prioritize traffic sent."
          REFERENCE
              "Section 5.27 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 28 }

      raqmonDsDestinationLayer2Priority OBJECT-TYPE
          SYNTAX     Unsigned32 (0..7)
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION



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              "Destination Layer 2 priority.  This is the priority used
               by the peer communicating entity to send packets to the
               data source."
          REFERENCE
              "Section 5.28 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 29 }

      raqmonDsDestinationDscp OBJECT-TYPE
          SYNTAX     Dscp
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Layer 3 TOS/DSCP values used by the
               peer communicating entity to prioritize traffic
               sent to the source."
          REFERENCE
              "Section 5.29 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 30 }

      raqmonDsCpuUtilization OBJECT-TYPE
          SYNTAX     Unsigned32 (0..100)
          UNITS      "percent"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Latest available information about the total CPU
               utilization."
          REFERENCE
              "Section 5.30 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 31 }

      raqmonDsMemoryUtilization OBJECT-TYPE
          SYNTAX     Unsigned32 (0..100)
          UNITS      "percent"
          MAX-ACCESS accessible-for-notify
          STATUS     current
          DESCRIPTION
              "Latest available information about the total memory
               utilization."
          REFERENCE
              "Section 5.31 of [RFC4710]"
          ::= { raqmonDsNotificationEntry 32 }

      -- definitions of the notifications
      --
      -- raqmonDsAppName is the only object that MUST be sent by an
      -- RDS every time the static notification is generated.




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      -- raqmonDsTotalPacketsReceived is the only object that MUST be
      -- sent by an RD every time the dynamic notification is generated.

      -- Other objects from the raqmonDsNotificationTable may be
      -- included in the variable binding list.  Specifically, a raqmon
      -- notification will include MIB objects that provide information
      -- about metrics that characterize the application session

         raqmonDsStaticNotification NOTIFICATION-TYPE
          OBJECTS { raqmonDsAppName }
          STATUS current
          DESCRIPTION
              "This notification maps the static parameters in the
               BASIC RAQMON PDU onto an SNMP transport.
               This notification is expected to be sent once per
               session, or when a new sub-session is initiated.
               The following objects MAY be carried by the
               raqmonDsStaticNotification:

               raqmonDsDataSourceDevicePort,
               raqmonDsReceiverDevicePort,
               raqmonDsSessionSetupDateTime,
               raqmonDsSessionSetupDelay,
               raqmonDsSessionDuration,
               raqmonDsSourcePayloadType,
               raqmonDsReceiverPayloadType,
               raqmonDsSourceLayer2Priority,
               raqmonDsSourceDscp,
               raqmonDsDestinationLayer2Priority,
               raqmonDsDestinationDscp

               It is RECOMMENDED to keep the size of a notification
               within the MTU size limits in order to avoid
               fragmentation."
          ::= { raqmonDsNotifications  1 }

      raqmonDsDynamicNotification NOTIFICATION-TYPE
          OBJECTS { raqmonDsTotalPacketsReceived }
          STATUS current
          DESCRIPTION
              "This notification maps the dynamic parameters in the
               BASIC RAQMON PDU onto an SNMP transport.

               The following objects MAY be carried by the
               raqmonDsDynamicNotification:

               raqmonDsRoundTripEndToEndNetDelay,
               raqmonDsOneWayEndToEndNetDelay,



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               raqmonDsApplicationDelay,
               raqmonDsInterArrivalJitter,
               raqmonDsIPPacketDelayVariation,
               raqmonDsTotalPacketsSent,
               raqmonDsTotalOctetsReceived,
               raqmonDsTotalOctetsSent,
               raqmonDsCumulativePacketLoss,
               raqmonDsPacketLossFraction,
               raqmonDsCumulativeDiscards,
               raqmonDsDiscardsFraction,
               raqmonDsCpuUtilization,
               raqmonDsMemoryUtilization

               It is RECOMMENDED to keep the size of a notification
               within the MTU size limits in order to avoid
               fragmentation."

