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Versions: 00 01 02 03 04 05 06 07 08 09 10 RFC 6003

Network Working Group                                   D. Papadimitriou
Internet Draft                                            Alcatel-Lucent
Category: Standards Track
Created: July 12, 2008
Expires: January 11, 2009

                        Ethernet Traffic Parameters

            draft-ietf-ccamp-ethernet-traffic-parameters-05.txt

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Copyright Notice

   Copyright (C) The IETF Trust (2008).

Abstract

   This document describes the Metro Ethernet Forum (MEF) - specific
   Ethernet Traffic Parameters as described in MEF10.1 when using
   Generalized Multi-Protocol Label Switching (GMPLS) Resource
   ReSerVation Protocol - Traffic Engineering (RSVP-TE) signaling.




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Conventions Used In This Document

   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 RFC-2119 [RFC2119].

   Moreover, the reader is assumed to be familiar with the terminology
   [MEF10.1] as well as [RFC3471] and [RFC3473].

1. Introduction

   Per [RFC3471], GMPLS allows the inclusion of technology specific
   parameters in signaling. Ethernet SENDER_TSPEC and FLOWSPEC specific
   objects are introduced in this document that describe Metro Ethernet
   Forum (MEF) Ethernet traffic parameters as specified in [MEF10.1].

   These traffic parameters MUST be used when L2SC is specified in the
   LSP Switching Type field of a Generalized Label Request (see
   [RFC3471]) and the LSP encoding type is Ethernet.

   For Ethernet Private Line (EPL) services [MEF6], these traffic
   parameters are applicable non-discriminately to all EVCs crossing a
   given port.

   For Ethernet Virtual Private Line (EVPL) services [MEF6], these
   traffic parameters are applicable per Ethernet Virtual Connection
   (EVC) with single or multiple Class of Service (CoS), independent
   of its associated (set of) VLAN ID (VID).

   Association between EVC and VIDs is detailed in [MEF10.1]. The format
   and encoding of the (set of) VIDs is documented in a companion
   document [GMPLS-ESVCS].

2. Overview

   The Ethernet SENDER_TSPEC/FLOWSPEC object includes the Ethernet link
   type (switching granularity) of the requested LSP, and the MTU value
   for the LSP.

   The Bandwidth Profile defines the set of traffic parameters
   applicable to a sequence of Service Frames, referred to as bandwidth
   profile parameters:

   - Committed Rate: Indicates the rate at which traffic commits to
     be sent to the Ethernet LSP. The Committed Rate is described in
     terms of the CIR (Committed Information Rate) and CBS (Committed
     Burst Size) traffic parameters.



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     CIR is defined as the average rate (in bytes per unit of time)
     up to which the network is committed to transfer frames and
     meets its performance objectives.

     CBS defines a limit on the maximum number of information units
     (e.g., bytes) available for a burst of frames sent at the
     interface speed to remain CIR-conformant.

   - Excess Rate: Indicates the extent by which the traffic sent on an
     Ethernet LSP exceeds the committed rate. The Excess Rate is
     described in terms of the EIR (Excess Information Rate) and EBS
     (Excess Burst Size) traffic parameters.

     EIR is defined as the average rate (in bytes per unit of time),
     in excess of the CIR, up to which the network may transfer
     frames without any performance objectives.

     EBS defines a limit on the maximum number of information units
     (e.g., bytes) available for a burst of frames sent at the
     interface speed to remain EIR-conformant.

   - The color mode (CM) parameter indicates whether the "color-
     aware" or "color-blind" property is employed by the bandwidth
     profile.

   - The coupling flag (CF) parameter allows the choice between two
     modes of operations of the rate enforcement algorithm.

3. Ethernet SENDER_TSPEC Object

   The Ethernet SENDER_TSPEC object (Class-Num = 12, Class-Type = TBA by
   IANA recommended value 6) has the following format:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            Length             | Class-Num (12)|   C-Type (6)  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Switching Granularity     |              MTU              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                              TLVs                             ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+






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   Switching Granularity (SG): 16 bits

      This field indicates the type of link that comprises the
      requested Ethernet LSP.

      The permitted Ethernet Link Type values are:

        Value   Switching Granularity
        -----   ---------------------
          0       Provided in signaling. See [GMPLS-ESVCS]
          1       Ethernet Port (for port-based service)
          2       Ethernet Frame (for EVC-based service)

      Values 0 through 127 are assigned by IANA via IETF Standards
      Track RFC action.

      Values 128 through 255 are reserved for vendor specific usage.

   MTU: 16 bits

      This is a two-octet value indicating the MTU in octets.

