Internet Engineering Task Force (IETF)                            Y. Cui
Request for Comments: 7856                                       J. Dong
Category: Standards Track                                          P. Wu
ISSN: 2070-1721                                                    M. Xu
                                                    Tsinghua University
                                                          A. Yla-Jaaski
                                                       Aalto University
                                                               May 2016


           Softwire Mesh 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 defines objects for managing a softwire mesh.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7856.

Copyright Notice

  Copyright (c) 2016 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
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.





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Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
  2.  The Internet-Standard Management Framework  . . . . . . . . .   2
  3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
  4.  Structure of the MIB Module . . . . . . . . . . . . . . . . .   3
    4.1.  The swmSupportedTunnelTable Subtree . . . . . . . . . . .   3
    4.2.  The swmEncapsTable Subtree  . . . . . . . . . . . . . . .   3
    4.3.  The swmBGPNeighborTable Subtree . . . . . . . . . . . . .   4
    4.4.  The swmConformance Subtree  . . . . . . . . . . . . . . .   4
  5.  Relationship to Other MIB Modules . . . . . . . . . . . . . .   4
    5.1.  Relationship to the IF-MIB  . . . . . . . . . . . . . . .   4
    5.2.  Relationship to the IP Tunnel MIB . . . . . . . . . . . .   5
    5.3.  MIB Modules Required for IMPORTS  . . . . . . . . . . . .   5
  6.  Definitions . . . . . . . . . . . . . . . . . . . . . . . . .   6
  7.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
  8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
  9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  15
    9.1.  Normative References  . . . . . . . . . . . . . . . . . .  15
    9.2.  Informative References  . . . . . . . . . . . . . . . . .  16
  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  17
  Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

  The softwire mesh framework [RFC5565] is a tunneling mechanism that
  enables connectivity between islands of IPv4 networks across a single
  IPv6 backbone and vice versa.  In a softwire mesh, extended
  Multiprotocol BGP (MP-BGP) is used to set up tunnels and advertise
  prefixes among Address Family Border Routers (AFBRs).

  This memo defines a portion of the Management Information Base (MIB)
  for use with network management protocols in the Internet community.
  In particular, it defines objects for managing a softwire mesh
  [RFC5565].

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 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




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  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.  Terminology

  This document uses terminology from the softwire problem statement
  [RFC4925], the BGP encapsulation Subsequent Address Family Identifier
  (SAFI), the BGP tunnel encapsulation attribute [RFC5512], the
  softwire mesh framework [RFC5565], and the BGP IPsec tunnel
  encapsulation attribute [RFC5566].

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in RFC
  2119 [RFC2119].

4.  Structure of the MIB Module

  The Softwire Mesh MIB provides a method to monitor the softwire mesh
  objects through SNMP.

4.1.  The swmSupportedTunnelTable Subtree

  The swmSupportedTunnelTable subtree provides the information about
  what types of tunnels can be used for softwire mesh scenarios in the
  AFBR.  The softwire mesh framework [RFC5565] does not mandate the use
  of any particular tunneling technology.  Based on the BGP tunnel
  encapsulation attribute tunnel types introduced by RFC 5512 [RFC5512]
  and RFC 5566 [RFC5566], the softwire mesh tunnel types include at
  least L2TPv3 (Layer 2 Tunneling Protocol version 3) over IP, GRE
  (Generic Routing Encapsulation), Transmit tunnel endpoint, IPsec in
  Tunnel-mode, IP in IP tunnel with IPsec Transport Mode, MPLS-in-IP
  tunnel with IPsec Transport Mode, and IP in IP.  The detailed
  encapsulation information of different tunnel types (e.g., L2TPv3
  Session ID, GRE Key, etc.) is not managed in the Softwire Mesh MIB.

4.2.  The swmEncapsTable Subtree

  The swmEncapsTable subtree provides softwire mesh NLRI-NH information
  (Network Layer Reachability Information - Next Hop) about the AFBR.
  It keeps the mapping between the External-IP (E-IP) prefix and the
  Internal-IP (I-IP) address of the next hop.  The mappings determine
  which I-IP destination address will be used to encapsulate the
  received packet according to its E-IP destination address.  The
  definitions of E-IP and I-IP are explained in Section 4.1 of RFC 5565
  [RFC5565].  The number of entries in swmEncapsTable shows how many
  softwire mesh tunnels are maintained in this AFBR.