          ::= { raqmonDsNotifications  2 }

      raqmonDsByeNotification NOTIFICATION-TYPE
          OBJECTS { raqmonDsAppName }
          STATUS current
          DESCRIPTION
              "The BYE Notification.  This Notification is the
               equivalent of the RAQMON NULL PDU, which signals the
               end of a RAQMON session."
          ::= { raqmonDsNotifications  3 }

      --
      -- conformance information
      raqmonDsCompliance OBJECT IDENTIFIER ::=
                                           { raqmonDsConformance 1 }
      raqmonDsGroups OBJECT IDENTIFIER ::= { raqmonDsConformance 2 }

   raqmonDsBasicCompliance MODULE-COMPLIANCE
           STATUS current
           DESCRIPTION
              "The compliance statement for SNMP entities that
               implement this MIB module.

               There are a number of INDEX objects that cannot be
               represented in the form of OBJECT clauses in SMIv2, but
               for which we have the following compliance requirements,
               expressed in OBJECT clause form in this description
               clause:

               -- OBJECT      raqmonDsPeerAddrType
               -- SYNTAX      InetAddressType { ipv4(1), ipv6(2) }



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               -- DESCRIPTION
               --     This MIB requires support for only global IPv4
               --     and IPv6 address types.
               --
               -- OBJECT      raqmonDsPeerAddr
               -- SYNTAX      InetAddress (SIZE(4|16))
               -- DESCRIPTION
               --     This MIB requires support for only global IPv4
               --     and IPv6 address types.
               --
              "
           MODULE  -- this module
               MANDATORY-GROUPS { raqmonDsNotificationGroup,
                                  raqmonDsPayloadGroup }
           ::= { raqmonDsCompliance 1 }

      raqmonDsNotificationGroup NOTIFICATION-GROUP
          NOTIFICATIONS { raqmonDsStaticNotification,
                          raqmonDsDynamicNotification,
                          raqmonDsByeNotification }
          STATUS current
          DESCRIPTION
              "Standard RAQMON Data Source Notification group."
          ::= { raqmonDsGroups 1 }

      raqmonDsPayloadGroup OBJECT-GROUP
          OBJECTS { raqmonDsAppName,
                    raqmonDsDataSourceDevicePort,
                    raqmonDsReceiverDevicePort,
                    raqmonDsSessionSetupDateTime,
                    raqmonDsSessionSetupDelay,
                    raqmonDsSessionDuration,
                    raqmonDsSessionSetupStatus,
                    raqmonDsRoundTripEndToEndNetDelay,
                    raqmonDsOneWayEndToEndNetDelay,
                    raqmonDsApplicationDelay,
                    raqmonDsInterArrivalJitter,
                    raqmonDsIPPacketDelayVariation,
                    raqmonDsTotalPacketsReceived,
                    raqmonDsTotalPacketsSent,
                    raqmonDsTotalOctetsReceived,
                    raqmonDsTotalOctetsSent,
                    raqmonDsCumulativePacketLoss,
                    raqmonDsPacketLossFraction,
                    raqmonDsCumulativeDiscards,
                    raqmonDsDiscardsFraction,
                    raqmonDsSourcePayloadType,
                    raqmonDsReceiverPayloadType,



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                    raqmonDsSourceLayer2Priority,
                    raqmonDsSourceDscp,
                    raqmonDsDestinationLayer2Priority,
                    raqmonDsDestinationDscp,
                    raqmonDsCpuUtilization,
                    raqmonDsMemoryUtilization }
          STATUS current
          DESCRIPTION
              "Standard RAQMON Data Source payload MIB objects group."
          ::= { raqmonDsGroups 2 }

      END

3.  IANA Considerations

   Applications using the RAQMON Framework require a single fixed port.
   Port number 7744 is registered with IANA for use as the default port
   for RAQMON PDUs over TCP.  Hosts that run multiple applications may
   use this port as an indication to have used RAQMON or provision a
   separate TCP port as part of provisioning RAQMON RDS and RAQMON
   Collector.

