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RFC 5603 - Ethernet Pseudowire (PW) Management Information Base


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Network Working Group                                      D. Zelig, Ed.
Request for Comments: 5603                                        Oversi
Category: Standards Track                                 T. Nadeau, Ed.
                                                                      BT
                                                               July 2009

       Ethernet Pseudowire (PW) Management Information Base (MIB)

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes managed objects for modeling of Ethernet
   pseudowire (PW) services.

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) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents in effect on the date of
   publication of this document (http://trustee.ietf.org/license-info).
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1. Introduction ....................................................2
   2. The Internet-Standard Management Framework ......................2
   3. Conventions .....................................................3
   4. Overview ........................................................3
   5. Feature Checklist ...............................................4
   6. PW ENET MIB Module Usage ........................................4
   7. PW-ENET Management Model ........................................5
   8. Example of the PW-ENET MIB Module Usage .........................6
   9. Service-Delimiting Modes ........................................6
   10. Object Definitions .............................................9
   11. Security Considerations .......................................19
   12. IANA Considerations ...........................................21
   13. References ....................................................21
      13.1. Normative References .....................................21
      13.2. Informative References ...................................22
   14. Acknowledgments ...............................................22

1. Introduction

   This document describes a model for managing Ethernet pseudowire
   services for transmission over a Packet Switched Network (PSN).  This
   MIB module is generic and common to all types of PSNs supported in
   the Pseudowire Emulation Edge-to-Edge (PWE3) architecture [RFC3985],
   which describes the transport and encapsulation of L1 and L2 services
   over supported PSN types.

   In particular, the MIB module associates a port or specific VLANs on
   top of a physical Ethernet port or a virtual Ethernet interface (for
   Virtual Private LAN Service (VPLS)) to a point-to-point PW.  It is
   complementary to the PW-STD-MIB [RFC5601], which manages the generic
   PW parameters common to all services, including all supported PSN
   types.

2.  The Internet-Standard Management Framework

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   RFC 3410 [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through 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, RFC
   2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
   [RFC2580].

3.  Conventions

   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 [BCP14].

   This document adopts the definitions, acronyms, and mechanisms
   described in [RFC3985] and [RFC3916].  Unless otherwise stated, the
   mechanisms of [RFC3985] apply and will not be re-described here.

4.  Overview

   The MIB module structure for defining a PW service is composed of
   three layers of MIB modules functioning together.  This general model
   is defined in the PWE3 architecture [RFC3985].  The layering model is
   intended to sufficiently isolate PW services from the underlying PSN
   layer that carries the emulated service.  This is done at the same
   time as providing a standard means for connecting any supported
   services to any supported PSNs.

   The first layer, known as the service layer, contains service-
   specific modules.  These modules define service-specific management
   objects that interface or collaborate with existing MIB modules for
   the native version of the service.  The service-specific module
   "glues" the standard modules to the PWE3 MIB modules.

   The next layer of the PWE3 MIB framework is the PW MIB module
   [RFC5601].  This module is used to configure general parameters of
   PWs that are common to all types of emulated services and PSNs.  This
   layer is connected to the service-specific layer above and the PSN
   layer below.

   The PSN layer provides PSN-specific modules for each type of PSN.
   These modules associate the PW with one or more "tunnels" that carry
   the service over the PSN.  These modules are used to "glue" the PW
   service to the underlying PSN-specific MIB modules.  This document
   defines the MIB module for Ethernet PW over any PSN type.

   This module uses Textual Conventions (TCs) and objects as defined in
   [RFC2578], [RFC2579], [RFC2580], [RFC2863], [RFC4363], [RFC4502], and
   [RFC5601].

   The Etherlike-MIB [RFC3635] does not support virtual Ethernet ports;
   however, it is sometimes desired to manage the PW as an Ethernet port
   via the Etherlike-MIB.  This MIB module supports an option to
   recognize the PW as an ifIndex, enabling standard use of the
   Etherlike-MIB to manage the PW.