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4.3.  The swmBGPNeighborTable Subtree

  This subtree provides the softwire mesh BGP neighbor information of
  an AFBR.  It includes the address of the softwire mesh BGP peer and
  the kind of tunnel that the AFBR would use to communicate with this
  BGP peer.

4.4.  The swmConformance Subtree

  This subtree provides the conformance information of MIB objects.

5.  Relationship to Other MIB Modules

5.1.  Relationship to the IF-MIB

  The Interfaces MIB [RFC2863] defines generic managed objects for
  managing interfaces.  Each logical interface (physical or virtual)
  has an ifEntry.  Tunnels are handled by creating logical interfaces
  (ifEntry).  Being a tunnel, the softwire mesh interface has an entry
  in the Interface MIB, as well as an entry in the IP Tunnel MIB.
  Those corresponding entries are indexed by ifIndex.

  The ifOperStatus in the ifTable represents whether the mesh function
  of the AFBR has been triggered.  If the softwire mesh capability is
  negotiated during the BGP OPEN phase, the mesh function is considered
  to be started, and the ifOperStatus is "up".  Otherwise, the
  ifOperStatus is "down".

  In the case of an IPv4-over-IPv6 softwire mesh tunnel, ifInUcastPkts
  counts the number of IPv6 packets that are sent to the virtual
  interface for decapsulation into IPv4.  The ifOutUcastPkts counts the
  number of IPv6 packets that are generated by encapsulating IPv4
  packets sent to the virtual interface.  In particular, if these IPv4
  packets need fragmentation, ifOutUcastPkts counts the number of
  packets after fragmentation.

  In the case of an IPv6-over-IPv4 softwire mesh tunnel, ifInUcastPkts
  counts the number of IPv4 packets that are delivered to the virtual
  interface for decapsulation into IPv6.  The ifOutUcastPkts counts the
  number of IPv4 packets that are generated by encapsulating IPv6
  packets sent down to the virtual interface.  In particular, if these
  IPv6 packets need to be fragmented, ifOutUcastPkts counts the number
  of packets after fragmentation.  Similar definitions apply to other
  counter objects in the ifTable.







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5.2.  Relationship to the IP Tunnel MIB

  The IP Tunnel MIB [RFC4087] contains objects applicable to all IP
  tunnels, including softwire mesh tunnels.  Meanwhile, the Softwire
  Mesh MIB extends the IP Tunnel MIB to further describe encapsulation-
  specific information.

  When running a point-to-multipoint tunnel, it is necessary for a
  softwire mesh AFBR to maintain an encapsulation table in order to
  perform correct "forwarding" among AFBRs.  This forwarding function
  on an AFBR is performed by using the E-IP destination address to look
  up the I-IP encapsulation destination address in the encapsulation
  table.  An AFBR also needs to know the BGP peer information of the
  other AFBRs, so that it can negotiate the NLRI-NH information and the
  tunnel parameters with them.

  The Softwire Mesh MIB requires the implementation of the IP Tunnel
  MIB.  The tunnelIfEncapsMethod in the tunnelIfEntry MUST be set to
  softwireMesh(16), and a corresponding entry in the Softwire Mesh MIB
  module will be presented for the tunnelIfEntry.  The
  tunnelIfRemoteInetAddress MUST be set to "0.0.0.0" for IPv4 or "::"
  for IPv6 because it is a point-to-multipoint tunnel.

  The tunnelIfAddressType in the tunnelIfTable represents the type of
  address in the corresponding tunnelIfLocalInetAddress and
  tunnelIfRemoteInetAddress objects.  The tunnelIfAddressType is
  identical to swmEncapsIIPDstType in softwire mesh, which can support
  either IPv4-over-IPv6 or IPv6-over-IPv4.  When the
  swmEncapsEIPDstType is IPv6 and the swmEncapsIIPDstType is IPv4, the
  tunnel type is IPv6-over-IPv4; when the swmEncapsEIPDstType is IPv4
  and the swmEncapsIIPDstType is IPv6, the encapsulation mode is IPv4-
  over-IPv6.

5.3.  MIB Modules Required for IMPORTS

  The following MIB module IMPORTS objects from SNMPv2-SMI [RFC2578],
  SNMPv2-CONF [RFC2580], IF-MIB [RFC2863], and INET-ADDRESS-MIB
  [RFC4001].