   The particular port number was chosen to lie in the range above 5000
   to accommodate port number allocation practice within the Unix
   operating system, where privileged processes can only use port
   numbers below 1024 and port numbers between 1024 and 5000 are
   automatically assigned by the operating systems.

   The OID assignment for the raqmonDsMIB MODULE-IDENTITY is made
   according to [RFC3737], and there is no need for any IANA action on
   this respect.

4.  Congestion-Safe RAQMON Operation

   As outlined in earlier sections, the TCP congestion control mechanism
   provides inherent congestion safety features when TCP is implemented
   as transport to carry RAQMON PDU.

   To ensure congestion safety, clearly the best thing to do is to use a
   congestion-safe transport protocol such as TCP.  If this is not
   feasible, it may be necessary to fall back to UDP since SNMP over UDP
   is a widely deployed transport protocol.

   When SNMP is chosen as RAQMON PDU Transport, implementers MUST follow
   section 3 of [RFC4710], which outlines measures that MUST be taken to
   use RAQMON in a congestion-safe manner.  Congestion safety





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   requirements in section 3 of [RFC4710] would ensure that a RAQMON
   implementation using SNMP over UDP does not lead to congestion under
   heavy network load.

5.  Acknowledgements

   The authors would like to thank Bill Walker and Joseph Mastroguilio
   from Avaya and Bin Hu from Motorola for their discussions.  The
   authors would also like to extend special thanks to Randy Presuhn,
   who reviewed this document for spelling and formatting purposes, and
   who provided a deep review of the technical content.  We also would
   like to thank Bert Wijnen for the permanent coaching during the
   evolution of this document and the detailed review of its final
   versions.  The Security Considerations section was reviewed by Sam
   Hartman and Kurt D. Zeilenga and almost completely re-written by
   Mahalingam Mani.

6.  Security Considerations

   [RFC4710] outlines a threat model associated with RAQMON and security
   considerations to be taken into account in the RAQMON specification
   to mitigate against those threats.  It is imperative that RAQMON PDU
   implementations be able to provide the following protection
   mechanisms in order to attain end-to-end security:

   1.  Authentication: The RRC SHOULD be able to verify that a RAQMON
       report was originated by the RDS claiming to have sent it.  At
       minimum, an RDS/RRC pair MUST use a digest-based authentication
       procedure to authenticate, like the one defined in [RFC1321].

   2.  Privacy: RAQMON information includes identification of the
       parties participating in a communication session.  RAQMON
       deployments SHOULD be able to provide protection from
       eavesdropping, and to prevent an unauthorized third party from
       gathering potentially sensitive information.  This can be
       achieved by using secure transport protocols supporting
       confidentiality based on encryption technologies such as DES
       (Data Encryption Standard), [3DES], and AES (Advanced Encryption
       Standard) [AES].

   3.  Protection from DoS attacks directed at the RRC: RDSs send RAQMON
       reports as a side effect of external events (for example, receipt
       of a phone call).  An attacker can try to overwhelm the RRC (or
       the network) by initiating a large number of events in order to
       swamp the RRC with excessive numbers of RAQMON PDUs.






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       To prevent DoS attacks against the RRC, the RDS will send the
       first report for a session only after the session has been
       established, so that the session set-up process is not affected.

   4.  NAT and Firewall Friendly Design: The presence of IP addresses
       and TCP/UDP port information in RAQMON PDUs may be NAT-
       unfriendly.  Where NAT-friendliness is a requirement, the RDS MAY
       omit IP address information from the RAQMON PDU.  Another way to
       avoid this problem is by using NAT-Aware Application Layer
       Gateways (ALGs) to ensure that correct IP addresses appear in
       RAQMON PDUs.

   For the usage of TCP, TLS MUST be used to provide transport layer
   security.  Section 6.1 describes the usage of TLS with RAQMON.

   This memo also defines the RAQMON-RDS-MIB module with the purpose of
   mapping the RAQMON PDUs into SNMP Notifications.  To attain end-to-
   end security, the following measures have been taken in the RAQMON-
   RDS-MIB module design:

   There are no management objects defined in this MIB module that have
   a MAX-ACCESS clause of read-write and/or read-create.  Consequently,
   if this MIB module is implemented correctly, there is no risk that an
   intruder can alter or create any management objects of this MIB
   module via direct SNMP SET operations.