      The MTU MUST NOT take a value smaller than 46 bytes for Ethernet
      v2 and 38 bytes for IEEE 802.3.

   TLV:

      The Ethernet SENDER_TSPEC object MUST include at least one TLV
      and MAY include more than one TLV.

      Each TLV has the following format:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      ~                             Value                             ~
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+









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         Type: 16 bits

            Defined values are:

            Type     Length   Format            Description
            --------------------------------------------------
            1        TBD      Reserved          Reserved
            2        24       see Section 3.1   Ethernet Bandwidth
                                                Profile [MEF10.1]
            3        8        [GMPLS-ESVCS]     Layer 2 Control
                                                Processing (L2CP)

            Values 0 and 255 are reserved.

            Values 1 through 239 are assigned by IANA via IETF Standards
            Track RFC Action.

            Values 240 through 254 are reserved for vendor specific
            usage.

         Length: 16 bits

            Indicates the length in bytes of the whole TLV including the
            Type and Length fields. A value field whose length is not a
            multiple of four MUST be zero-padded (with trailing zeros)
            so that the TLV is four-octet aligned.

3.1 Ethernet Bandwidth Profile TLV

   The Type 2 TLV indicates the Ethernet Bandwidth Profile. It defines
   an upper bound on the volume of the expected service frames belonging
   to a particular Ethernet service instance. The Ethernet SENDER_TSPEC
   object MAY include more than one Ethernet Bandwidth Profile TLV.

   The Type 2 TLV has the following format:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Profile    |     Index     |            Reserved           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             CIR                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             CBS                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             EIR                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             EBS                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


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   Profile: 8 bits (this field is to be registered by IANA)

      This field is defined as a vector of binary flags. The following
      flags are defined:

         Flag 1 (bit 0): coupling flag (CF)
         Flag 2 (bit 1): color mode (CM)

      Where bit 0 is the low order bit. Other flags are reserved,
      they SHOULD be set to zero when sent, and SHOULD be ignored when
      received.

      A flag is set to one to indicate that the corresponding metering
      is requested.

      The Flag 1 allows the choice between two modes of operations of
      the rate enforcement algorithm.

      The Flag 2 indicates whether the color-aware or color-blind
      property is employed by the bandwidth profile. When Flag 2 is set
      to 0 (1), the bandwidth profile algorithm is said to be in
      color blind (color aware) mode.

   Index: 8 bits

      The index field is used to reference bandwidth allocated for a
      given traffic class in case a multiple-class LSP is being
      requested. The index field value MUST correspond to at least one
      of the index value included in the extended ClassType object ([DS-
      TE], [MCOS]).

      A given index value j can be associated to at most N Class-Type
      values CTi (i =< N) of the extended Class-Type object. This
      applies in case a set of one or more CTi maps a single BW profile
      (shared). An example of value setting consists then in assigning
      an arbitrary value (between 0x10 and 0x77) associated to set of
      CTi.

      As a particular case, a given index value j can be associated to a
      single CTi (1:1 correspondence). An example of index value setting
      consists then in allocating the CTi value to the index field
      itself (i.e. 0x00,...,0x07). This applies in case a single CTi
      maps a single BW profile or multiple BW profiles (dedicated). In
      the former case (single BW profile), the Ethernet SENDER_TSPEC
      object includes a single Ethernet Bandwidth Profile TLV. In the
      second case, the Ethernet SENDER_TSPEC includes a set of more than
      one Ethernet Bandwidth Profile TLVs (whose respective index value
      is associated to a single CTi value).


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      Note that the current specification allow for combining shared and
      dedicated BW profiles to the same LSP. That is, an Ethernet
      SENDER_TSPEC MAY include multiple Ethernet Bandwidth Profile TLVs
      whose respective index can be associated on a 1:1 basis to a
      single CTi or to a set of multiple CTi.

      For each subobject of the extended Class-Type object [MCOS]:
      - each CTi value SHOULD correspond 1:1 to MEF CE VLAN-CoS
      - the BW requested per CTi field MAY be used for bandwidth
        accounting purposes.

      By default, the value of the index field MUST be set to 0.

   Reserved: 16 bits

      These bits SHOULD be set to zero when sent and MUST be ignored
      when received.

   CIR (Committed Information Rate): 32 bits

      The value of the CIR is in units of bytes per second. The CIR is
      encoded as a 32-bit IEEE single-precision floating-point number
      (see [RFC4506]).

      The CIR value MUST be greater than or equal to 0.

   CBS (Committed Burst Size): 32 bits

      The value of the CBS is in units of bytes. The CBS is encoded
      as a 32-bit IEEE single-precision floating-point number (see
      [RFC4506]).