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6.  Definitions

  SOFTWIRE-MESH-MIB DEFINITIONS ::= BEGIN

  IMPORTS
      MODULE-IDENTITY, OBJECT-TYPE, mib-2 FROM SNMPv2-SMI

      OBJECT-GROUP, MODULE-COMPLIANCE             FROM SNMPv2-CONF

      InetAddress, InetAddressType, InetAddressPrefixLength

      FROM INET-ADDRESS-MIB

      ifIndex                                FROM IF-MIB

      IANAtunnelType                         FROM IANAifType-MIB;

      swmMIB MODULE-IDENTITY
      LAST-UPDATED "201605110000Z"        -- May 11, 2016
      ORGANIZATION "Softwire Working Group"
      CONTACT-INFO
               "Yong Cui
                Email:  [email protected]

                Jiang Dong
                Email:  [email protected]

                Peng Wu
                Email:  [email protected]

                Mingwei Xu
                Email:  [email protected]

                Antti Yla-Jaaski
                Email:  [email protected]

                Email comments directly to the Softwire WG Mailing
                List at [email protected]
               "
      DESCRIPTION
             "This MIB module contains managed object definitions for
              the softwire mesh framework.

              Copyright (c) 2016 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, is permitted pursuant to, and



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              subject to the license terms contained in, the Simplified
              BSD License set forth in Section 4.c of the IETF Trust's
              Legal Provisions Relating to IETF Documents
              (http://trustee.ietf.org/license-info)."
      REVISION    "201605110000Z"
      DESCRIPTION "Initial version, published as RFC 7856"
      ::= { mib-2 239 }

  swmObjects OBJECT IDENTIFIER ::= { swmMIB 1 }

  -- swmSupportedTunnelTable
  swmSupportedTunnelTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SwmSupportedTunnelEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A table of objects that show what kinds of tunnels
          can be supported by the AFBR."
      ::= { swmObjects 1 }

  swmSupportedTunnelEntry  OBJECT-TYPE
      SYNTAX      SwmSupportedTunnelEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A set of objects that show what kinds of tunnels
          can be supported in the AFBR.  If the AFBR supports
          multiple tunnel types, the swmSupportedTunnelTable
          would have several entries."
      INDEX { swmSupportedTunnelType }
      ::= { swmSupportedTunnelTable 1 }

  SwmSupportedTunnelEntry ::= SEQUENCE {
      swmSupportedTunnelType              IANAtunnelType
  }

  swmSupportedTunnelType OBJECT-TYPE
      SYNTAX      IANAtunnelType
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "Represents the tunnel type that can be used for softwire
          mesh scenarios, such as L2TPv3 over IP, GRE, Transmit
          tunnel endpoint, IPsec in Tunnel-mode, IP in IP tunnel with
          IPsec Transport Mode, MPLS-in-IP tunnel with IPsec Transport
          Mode, and IP in IP.  There is no restriction on the tunnel
          type the softwire mesh can use."
       REFERENCE



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          "L2TPv3 over IP, GRE, and IP in IP in RFC 5512.
          Transmit tunnel endpoint, IPsec in Tunnel-mode, IP in IP
          tunnel with IPsec Transport Mode, MPLS-in-IP tunnel with
          IPsec Transport Mode in RFC 5566."
      ::= { swmSupportedTunnelEntry 1 }

  -- end of swmSupportedTunnelTable

  --swmEncapsTable
  swmEncapsTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SwmEncapsEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A table of objects that display the
          softwire mesh encapsulation information."
      ::= { swmObjects 2 }

  swmEncapsEntry  OBJECT-TYPE
      SYNTAX      SwmEncapsEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A table of objects that manage the softwire mesh I-IP
           encapsulation destination based on the E-IP destination
           prefix."
      INDEX { ifIndex,
              swmEncapsEIPDstType,
              swmEncapsEIPDst,
              swmEncapsEIPPrefixLength
            }
      ::= { swmEncapsTable 1 }

  SwmEncapsEntry ::=      SEQUENCE {
      swmEncapsEIPDstType       InetAddressType,
      swmEncapsEIPDst           InetAddress,
      swmEncapsEIPPrefixLength  InetAddressPrefixLength,
      swmEncapsIIPDstType       InetAddressType,
      swmEncapsIIPDst           InetAddress
  }

  swmEncapsEIPDstType OBJECT-TYPE
      SYNTAX      InetAddressType
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This object specifies the address type used for
          swmEncapsEIPDst.  It is different from the