   Some of the readable objects in this MIB module (i.e., objects with a
   MAX-ACCESS other than not-accessible) may be considered sensitive or
   vulnerable in some network environments.  It is thus important to
   control even GET and/or NOTIFY access to these objects and possibly
   to even encrypt the values of these objects when sending them over
   the network via SNMP.  These are the tables and objects and their
   sensitivity/vulnerability:

   raqmonDsNotificationTable

   The objects in this table contain user session information, and their
   disclosure may be sensitive in some environments.

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPsec),
   even then, there is no control as to who on the secure network is
   allowed to access and GET/SET (read/change/create/delete) the objects
   in this MIB module.







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   It is RECOMMENDED that implementers consider the security features as
   provided by the SNMPv3 framework (see [RFC3410], section 8),
   including full support for the SNMPv3 cryptographic mechanisms (for
   authentication and confidentiality).

   It is a customer/operator responsibility to ensure that the SNMP
   entity giving access to an instance of this MIB module is properly
   configured to give access to the objects only to those principals
   (users) that have legitimate rights to indeed GET or SET
   (change/create/delete) them.

6.1.  Usage of TLS with RAQMON

6.1.1.  Confidentiality & Message Integrity

   The subsequently authorized RAQMON data flow itself is protected by
   the same TLS security association that protects the client-side
   exchange.  This standard TLS channel is now bound to the server
   through the above client-side authentication.  The session itself is
   identified by the tuple {RDS ip-address:RDS_port / RRC ip-address:
   RRC port}.

6.1.2.  TLS CipherSuites

   Several issues should be considered when selecting TLS ciphersuites
   that are appropriate for use in a given circumstance.  These issues
   include the following:

   The ciphersuite's ability to provide adequate confidentiality
   protection for passwords and other data sent over the transport
   connection.  Client and server implementers should recognize that
   some TLS ciphersuites provide no confidentiality protection, while
   other ciphersuites that do provide confidentiality protection may be
   vulnerable to being cracked using brute force methods, especially in
   light of ever-increasing CPU speeds that reduce the time needed to
   successfully mount such attacks.

   Client and server implementers should carefully consider the value of
   the password or data being protected versus the level of
   confidentiality protection provided by the ciphersuite to ensure that
   the level of protection afforded by the ciphersuite is appropriate.

   The ciphersuite's vulnerability (or lack thereof) to man-in-the-
   middle attacks.  Ciphersuites vulnerable to man-in-the-middle attacks
   SHOULD NOT be used to protect passwords or sensitive data, unless the
   network configuration is such that the danger of a man-in-the-middle
   attack is negligible.




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   After a TLS negotiation (either initial or subsequent) is completed,
   both protocol peers should independently verify that the security
   services provided by the negotiated ciphersuite are adequate for the
   intended use of the RAQMON session.  If not, the TLS layer should be
   closed.

   Spoofing Attacks: When anonymous TLS alone is negotiated without
   client authentication, the client's identity is never established.
   This easily allows any end-entity to establish a TLS-secured RAQMON
   connection to the RRC.  This not only offers an opportunity to spoof
   legitimate RDS clients and hence compromise the integrity of RRC
   monitoring data, but also opens the RRC up to unauthorized clients
   posing as genuine RDS entities to launch a DoS by flooding data.
   RAQMON deployment policy MUST consider requiring RDS client
   authentication during TLS session establishment, especially when RDS
   clients communicate across unprotected internet.

   Insider attacks: Even client-authenticated TLS connections are open
   to spoofing attacks by one trusted client on another.  Validation of
   RDS source address against RDS TLS-session source address SHOULD be
   performed to detect such attempts.

6.1.3.  RAQMON Authorization State

   Every RAQMON session (between RDS and RRC) has an associated
   authorization state.  This state is comprised of numerous factors
   such as what (if any) authorization state has been established, how
   it was established, and what security services are in place.  Some
   factors may be determined and/or affected by protocol events (e.g.,
   StartTLS, or TLS closure), and some factors may be determined by
   external events (e.g., time of day or server load).