5.  Feature Checklist

   The PW Ethernet MIB module (PW-ENET-STD-MIB) is designed to satisfy
   the following requirements and constraints:

   -  The MIB module is designed to work with the PW-STD-MIB [RFC5601].

   -  The MIB module is agnostic to the PSN type.

   -  The MIB module supports various options for selecting Ethernet
      packets into the PW, as defined in [RFC4448].  These include
      port-based PW, VLAN-based PW, and VLAN-manipulated based (change,
      add, or remove) between the port to be emulated and the PW.

   -  In the case of an MPLS PSN, the MIB module supports the use of
      multiple PWs to carry the same Ethernet service.  These PWs can be
      used to support Label-Only-Inferred-PSC LSPs (L-LSPs) or EXP-
      Inferred-PSC LSPs (E-LSPs) that are from a single Class of Service
      (CoS), when mapping of the Ethernet user priority (PRI) bits to
      the PSN CoS is required.

   -  The MIB module enables both point-to-point Ethernet services and
      VPLS services as discussed in the L2VPN working group [RFC4664].

   -  The MIB module allows modeling of the PW as an Ethernet virtual
      port to be managed via existing Ethernet MIBs like Etherlike-MIB
      [RFC3635].

6.  PW ENET MIB Module Usage

   -  The PW table (pwTable) is used for all PW types (ATM, FR,
      Ethernet, SONET, etc.).  This table contains high-level generic
      parameters related to the PW creation.  A row is typically created
      by the operator (see [RFC5542] for other options) for each PW
      service.

   -  Based on the PSN type defined for the PW, rows are created in the
      PSN-specific module (for example, [RFC5602]) and associated to the
      pwTable by the common pwIndex.

   -  If the PW type is Ethernet or EthernetTagged a row is created by
      the agent in the pwEnetTable.

7.  PW-ENET Management Model

   The management model for the Ethernet PW is shown in Figure 1, and is
   based on the PW layering [RFC3985].

              +--------------------------------------+
              |                PE Device             |
              +--------------------------------------+
       Single |                 |                    |
       AC     |                 |      Single        | PW Instance
      <------>o   Forwarder     +      PW Instance   X<=========>
              |                 |                    |
              +--------------------------------------+
                                ^
                                |
                         May be modeled as
                             ifIndex

   Notation:   o   A physical CE-bound PE port.
               +   A PW IWF instance interface to the forwarder.
               X   A PE PSN-bound port.

                 Figure 1: A simple point-to-point service

   In the typical point-to-point service, the object pwEnetPortIfIndex
   associates the physical CE-bound PE port ('o') to the PW (it is
   allowed to have multiple PWs associated to the same physical port).
   This MIB module also manages some of the possible operations of the
   forwarder.

   In some models, it is convenient to model the forwarder virtual
   interface to a PW IWF instance ('+') as an ifIndex.  As discussed in
   [RFC5601], this is possible by using the PW ifType in the ifTable and
   indicating the ifIndex in the main pwTable.  In case of Ethernet PW,
   a virtual interface of ifType = etherLike will be assigned on top of
   the PW interface to enable statistics gathering and statuses and
   other management configuration tasks via existing tools.  This way,
   the PW instance is managed as virtual Ethernet interface in the PE.

   The model for using the PW in non-point-to-point applications, such
   as VPLS, is done with the same principle in mind, except that the
   creation of the tables is related typically to an auto-discovery
   process.

8.  Example of the PW-ENET MIB Module Usage

   Assume we would like to create a PW of type VLAN between two PEs, for
   VLAN value 5.

   -  Follows the example in [RFC5601], with pwType equals
      'ethernetTagged'.

   -  The agent creates a row in the pwEnetTable and a row in the
      pwEnetStatsTable for the specified pwIndex.  The pwEnetPwInstance
      is automatically set by the agent to the value of 1.

   -  The operator fills the following entries in the pwEnetTable:

         pwEnetPwVlan        5,
         pwEnetVlanMode      noChange,
         pwEnetPortVlan      5,

         pwEnetPortIfIndex   1001,
         pwEnetPwIfIndex     0, -- Not managed in the
                                -- Etherlike MIB module
         ...