      When CIR is strictly greater than 0 (CIR > 0), the CBS MUST be
      greater than or equal to the maximum frame size.

   EIR (Excess Information Rate): 32 bits

      The value of the EIR is in units of bytes per second. The EIR
      is encoded as a 32-bit IEEE single-precision floating-point
      number (see [RFC4506]).

      The EIR value MUST be greater than or equal to 0.

   EBS (Excess Burst Size): 32 bits

      The value of the EBS is in units of bytes. The EBS is encoded
      as a 32-bit IEEE single-precision floating-point number (see
      [RFC4506]).


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      When EIR is strictly greater than 0 (EIR > 0), the EBS MUST be
      greater than or equal to the maximum frame size.

4. Ethernet FLOWSPEC Format

   The Ethernet FLOWSPEC object (Class-Num = 12, Class-Type = TBA by
   IANA - recommended value 6) has the same format as the Ethernet
   SENDER_TSPEC object.

5. ADSPEC Considerations

   There is no ADSPEC associated with the Ethernet SENDER_TSPEC object.

   Either the ADSPEC is omitted or an Int-serv ADSPEC with the Default
   General Characterization Parameters and Guaranteed Service fragment
   is used, see [RFC2210].

6. Processing

   The Ethernet SENDER_TSPEC object carries the traffic specification
   generated by the RSVP session sender. The Ethernet SENDER_TSPEC
   object SHOULD be forwarded and delivered unchanged to both
   intermediate and egress nodes.

   The Ethernet FLOWSPEC object carries reservation request information
   generated by receivers. As with any FLOWSPEC object, Ethernet
   FLOWSPEC object flows upstream toward the ingress node.

   Intermediate and egress nodes MUST verify that the node itself and
   the interfaces on which the LSP will be established can support the
   requested Switching Granularity, MTU and values included in sub-
   object TLVs. If the requested value(s) can not be supported, the
   receiver node MUST generate a PathErr message with the error code
   "Traffic Control Error" and the error value "Service unsupported"
   (see [RFC2205]).

   In addition, if the MTU field is received with a value smaller than
   the minimum transfer unit size of the Ethernet frame (e.g. 46 bytes
   for Ethernet v2, 38 bytes for IEEE 802.3), the node MUST generate a
   PathErr message with the error code "Traffic Control Error" and the
   error value "Bad Tspec value" (see [RFC2205]).

   Error processing of the Extended Class-Type object follows rules
   defined in [MCOS]. Moreover, an LSR receiving a Path message with the
   Extended Class-Type object, which recognizes the object and the
   particular Class-Type but does detect a mismatch in the index values,
   MUST send a PathErr towards the sender with the error code "Extended
   Class-Type Error" and the error value "Class-Type mismatch" (see
   [RFC2205]).

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7. Security Considerations

   This document introduces no new security considerations to either
   [RFC3473].

   GMPLS security is described in section 11 of [RFC3471] and refers to
   [RFC3209] for RSVP-TE. Further details of MPLS-TE and GMPLS security
   can be found in [MPLS-SEC].

8. IANA Considerations

   IANA maintain registries and sub-registries for RSVP-TE as used by
   GMPLS. IANA is requested to make allocations from these registries as
   set out in the following scetions.

8.1. RSVP Objects Class Types

   This document introduces two new Class Types for existing RSVP
   objects. IANA is requested to make allocations from the "Resource
   ReSerVation Protocol (RSVP) Parameters" registry using the "Class
   Names, Class Numbers, and Class Types" sub-registry.

   Class
   Number  Class Name                            Reference
   ------  -----------------------               ---------
        9  FLOWSPEC                              [RFC2205]

           Class Types or C-Types:

             6   Ethernet SENDER_TSPEC           [This.I-D]

       12  SENDER_TSPEC                          [RFC2205]

           Class Types or C-Types:

             6   Ethernet SENDER_TSPEC           [This.I-D]

8.2. Ethernet Switching Granularities

   IANA maintains a registry of GMPLS parameters called "Generalized
   Multi-Protocol Label Switching (GMPLS) Signaling Parameters". IANA is
   requested to create a new sub-registry called "Ethernet Switching
   Granularities" to contain the values that may be carried in the
   Switching Granularity field of the Ethernet SENDER_TSPEC object.