   While it is often convenient to view authorization state in
   simplistic terms (as we often do in this technical specification)
   such as "an anonymous state", it is noted that authorization systems
   in RAQMON implementations commonly involve many factors that
   interrelate.

   Authorization in RAQMON is a local matter.  One of the key factors in
   making authorization decisions is authorization identity.  The
   initial session establishment defined in Section 2.2 allows
   information to be exchanged between the client and server to
   establish an authorization identity for the RAQMON session.  The RRC
   is not to allow any RDS-transactions-related traffic through for
   processing until the client authentication is complete, unless
   anonymous authentication mode is negotiated.





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   Upon initial establishment of the RAQMON session, the session has an
   anonymous authorization identity.  Among other things, this implies
   that the client need not send a TLSStartRequired in the first PDU of
   the RAQMON message.  The client may send any operation request prior
   to binding RDS to any authentication, and the RRC MUST treat it as if
   it had been performed after an anonymous RAQMON session start.

   The RDS automatically is placed in an unauthorized state upon RRC
   sending a TLSstart request to the RRC.

   It is noted that other events both internal and external to RAQMON
   may result in the authentication and authorization states being moved
   to an anonymous one.  For instance, the establishment, change, or
   closure of data security services may result in a move to an
   anonymous state, or the user's credential information (e.g.,
   certificate) may have expired.  The former is an example of an event
   internal to RAQMON, whereas the latter is an example of an event
   external to RAQMON.

7.  References

7.1.  Normative References

   [RFC2119]     Bradner, S., "Key words for use in RFCs to Indicate
                 Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2578]     McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
                 J., Rose, M., and S. Waldbusser, "Structure of
                 Management Information Version 2 (SMIv2)", STD 58,
                 RFC 2578, April 1999.

   [RFC2579]     McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
                 J., Rose, M., and S. Waldbusser, "Textual Conventions
                 for SMIv2", STD 58, RFC 2579, April 1999.

   [RFC2580]     McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
                 J., Rose, M., and S. Waldbusser, "Conformance
                 Statements for SMIv2", STD 58, RFC 2580, April 1999.

   [RFC2819]     Waldbusser, S., "Remote Network Monitoring Management
                 Information Base", STD 59, RFC 2819, May 2000.

   [RFC3289]     Baker, F., Chan, K., and A. Smith, "Management
                 Information Base for the Differentiated Services
                 Architecture", RFC 3289, May 2002.






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   [RFC3411]     Harrington, D., Preshun, R., and B. Wijnen, "An
                 Architecture for Describing Simple Network Management
                 Protocol (SNMP) Management Frameworks", STD 62,
                 RFC 3411, December 2002.

   [RFC4001]     Daniele, M., Haberman, B., Routhier, S., and J.
                 Schoenwalder, "Textual Conventions for Internet Network
                 Addresses", RFC 4001, February 2005.

   [RFC791]      Postel, J., "Internet Protocol", STD 5, RFC 791,
                 September 1981.

   [RFC793]      Postel, J., "Transmission Control Protocol", STD 7,
                 RFC 793, September 1981.

   [RFC4710]     Siddiqui, A., Romascanu, D., and E. Golovinsky, "Real-
                 time Application Quality-of-Service Monitoring
                 (RAQMON)", RFC 4710, October 2006.

   [TLS]         Dierks, T. and E. Rescorla, "The Transport Layer
                 Security (TLS) Protocol Version 1.1", RFC 4346, April
                 2006.

7.2.  Informative References

   [3DES]        Americation National Standards Institute, "Triple Data
                 Encryption Algorithm Modes of Operation", ANSI
                 X9.52-1998.

   [AES]         Federal Information Processing Standard (FIPS),
                 "Specifications for the ADVANCED ENCRYPTION
                 STANDARD(AES)", Publication 197, November 2001.