   -  The PW is ready for forwarding when signaling has been
      accomplished successfully between the two peers.

9.  Service-Delimiting Modes

   This section describes how the MIB module supports point-to-point
   applications with various VLAN service-delimiting options on the
   original Ethernet port and the corresponding PW mode and VLAN values.
   If the PW is attached to VPLS service, the PW is associated to a
   virtual interface that is attached to a bridge or VPLS forwarder.
   The bridging function between local physical ports and virtual
   interfaces that are later associated to PWs is not handled via this
   MIB module.

   There are three main service types that are supported by this MIB
   module:

   (1)  Port mode: In this mode, the whole traffic from the port is
        mapped to the PW.

        A.  In the typical application, the packet is sent to the PW as
            is:

            pwEnetPwVlan        4095,
            pwEnetVlanMode      portMode,
            pwEnetPortVlan      4095,

            pwType              Ethernet,

        B.  It is possible to add a provider tag (value 10, for example)
            to the packet when it is sent over the PW:

            pwEnetPwVlan        10,
            pwEnetVlanMode      addVlan,
            pwEnetPortVlan      4095,

            pwType SHOULD be set to 'EthernetTagged'.

   (2)  Single VLAN: In this mode, only the first VLAN field on the
        packet from the physical port is the service-delimiting tag, as
        an example VLAN=5.  The following options of processing are
        possible:

        A.  One-to-one mapping: The service-delimiting tag is kept as is
            on the PW.

            pwEnetPwVlan        5,
            pwEnetVlanMode      noChange,
            pwEnetPortVlan      5,

            pwType SHOULD be set to 'EthernetTagged'.

        B.  VLAN change mapping: The service-delimiting tag changes its
            value (to the value of 6) on the PW.

            pwEnetPwVlan        6,
            pwEnetVlanMode      changeVlan,
            pwEnetPortVlan      5,

            pwType SHOULD be set to 'EthernetTagged'.

        C.  The service-delimiting tag is removed when the packet is
            sent to the PW.

            pwEnetPwVlan        4095,
            pwEnetVlanMode      removeVlan,
            pwEnetPortVlan      5,

            pwType SHOULD be set to 'EthernetTagged'.

            It should be noted that this mode is also applicable when
            the service-delimiting tag is a service provider tag (VLAN=5
            in this case), and the node removes this VLAN and maps the
            traffic to a single PW independent of the packet format on
            top of this VLAN.

        D.  Untagged packets mapped to a PW as is (packets with a VLAN
            field from the same port MAY be mapped to other PWs).

            pwEnetPwVlan        0,
            pwEnetVlanMode      noChange,
            pwEnetPortVlan      0,

            pwType MAY equal 'Ethernet' or 'EthernetTagged'.

        E.  Untagged packets mapped to a PW, and a VLAN field is added
            to the packet.

            pwEnetPwVlan        6,
            pwEnetVlanMode      addVlan,
            pwEnetPortVlan      0,

            pwType SHOULD be set to 'EthernetTagged'.

        F.  A provider VLAN (value 10) is added to packets arriving with
            VLAN value 5 before they are sent to the PW.

            pwEnetPwVlan        10,
            pwEnetVlanMode      addVlan,
            pwEnetPortVlan      5,

            pwType SHOULD be set to 'EthernetTagged'.

   (3)  Nested VLAN (QinQ): When only the first VLAN is the service-
        delimiting tag, one of the modes as described in 2) SHOULD be
        used.  If the service-delimiting tag is both the first VLAN and
        the second VLAN, the following option is supported by this MIB
        module:

        Assuming the provider VLAN tag equals 5 and the user VLAN tag
        equal 100, this traffic can be mapped to the PW without the
        provider tag by using the following configuration:

         pwEnetPwVlan        100,
         pwEnetVlanMode      removeVLAN,
         pwEnetPortVlan      5,

         It is RECOMMENDED that the pwType would equal 'EthernetTagged',
         but pwType equal to 'Ethernet' MAY be used as well.

        Packets with the same provider tag MAY be mapped to other PWs.