   Values may be assigned as follows:
     0     Reserved
     1-127 IETF Standards Track RFC action
   128-255 Vendor Specific Usage

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   Initial entries in this sub-registry are as follows:

   Value   Switching Granularity                      Reference
   -----   --------------------------------------     ---------
     0     Reserved                                   [This.I-D]
     1     Ethernet Port (for port-based service)     [This.I-D]
     2     Ethernet Frame (for EVC-based service)     [This.I-D]

8.3. Ethernet Sender TSpec TLVs

   IANA maintains a registry of GMPLS parameters called "Generalized
   Multi-Protocol Label Switching (GMPLS) Signaling Parameters". IANA is
   requested to create a new sub-registry called "Ethernet Sender TSpec
   TLVs" to contain the TLV type values for TLVs carried in the Ethernet
   SENDER_TSPEC object.

   Values may be assigned as follows:
     0     Reserved
     1-239 IETF Standards Track RFC action
   240-254 Vendor Specific Usage
   255     Reserved

   Initial entries in this sub-registry are as follows:

   Type     Description                        Reference
   -----    --------------------------------   ---------
     0      Reserved                           [This.I-D]
     1      Reserved                           [This.I-D]
     2      Ethernet Bandwidth Profile         [This.I-D]
     3      Layer 2 Control Processing (L2CP)  [This.I-D]
   255      Reserved                           [This.I-D]

8.4. Ethernet Bandwidth Profiles

   IANA maintains a registry of GMPLS parameters called "Generalized
   Multi-Protocol Label Switching (GMPLS) Signaling Parameters". IANA is
   requested to create a new sub-registry called "Ethernet Bandwidth
   Profiles" to contain bit flags carried in the Ethernet Bandwidth
   Profile TLV of the Ethernet SENDER_TSPEC object.

   Bits are to be allocated by IETF Standards Track RFC action.
   Bits are numbered from bit 0 as the low order bit.

   Bit   Hex   Description                   Reference
   ---   ----  --------------------------    -------------
     0   0x01  Coupling flag (CF)            [This.I-D]
     1   0x02  Color mode (CM)               [This.I-D]



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9. References

9.1.  Normative References

   [GMPLS-ESVCS]  Berger, L., et al., "Generalized MPLS (GMPLS) Support
                  For Metro Ethernet Forum and G.8011 Ethernet
                  Services", draft-berger-ccamp-gmpls-ether-svcs, work
                  in progress.

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

   [RFC2205]      Braden, R., Zhang, L., Berson, S., Herzog, S., and S.
                  Jamin, "Resource ReSerVation Protocol (RSVP) --
                  Version 1 Functional Specification", RFC 2205,
                  September 1997.

   [RFC2210]      Wroclawski, J., "The Use of RSVP with IETF Integrated
                  Services", RFC 2210, September 1997.

   [RFC3209]      Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan,
                  V., and G. Swallow, "RSVP-TE: Extensions to RSVP for
                  LSP Tunnels", RFC 3209, December 2001.

   [RFC3471]      Berger, L., "Generalized Multi-Protocol Label
                  Switching (GMPLS) Signaling Functional Description",
                  RFC 3471, January 2003.

   [RFC3473]      Berger, L., "Generalized Multi-Protocol Label
                  Switching (GMPLS) Signaling Resource ReserVation
                  Protocol-Traffic Engineering (RSVP-TE) Extensions",
                  RFC 3473, January 2003.

   [RFC4506]      Eisler, M., Ed. "XDR: External Data Representation
                  Standard", RFC 4506, STD 67, May 2006.


9.2.  Informative References

   [MEF10.1]      The MEF Technical Specification, "Ethernet Services
                  Attributes Phase 2", MEF 10.1, November 2006.

   [MEF6]         The Metro Ethernet Forum, "Ethernet Services
                  Definitions - Phase I", MEF 6, June 2004.

   [MEF11]        The Metro Ethernet Forum , "User Network
                  Interface (UNI) Requirements and Framework",
                  MEF 11, November 2004.


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   [MCOS]         I.Minei et al., "Extensions for Differentiated
                  Services-aware Traffic Engineered LSPs", draft-minei-
                  diffserv-te-multi-class, work in progress.

   [MPLS-SEC]     Fang, L., " Security Framework for MPLS and GMPLS
                  Networks", draft-ietf-mpls-mpls-and-gmpls-security-
                  framework, work in progress.

10. Acknowledgments

   Many thanks to Adrian Farrel for his comments. Lou Berger provided
   the input on control traffic processing.

11. Author's Addresses

   Dimitri Papadimitriou
   Alcatel-Lucent Bell
   Copernicuslaan 50
   B-2018 Antwerpen, Belgium

   Phone: +32 3 2408491
   E-mail: dimitri.papadimitriou@alcatel-lucent.be


Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.











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