   [IEEE802.1D]  "Information technology-Telecommunications and
                 information exchange between systems--Local and
                 metropolitan area networks-Common Specification
                 a--Media access control (MAC) bridges:15802-3:
                 1998(ISO/IEC)", [ANSI/IEEE Std 802.1D Edition], 1998.

   [RFC1305]     Mills, D., "Network Time Protocol Version 3", RFC 1305,
                 March 1992.

   [RFC1321]     Rivest, R., "Message Digest Algorithm MD5", RFC 1321,
                 April 1992.







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   [RFC3410]     Case, J., Mundy, R., Partain, D., and B. Stewart,
                 "Introduction and Applicability Statements for
                 Internet-Standard Management Framework", RFC 3410,
                 December 2002.

   [RFC3414]     Blumenthal, U. and B. Wijnen, "User-based Security
                 Model (USM) for version 3 of the Simple Network
                 Management Protocol (SNMPv3)", RFC 3414, December 2002.

   [RFC3550]     Schulzrinne, H., Casner, S., Frederick, R., and V.
                 Jacobson, "RTP: A Transport Protocol for Real-Time
                 Applications", RFC 3550, July 2003.

   [RFC3551]     Schulzrinne, H. and S. Casner, "RTP Profile for Audio
                 and Video Conferences with Minimal Control", STD 65,
                 RFC 3551, July 2003.

   [RFC3629]     Yergeau, F., "UTF-8, a transformation format of ISO
                 10646", STD 63, RFC 3629, November 2003.

   [RFC3737]     Wijnen, B. and A. Bierman, "IANA Guidelines for the
                 Registry of Remote Monitoring (RMON) MIB modules",
                 RFC 3737, April 2004.

   [RFC4513]     Harrison, R., "Lightweight Directory Access Protocol
                 (LDAP): Authentication Methods and Security
                 Mechanisms", RFC 4513, June 2006.

   [TLS-PSK]     Eronen, P. and H. Tschofenig, "Pre-Shared Key
                 Ciphersuites for Transport Layer Security (TLS)",
                 RFC 4279, December 2005.




















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Appendix A.  Pseudocode

   The implementation notes included in Appendix are for informational
   purposes only and are meant to clarify the RAQMON specification.

   Pseudocode for RDS & RRC

   We provide examples of pseudocode for aspects of RDS and RRC.  There
   may be other implementation methods that are faster in particular
   operating environments or have other advantages.

     RDS:
             when (session starts} {
               report.identifier = session.endpoints, session.starttime;
               report.timestamp = 0;
               while (session in progress) {
                 wait interval;
                 report.statistics = update statistics;
                 report.curtimestamp += interval;
                 if encryption required
                    report_data = encrypt(report, encrypt parameters);
                 else
                    report_data = report;
                    raqmon_pdu = header, report_data;
                 send raqmon-pdu;
               }
             }


     RRC:
             listen on raqmon port
             when ( raqmon_pdu received ) {
                 decrypt raqmon_pdu.data if needed

                 if report.identifier in database
                    if report.current_time_stamp > last update
                       update session statistics from report.statistics
                    else
                       discard report
              }











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Authors' Addresses

   Anwar Siddiqui
   Avaya
   307 Middletown Lincroft Road
   Lincroft, NJ  80302
   USA

   Phone: +1 732 852-3200
   EMail: anwars@avaya.com


   Dan Romascanu
   Avaya
   Atidim Technology Park, Bldg #3
   Tel Aviv,   61131
   Israel

   Phone: +972-3-645-8414
   EMail: dromasca@avaya.com


   Eugene Golovinsky
   Alert Logic

   Phone: +1 713 918-1816
   EMail: gene@alertlogic.net


   Mahfuzur Rahman
   Samsung Information Systems America
   75 West Plumeria Drive
   San Jose, CA  95134
   USA

   Phone: +1 408 544-5559


   Yongbum Yong Kim
   Broadcom
   3151 Zanker Road
   San Jose, CA  95134
   USA

   Phone: +1 408 501-7800
   EMail: ybkim@broadcom.com





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Full Copyright Statement

   Copyright (C) The Internet Society (2006).

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