   (4)  Other scenarios are considered out of scope and should be
        handled by other MIB modules that manage the forwarder and the
        Native Service Processing (NSP) sections.

10.  Object Definitions

PW-ENET-STD-MIB DEFINITIONS ::= BEGIN

IMPORTS
   OBJECT-TYPE, MODULE-IDENTITY, Unsigned32, mib-2
       FROM SNMPv2-SMI                    -- [RFC2578]

   MODULE-COMPLIANCE, OBJECT-GROUP
       FROM SNMPv2-CONF                   -- [RFC2580]

   StorageType, RowStatus
       FROM SNMPv2-TC                     -- [RFC2579]

   InterfaceIndexOrZero
       FROM IF-MIB                        -- [RFC2863]

   ZeroBasedCounter32
       FROM RMON2-MIB                     -- [RFC4502]

   pwIndex
       FROM PW-STD-MIB                    -- [RFC5601]

   VlanIdOrAnyOrNone
       FROM Q-BRIDGE-MIB;                 -- [RFC4363]

pwEnetStdMIB MODULE-IDENTITY
    LAST-UPDATED "200906150000Z"  -- 15 June 2009 00:00:00 GMT

    ORGANIZATION "Pseudowire Edge-to-Edge Emulation (PWE3) Working
                 Group"

    CONTACT-INFO
         "David Zelig
          Email: davidz@oversi.com

          Thomas D. Nadeau
          Email:  tom.nadeau@bt.com
         "
    DESCRIPTION
        "This MIB module describes a model for managing Ethernet
         point-to-point pseudowire services over a Packet
         Switched Network (PSN).

         Copyright (c) 2009 IETF Trust and the persons identified
         as authors of the code.  All rights reserved.

         Redistribution and use in source and binary forms, with or
         without modification, are permitted provided that the following
         conditions are met:

         - Redistributions of source code must retain the above
           copyright notice, this list of conditions and the following
           disclaimer.

         - Redistributions in binary form must reproduce the above
           copyright notice, this list of conditions and the following
           disclaimer in the documentation and/or other materials
           provided with the distribution.

         - Neither the name of Internet Society, IETF or IETF Trust, nor
           the names of specific contributors, may be used to endorse or
           promote products derived from this software without specific
           prior written permission.

         THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
         CONTRIBUTORS 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES,
         INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
         MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
         DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
         CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
         SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
         NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
         LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
         HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
         CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
         OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
         EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

         This version of this MIB module is part of RFC 5603;

         see the RFC itself for full legal notices."

   -- Revision history
   REVISION "200906150000Z"  -- 15 June 2009 00:00:00 GMT
   DESCRIPTION "Initial version published as part of RFC 5603."

      ::= { mib-2 180 }

pwEnetObjects        OBJECT IDENTIFIER ::= { pwEnetStdMIB 1 }
pwEnetConformance    OBJECT IDENTIFIER ::= { pwEnetStdMIB 2 }

--
-- Ethernet PW table
--

pwEnetTable  OBJECT-TYPE
    SYNTAX SEQUENCE OF PwEnetEntry
    MAX-ACCESS  not-accessible
    STATUS     current
    DESCRIPTION
        "This table contains the index to the Ethernet tables
        associated with this Ethernet PW, the VLAN configuration,
        and the VLAN mode."
    ::= { pwEnetObjects 1 }

pwEnetEntry  OBJECT-TYPE
    SYNTAX     PwEnetEntry
    MAX-ACCESS  not-accessible
    STATUS     current
    DESCRIPTION
        "This table is indexed by the same index that was created
        for the associated entry in the PW generic table in the

        PW-STD-MIB module.
        The pwIndex and the pwEnetPwInstance are used as indexes
        to allow multiple VLANs to exist on the same PW.

        An entry is created in this table by the agent for every
        entry in the pwTable with a pwType of 'ethernetTagged'
        or 'ethernet'.  Additional rows may be created by the
        operator or the agent if multiple entries are required for
        the same PW.

        The value of pwEnetPwInstance can be arbitrarily selected
        to make the row unique; however, implementations that know
        the VLAN field value when the row is created MAY use the
        value of the VLAN itself for better readability and
        backward compatibility with older versions of this MIB

        module.

