Network Working Group                                  D.                             Dimitri Papadimitriou
     Internet Draft                                           Alcatel-Lucent
     Intended status: Standards Track                       October 31, 2008
     Expires:                          April 30, 7, 2009
     Expires: October 6, 2009

                           Ethernet Traffic Parameters

                 draft-ietf-ccamp-ethernet-traffic-parameters-06.txt

                 draft-ietf-ccamp-ethernet-traffic-parameters-07.txt

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     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.

     1. Introduction

        Per [RFC3471], GMPLS Generalized Multi-Protocol Label Switching (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 the L2SC value is
        specified in the LSP Switching Type field of a Generalized Label
        Request (see [RFC3471]) and the LSP encoding type is Ethernet. For
        example:

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

        o 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].

        This does not prevent broader usage for Ethernet LSP of the traffic
        parameters specified in this document.

     2. 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].

     3. 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:

       o 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.

         o

         . 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.

         o

         . 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.

       o 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.

         o

         . 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.

         o

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

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

       o Coupling flag (CF): allows the choice between two modes of
         operations of the rate enforcement algorithm.

     4. Ethernet SENDER_TSPEC Object

        The Ethernet SENDER_TSPEC object (Class-Num = 12, Class-Type = TBA by
        IANA, with 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                             ~
           |                                                               |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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

        TLV (Type-Length-Value):

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

           Each TLV MUST have 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                             ~
           |                                                               |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

           Type: 16 bits

              Defined values are:

              Type     Length   Format            Description
              ------------------------------------------------------
              1        TBD      Reserved          Reserved value
              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.

     4.1. Ethernet Bandwidth Profile TLV

        The Type 2 TLV specifies 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                               |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        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 value 1 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 value 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 values included in the extended ClassType CLASSTYPE object [RFC4124] or
           EXTENDED_CLASSTYPE object ([DS-
           TE], [MCOS]). [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 (shared) BW
           profile. An example of value setting consists then in assigning
           an arbitrary value (comprised comprised within the range [0x08,0xF8],
           defined by the 5 MSB of the Index field) [0x08,0xF8[
           associated to a set of
           CTi. CTi, the values in the range [0xF8,0xFF]
           being selected for reserved sets. This allows mapping to one of
           248 pre-defined CTi sets.

           A given index value j can be associated to a single CTi (1:1
           correspondence). In this case, the index value setting consists
           then in assigning the 3 LSB of the index field itself to the CTi
           value itself (comprised in the range [0x00,0x07]). This applies in
           case a single CTi maps a single (dedicated) BW profile or multiple
           (dedicated) BW profiles. 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).

           Note that the current specification allow for combining shared and
           dedicated BW profiles to the same LSP. That is, an Ethernet
           SENDER_TSPEC object 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]:
           o Each CTi value SHOULD correspond 1:1 to MEF CE VLAN-CoS
           o 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]).

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

     5. Ethernet FLOWSPEC Object

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

     6. Ethernet ADSPEC Object

        There is no ADSPEC object associated with the Ethernet SENDER_TSPEC
        object.

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

     7. 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 message towards the sender with the error code
        "Extended Class-Type Error" and the error value "Class-Type mismatch"
        (see [RFC2205]).

     8. 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].

     9. 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 sections.

     9.1. 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 Type (C-Type):

                      6   Ethernet SENDER_TSPEC             [This.I-D]

        Class Number  Class Name                            Reference
        ------------   ----------  -----------------------               ---------
        12            SENDER_TSPEC                          [RFC2205]

                      Class Type (C-Type):

                      6   Ethernet SENDER_TSPEC             [This.I-D]

     9.2. 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 shall be assigned as follows:

        000          Reserved
        001-127      IETF Standards Track RFC action
        128-255      Vendor Specific Usage

        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]

     9.3. 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 shall be assigned as follows:

        000          Reserved
        001-239      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]

     9.4. 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]

     10. Acknowledgments

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

     11. References

     11.1. 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.

        [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.

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

        [RFC4124]   Le Faucheur et al, "Protocol extensions for support of
                    Diff-Serv-aware MPLS Traffic Engineering", RFC4124.

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

     11.2. 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.

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

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

     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
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