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          tunnelIfAddressType in the tunnelIfTable.  The
          swmEncapsEIPDstType is IPv6 (2) if it is IPv6-over-IPv4
          tunneling.  The swmEncapsEIPDstType is
          IPv4 (1) if it is IPv4-over-IPv6 tunneling."
      REFERENCE
          "IPv4 and IPv6 in RFC 4001."
      ::= { swmEncapsEntry 1 }

  swmEncapsEIPDst OBJECT-TYPE
      SYNTAX      InetAddress
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The E-IP destination prefix, which is
          used for I-IP encapsulation destination looking up.
          The type of this address is determined by the
          value of swmEncapsEIPDstType"
      REFERENCE
          "E-IP and I-IP in RFC 5565."
      ::= { swmEncapsEntry 2 }

  swmEncapsEIPPrefixLength OBJECT-TYPE
      SYNTAX      InetAddressPrefixLength
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The prefix length of the E-IP destination prefix."
      ::= { swmEncapsEntry 3 }

  swmEncapsIIPDstType OBJECT-TYPE
      SYNTAX      InetAddressType
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "This object specifies the address type used for
           swmEncapsIIPDst.  It is the same as the tunnelIfAddressType
           in the tunnelIfTable."
      REFERENCE
          "IPv4 and IPv6 in RFC 4001."
      ::= { swmEncapsEntry 4 }

  swmEncapsIIPDst OBJECT-TYPE
      SYNTAX      InetAddress
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "The I-IP destination address, which is used as the
          encapsulation destination for the corresponding E-IP



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          prefix.  Since the tunnelIfRemoteInetAddress in the
          tunnelIfTable should be 0.0.0.0 or ::, swmEncapIIPDst
          should be the destination address used in the outer
          IP header."
      REFERENCE
          "E-IP and I-IP in RFC 5565."
      ::= { swmEncapsEntry 5 }
  -- End of swmEncapsTable

  -- swmBGPNeighborTable
  swmBGPNeighborTable OBJECT-TYPE
      SYNTAX      SEQUENCE OF SwmBGPNeighborEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A table of objects that display the softwire mesh
          BGP neighbor information."
      ::= { swmObjects 3 }

  swmBGPNeighborEntry  OBJECT-TYPE
      SYNTAX      SwmBGPNeighborEntry
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "A set of objects that display the softwire mesh
          BGP neighbor information."
      INDEX {
              ifIndex,
              swmBGPNeighborInetAddressType,
              swmBGPNeighborInetAddress
            }
      ::= { swmBGPNeighborTable 1 }

  SwmBGPNeighborEntry ::= SEQUENCE {
          swmBGPNeighborInetAddressType    InetAddressType,
          swmBGPNeighborInetAddress        InetAddress,
          swmBGPNeighborTunnelType         IANAtunnelType
  }

  swmBGPNeighborInetAddressType OBJECT-TYPE
      SYNTAX      InetAddressType
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "This object specifies the address type used for
           swmBGPNeighborInetAddress."
      ::= { swmBGPNeighborEntry 1 }




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  swmBGPNeighborInetAddress OBJECT-TYPE
      SYNTAX      InetAddress
      MAX-ACCESS  not-accessible
      STATUS      current
      DESCRIPTION
          "The address of the AFBR's BGP neighbor.  The
          address type is the same as the tunnelIfAddressType
          in the tunnelIfTable."
      ::= { swmBGPNeighborEntry 2 }

  swmBGPNeighborTunnelType OBJECT-TYPE
      SYNTAX      IANAtunnelType
      MAX-ACCESS  read-only
      STATUS      current
      DESCRIPTION
          "Represents the type of tunnel that the AFBR
          chooses to transmit traffic with another AFBR/BGP
          neighbor."
      ::= { swmBGPNeighborEntry 3 }
  -- End of swmBGPNeighborTable


  -- conformance information
  swmConformance
                      OBJECT IDENTIFIER ::= { swmMIB 2 }
  swmCompliances
                      OBJECT IDENTIFIER ::= { swmConformance 1 }
  swmGroups
                      OBJECT IDENTIFIER ::= { swmConformance 2 }

   -- compliance statements
  swmCompliance MODULE-COMPLIANCE
     STATUS current
     DESCRIPTION
         "Describes the requirements for conformance to the Softwire
         Mesh MIB.