        This table provides Ethernet port mapping and VLAN
        configuration for each Ethernet PW.

        All read-create objects in this table MAY be changed at any
        time; however, change of some objects (for example,
        pwEnetVlanMode) during the PW forwarding state MAY cause traffic
        disruption.

        Manual entries in this table SHOULD be preserved after a
        reboot, and the agent MUST ensure the integrity of those
        entries.  If the set of entries of a specific row is found to
        be inconsistent after reboot, the PW pwOperStatus MUST be
        declared as notPresent(5).
        "

    INDEX { pwIndex, pwEnetPwInstance }
    ::= { pwEnetTable 1 }

PwEnetEntry ::= SEQUENCE {
       pwEnetPwInstance    Unsigned32,
       pwEnetPwVlan        VlanIdOrAnyOrNone,
       pwEnetVlanMode      INTEGER,
       pwEnetPortVlan      VlanIdOrAnyOrNone,

       pwEnetPortIfIndex   InterfaceIndexOrZero,
       pwEnetPwIfIndex     InterfaceIndexOrZero,

       pwEnetRowStatus     RowStatus,
       pwEnetStorageType   StorageType
   }

pwEnetPwInstance  OBJECT-TYPE
    SYNTAX      Unsigned32
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "If multiple rows are mapped to the same PW, this index is
         used to uniquely identify the individual row.
         If the value of the VLAN field is known at the time of
         row creation, the value of pwEnetPwVlan MAY be used
         for better readability and backward compatibility with
         older versions of this MIB module.  Otherwise, the value
         1 SHOULD be set to the first row for each pwIndex
         for better readability and in order that the management
         application will know in advance how to access the
         first row when it was created by the agent.

        "
    ::= { pwEnetEntry 1 }

pwEnetPwVlan  OBJECT-TYPE
    SYNTAX      VlanIdOrAnyOrNone
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "This object defines the (service-delimiting) VLAN field
        value on the PW.  The value 4095 MUST be used if the
        object is not applicable, for example, when mapping all
        packets from an Ethernet port to this PW (raw mode).
        The value 0 MUST be set to indicate untagged frames
        (from the PW point of view), i.e., when pwEnetVlanMode
        equals 'noChange' and pwEnetPortVlan equals 0."
    ::= { pwEnetEntry 2 }

pwEnetVlanMode  OBJECT-TYPE
    SYNTAX     INTEGER {
             other(0),
             portBased(1),
             noChange(2),
             changeVlan(3),
             addVlan(4),
             removeVlan(5)
    }
    MAX-ACCESS  read-create
    STATUS     current
    DESCRIPTION
        "This object indicates the mode of VLAN handling between the
         port or the virtual port associated with the PW and the
         PW encapsulation.

       - 'other' indicates an operation that is not defined by
          this MIB module.

        - 'portBased' indicates that the forwarder will forward
          packets between the port and the PW independent of their
          structure (i.e., there are no service-delimiting VLAN tags
          from the PE standpoint).

        - 'noChange' indicates that the PW contains the original
           user VLAN, as specified in pwEnetPortVlan; i.e., the
           VLAN on the PE-CE link is the service-delimiting tag
           and is kept 'as is' on the PW.

        - 'changeVlan' indicates that the VLAN field on the PW
          may be different than the VLAN field on the user's

          port.  The VLAN on the PE-CE link is the service-delimiting
          tag but has a different value on the PW.

        - 'addVlan' indicates that a VLAN field will be added
          on the PSN-bound direction (i.e., on the PW). pwEnetPwVlan
          indicates the value that will be added.

        - 'removeVlan' indicates that the encapsulation on the
          PW does not include the service-delimiting VLAN field.
          Note that PRI bits transparency is lost in this case.

        - Implementation of 'portsbased', 'removeVlan', 'addVlan'
          'other', and 'changeVlan' is OPTIONAL.
        "
    DEFVAL { noChange }
    ::= { pwEnetEntry 3 }

pwEnetPortVlan  OBJECT-TYPE
    SYNTAX     VlanIdOrAnyOrNone
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "This object defines if the mapping between the original port
        (physical port or VPLS virtual port) to the PW is VLAN based
        or not.  In case of VLAN mapping, this object indicates the
        VLAN value on the original port.

        The value of '4095' MUST be used if the whole original port
        traffic is mapped to the same PW.  Note that a pwType of
        'ethernetTagged' can still be used if service-delimiting tag
        is added on the PW (pwEnetVlanMode equals 'addVlan').

        This object MUST be equal to pwEnetPwVlan if pwEnetVlanMode
        equals 'noChange'.

        The value 0 indicates that packets without a VLAN field
        (i.e., untagged frames) on the port are associated to this
        PW.  This allows the same behavior as assigning 'Default
        VLAN' to untagged frames.
        "
    DEFVAL  { 4095 }
    ::= { pwEnetEntry 4 }

pwEnetPortIfIndex  OBJECT-TYPE
    SYNTAX      InterfaceIndexOrZero
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION

        "This object is used to specify the ifIndex of the Ethernet
         port associated with this PW for point-to-point Ethernet
         service, or the ifIndex of the virtual interface of the
         VPLS instance associated with the PW if the service is
         VPLS.  Two rows in this table can point to the same ifIndex
         only if there is no overlap of VLAN values specified in
         pwEnetPortVlan that are associated with this port.

         A value of zero indicates that association to an ifIndex is
         not yet known."

    ::= { pwEnetEntry 5 }

pwEnetPwIfIndex  OBJECT-TYPE
    SYNTAX     InterfaceIndexOrZero
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "If the PW is modeled as an ifIndex in the ifTable, this
         object indicates the value of the ifIndex representing the
         Ethernet PW on the PSN side in the Etherlike-MIB.  Note that
         this value may be different from the value of pwIfIndex
         that represents the ifIndex of the PW for ifType 'pw'."
     DEFVAL { 0 }
    ::= { pwEnetEntry 6 }

pwEnetRowStatus  OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "This object enables creating, deleting, and modifying this
         row."
   ::= { pwEnetEntry 7 }

pwEnetStorageType  OBJECT-TYPE
    SYNTAX      StorageType
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "This object indicates the storage type of this row."
    DEFVAL { nonVolatile }
    ::= { pwEnetEntry 8 }

--
-- Ethernet PW Statistics Table
--

pwEnetStatsTable  OBJECT-TYPE
    SYNTAX SEQUENCE OF PwEnetStatsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "This table contains statistical counters specific for
         Ethernet PW."
    ::= { pwEnetObjects 2 }

pwEnetStatsEntry  OBJECT-TYPE
    SYNTAX      PwEnetStatsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "Each entry represents the statistics gathered for the
         PW carrying the Ethernet."
    INDEX { pwIndex }
    ::= { pwEnetStatsTable 1 }

PwEnetStatsEntry ::= SEQUENCE {
    pwEnetStatsIllegalVlan        ZeroBasedCounter32,
    pwEnetStatsIllegalLength      ZeroBasedCounter32
}

pwEnetStatsIllegalVlan  OBJECT-TYPE
    SYNTAX     ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS     current
    DESCRIPTION
        "The number of packets received (from the PSN) on this PW
         with either an illegal VLAN field, a missing VLAN field
         when one was expected, or an excessive VLAN field when
         it was not expected.  This counter may not be applicable
         in some cases, and MUST return the value of zero in
         such a case."
    ::= { pwEnetStatsEntry 1 }

pwEnetStatsIllegalLength  OBJECT-TYPE
    SYNTAX     ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS     current
    DESCRIPTION
        "The number of packets that were received with an illegal
         Ethernet packet length on this PW.  An illegal length is
         defined as being greater than the value in the advertised
         MTU supported, or shorter than the allowed Ethernet packet
         size."