         The following index objects cannot be added as OBJECT
         clauses but nevertheless have compliance requirements:
         "
         -- OBJECT  swmEncapsEIPDstType
         -- SYNTAX  InetAddressType { ipv4(1), ipv6(2) }
         -- DESCRIPTION
         -- "An implementation is required to support
         --  global IPv4 and/or IPv6 addresses, depending
         --  on its support for IPv4 and IPv6."

         -- OBJECT  swmEncapsEIPDst



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         -- SYNTAX  InetAddress (SIZE(4|16))
         -- DESCRIPTION
         -- "An implementation is required to support
         --  global IPv4 and/or IPv6 addresses, depending
         --  on its support for IPv4 and IPv6."

         -- OBJECT  swmEncapsEIPPrefixLength
         -- SYNTAX  InetAddressPrefixLength (Unsigned32 (0..128))
         -- DESCRIPTION
         -- "An implementation is required to support
         --  global IPv4 and/or IPv6 addresses, depending
         --  on its support for IPv4 and IPv6."

         -- OBJECT  swmBGPNeighborInetAddressType
         -- SYNTAX  InetAddressType { ipv4(1), ipv6(2) }
         -- DESCRIPTION
         -- "An implementation is required to support
         --  global IPv4 and/or IPv6 addresses, depending
         --  on its support for IPv4 and IPv6."

         -- OBJECT  swmBGPNeighborInetAddress
         -- SYNTAX  InetAddress (SIZE(4|16))
         -- DESCRIPTION
         -- "An implementation is required to support
         --  global IPv4 and/or IPv6 addresses, depending
         --  on its support for IPv4 and IPv6."

     MODULE -- this module
     MANDATORY-GROUPS    {
                           swmSupportedTunnelGroup,
                           swmEncapsGroup,
                           swmBGPNeighborGroup
                         }
     ::= { swmCompliances 1 }

  swmSupportedTunnelGroup    OBJECT-GROUP
     OBJECTS {
         swmSupportedTunnelType
     }
     STATUS  current
     DESCRIPTION
         "The collection of objects that are used to show
         what kind of tunnel the AFBR supports."
     ::= { swmGroups 1 }

  swmEncapsGroup    OBJECT-GROUP
     OBJECTS {
          swmEncapsIIPDst,



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          swmEncapsIIPDstType
     }
     STATUS  current
     DESCRIPTION
         "The collection of objects that are used to display
         softwire mesh encapsulation information."
     ::= { swmGroups 2 }

  swmBGPNeighborGroup    OBJECT-GROUP
     OBJECTS {
          swmBGPNeighborTunnelType
     }
     STATUS  current
     DESCRIPTION
         "The collection of objects that are used to display
          softwire mesh BGP neighbor information."
     ::= { swmGroups 3 }

  END

7.  Security Considerations

  Because this MIB module reuses the IP Tunnel MIB, the security
  considerations of the IP Tunnel MIB are also applicable to the
  Softwire Mesh MIB.

  There are no management objects defined in this MIB module that have
  a MAX-ACCESS clause of read-write and/or read-create.  So, if this
  MIB module is implemented correctly, then 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 objects and their sensitivity/
  vulnerability:

  swmSupportedTunnelType, swmEncapsIIPDstType, swmEncapsIIPDst, and
  swmBGPNeighborTunnelType can expose the types of tunnels used within
  the internal network and potentially reveal the topology of the
  internal network.







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  SNMP versions prior to SNMPv3 did not include adequate security.
  Even if the network itself is secure (for example by using IPsec),
  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.

  Implementations SHOULD provide the security features described by the
  SNMPv3 framework (see [RFC3410]), and implementations claiming
  compliance to the SNMPv3 standard MUST include full support for
  authentication and privacy via the User-based Security Model (USM)
  [RFC3414] with the AES cipher algorithm [RFC3826].  Implementations
  MAY also provide support for the Transport Security Model (TSM)
  [RFC5591] in combination with a secure transport such as SSH
  [RFC5592] or TLS/DTLS [RFC6353].

  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.