    ::= { pwEnetStatsEntry 2 }

---
--- Conformance description
---

pwEnetGroups      OBJECT IDENTIFIER ::= { pwEnetConformance 1 }
pwEnetCompliances OBJECT IDENTIFIER ::= { pwEnetConformance 2 }

-- Compliance requirement for fully compliant implementations

pwEnetModuleFullCompliance MODULE-COMPLIANCE
    STATUS  current
    DESCRIPTION
            "The compliance statement for agents that provides full
             support for the PW-ENET-STD-MIB module.  Such devices
             can then be monitored and also be configured using
             this MIB module."
    MODULE  -- this module
      MANDATORY-GROUPS {
                         pwEnetGroup,
                         pwEnetStatsGroup
                        }

   OBJECT       pwEnetVlanMode
   DESCRIPTION "An implementation MUST support at least the value
                noChange(2)."

   OBJECT       pwEnetPwIfIndex
   MIN-ACCESS   read-only
   DESCRIPTION "Write access and values other than zero are
                required only for implementations that support
                modeling the Ethernet PW in the Etherlike-MIB."
   OBJECT       pwEnetRowStatus
   SYNTAX       RowStatus { active(1), notInService(2),
                            notReady(3) }
   WRITE-SYNTAX RowStatus { active(1), notInService(2),
                            createAndGo(4), destroy(6)
                          }
   MIN-ACCESS   read-only
   DESCRIPTION "Support for createAndWait is not required.  Support
                of notReady is not required for implementations that
                do not support signaling.
                Support of read-write is not required for
                implementations that do not support more than one
                VLAN mapping to the same PW."
    ::= { pwEnetCompliances 1 }

-- Compliance requirement for read-only compliant implementations

pwEnetModuleReadOnlyCompliance MODULE-COMPLIANCE
    STATUS  current
    DESCRIPTION
            "The compliance statement for agents that provide read-
             only support for the PW-ENET-STD-MIB module.  Such
             devices can then be monitored but cannot be configured
             using this MIB module."

    MODULE  -- this module
      MANDATORY-GROUPS { pwEnetGroup,
                         pwEnetStatsGroup
                         }

   OBJECT       pwEnetPwVlan
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required."

   OBJECT       pwEnetVlanMode
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required.  An implementation
                MUST support at least the value noChange(2)."

   OBJECT       pwEnetPortVlan
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required."

   OBJECT       pwEnetPortIfIndex
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required."

   OBJECT       pwEnetPwIfIndex
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required.  Values other than
                zero are required only for implementations that
                support modeling the Ethernet PW in the
                Etherlike-MIB."

   OBJECT       pwEnetRowStatus
   SYNTAX       RowStatus { active(1), notInService(2),
                            notReady(3) }
   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required.  Support
                of notReady is not required for implementations that
                do not support signaling."

   OBJECT       pwEnetStorageType

   MIN-ACCESS   read-only
   DESCRIPTION "Write access is not required."

    ::= { pwEnetCompliances 2 }

-- Units of conformance

pwEnetGroup OBJECT-GROUP
   OBJECTS {
            pwEnetPwVlan,
            pwEnetVlanMode,
            pwEnetPortVlan,
            pwEnetPortIfIndex,
            pwEnetPwIfIndex,
            pwEnetRowStatus,
            pwEnetStorageType
   }
   STATUS  current
   DESCRIPTION
       "Collection of objects for basic Ethernet PW configuration."
   ::= { pwEnetGroups 1 }

pwEnetStatsGroup OBJECT-GROUP
   OBJECTS {
            pwEnetStatsIllegalVlan,
            pwEnetStatsIllegalLength
   }
   STATUS  current
   DESCRIPTION
       "Collection of objects counting various PW level errors."
   ::= { pwEnetGroups 2 }

END

11.  Security Considerations

   It is clear that this MIB module is potentially useful for monitoring
   of PW-capable PEs.  This MIB module can also be used for
   configuration of certain objects, and anything that can be configured
   can be incorrectly configured, with potentially disastrous results.

   There are a number of management objects defined in this MIB module
   with a MAX-ACCESS clause of read-write and/or read-create.  Such
   objects may be considered sensitive or vulnerable in some network
   environments.  The support for SET operations in a non-secure
   environment without proper protection can have a negative effect on
   network operations.  These are the tables and objects and their
   sensitivity/vulnerability:

   o  the pwEnetTable contains objects to provision Ethernet PWs.
      Unauthorized access to objects in these tables could result in
      disruption of traffic on the network.  The use of stronger
      mechanisms such as SNMPv3 security should be considered where
      possible.  Specifically, SNMPv3 VACM and USM MUST be used with any
      v3 agent that implements this MIB module.  Administrators should
      consider whether read access to these objects should be allowed,
      since read access may be undesirable under certain circumstances.

   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:

   o  the pwEnetTable shows the Ethernet PW service configuration.  If
      an administrator does not want to reveal this information, then
      these tables should be considered sensitive/vulnerable.

   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.

   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 privacy).

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then 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.

12.  IANA Considerations

   The MIB module in this document uses the following IANA-assigned
   OBJECT IDENTIFIER value recorded in the SMI Numbers registry:

         Descriptor        OBJECT IDENTIFIER value
         ----------        -----------------------

         pwEnetStdMIB         { mib-2 180 }

13.  References

13.1.  Normative References

   [BCP14]    Bradner, S., "Key words for use in RFCs to Indicate
              requirement Levels", BCP 14, RFC 2119, March 1997.

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

   [RFC2579]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Textual Conventions for SMIv2", STD
              58, RFC 2579, April 1999.

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

   [RFC2863]  McCloghrie, K. and F. Kastenholz, "The Interfaces Group
              MIB", RFC 2863, June 2000.

   [RFC3635]  Flick, J., "Definitions of Managed Objects for the
              Ethernet-like Interface Types", RFC 3635, September 2003.

   [RFC4448]  Martini, L., Ed., Rosen, E., El-Aawar, N., and G. Heron,
              "Encapsulation Methods for Transport of Ethernet over MPLS
              Networks", RFC 4448, April 2006.

   [RFC4502]  Waldbusser, S., "Remote Network Monitoring Management
              Information Base Version 2", RFC 4502, May 2006.

   [RFC4363]  Levi, D. and D. Harrington, "Definitions of Managed
              Objects for Bridges with Traffic Classes, Multicast
              Filtering, and Virtual LAN Extensions", RFC 4363, January
              2006.

   [RFC5601]  Zelig, D., Ed., and T. Nadeau, Ed., "Pseudowire (PW)
              Management Information Base (MIB)", RFC 5601, July 2009.

13.2.  Informative References

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

   [RFC3916]  Xiao, X., Ed., McPherson, D., Ed., and P. Pate, Ed.,
              "Requirements for Pseudo-Wire Emulation Edge-to-Edge
              (PWE3)", RFC 3916, September 2004.

   [RFC3985]  Bryant, S., Ed., and P. Pate, Ed., "Pseudo Wire Emulation
              Edge-to-Edge (PWE3) Architecture", RFC 3985, March 2005.

   [RFC4664]  Andersson, L., Ed., and E. Rosen, Ed., "Framework for
              Layer 2 Virtual Private Networks (L2VPNs)", RFC 4664,
              September 2006.

   [RFC5542]  Nadeau, T., Ed., Zelig, D., Ed., and O. Nicklass, Ed.,
              "Definitions of Textual Conventions for Pseudowires (PW)
              Management", RFC 5542, May 2009.

   [RFC5602]  Zelig, D., Ed., and T. Nadeau, Ed., "Pseudowire (PW) over
              MPLS PSN Management Information Base (MIB)", RFC 5602,
              July 2009.

14.  Acknowledgments

   This document was produced by the PWE3 Working Group.  Special thanks
   to Orly Nicklass for close review and good suggestions.

Authors' Addresses

   David Zelig (editor)
   Oversi Networks
   1 Rishon Letzion St.
   Petah Tikva
   Israel

   Phone: +972 77 3337 750
   EMail: davidz@oversi.com

   Thomas D. Nadeau (editor)
   BT
   BT Centre
   81 Newgate Street
   London  EC1A 7AJ
   United Kingdom

   EMail: tom.nadeau@bt.com

 

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