8.  IANA Considerations

  IANA has allocated the following OBJECT IDENTIFIER value and recorded
  it in the SMI Numbers registry in the subregistry called "SMI Network
  Management MGMT Codes Internet-standard MIB" under the mib-2 branch
  (1.3.6.1.2.1):

          Descriptor        OBJECT IDENTIFIER value
          ----------        -----------------------
          swmMIB            { mib-2 239 }

  IANA has recorded the following IANAtunnelType Textual Convention
  within the IANAifType-MIB:

          IANAtunnelType ::= TEXTUAL-CONVENTION
                SYNTAX     INTEGER {
                           softwireMesh(16)  -- softwire mesh tunnel
                           }










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9.  References

9.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <http://www.rfc-editor.org/info/rfc2119>.

  [RFC2578]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
             Schoenwaelder, Ed., "Structure of Management Information
             Version 2 (SMIv2)", STD 58, RFC 2578,
             DOI 10.17487/RFC2578, April 1999,
             <http://www.rfc-editor.org/info/rfc2578>.

  [RFC2579]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
             Schoenwaelder, Ed., "Textual Conventions for SMIv2",
             STD 58, RFC 2579, DOI 10.17487/RFC2579, April 1999,
             <http://www.rfc-editor.org/info/rfc2579>.

  [RFC2580]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
             Schoenwaelder, Ed., "Conformance Statements for SMIv2",
             STD 58, RFC 2580, DOI 10.17487/RFC2580, April 1999,
             <http://www.rfc-editor.org/info/rfc2580>.

  [RFC3414]  Blumenthal, U. and B. Wijnen, "User-based Security Model
             (USM) for version 3 of the Simple Network Management
             Protocol (SNMPv3)", STD 62, RFC 3414,
             DOI 10.17487/RFC3414, December 2002,
             <http://www.rfc-editor.org/info/rfc3414>.

  [RFC3826]  Blumenthal, U., Maino, F., and K. McCloghrie, "The
             Advanced Encryption Standard (AES) Cipher Algorithm in the
             SNMP User-based Security Model", RFC 3826,
             DOI 10.17487/RFC3826, June 2004,
             <http://www.rfc-editor.org/info/rfc3826>.

  [RFC4001]  Daniele, M., Haberman, B., Routhier, S., and J.
             Schoenwaelder, "Textual Conventions for Internet Network
             Addresses", RFC 4001, DOI 10.17487/RFC4001, February 2005,
             <http://www.rfc-editor.org/info/rfc4001>.

  [RFC5512]  Mohapatra, P. and E. Rosen, "The BGP Encapsulation
             Subsequent Address Family Identifier (SAFI) and the BGP
             Tunnel Encapsulation Attribute", RFC 5512,
             DOI 10.17487/RFC5512, April 2009,
             <http://www.rfc-editor.org/info/rfc5512>.




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  [RFC5565]  Wu, J., Cui, Y., Metz, C., and E. Rosen, "Softwire Mesh
             Framework", RFC 5565, DOI 10.17487/RFC5565, June 2009,
             <http://www.rfc-editor.org/info/rfc5565>.

  [RFC5566]  Berger, L., White, R., and E. Rosen, "BGP IPsec Tunnel
             Encapsulation Attribute", RFC 5566, DOI 10.17487/RFC5566,
             June 2009, <http://www.rfc-editor.org/info/rfc5566>.

  [RFC5591]  Harrington, D. and W. Hardaker, "Transport Security Model
             for the Simple Network Management Protocol (SNMP)",
             STD 78, RFC 5591, DOI 10.17487/RFC5591, June 2009,
             <http://www.rfc-editor.org/info/rfc5591>.

  [RFC5592]  Harrington, D., Salowey, J., and W. Hardaker, "Secure
             Shell Transport Model for the Simple Network Management
             Protocol (SNMP)", RFC 5592, DOI 10.17487/RFC5592, June
             2009, <http://www.rfc-editor.org/info/rfc5592>.

  [RFC6353]  Hardaker, W., "Transport Layer Security (TLS) Transport
             Model for the Simple Network Management Protocol (SNMP)",
             STD 78, RFC 6353, DOI 10.17487/RFC6353, July 2011,
             <http://www.rfc-editor.org/info/rfc6353>.

9.2.  Informative References

  [RFC2863]  McCloghrie, K. and F. Kastenholz, "The Interfaces Group
             MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
             <http://www.rfc-editor.org/info/rfc2863>.

  [RFC3410]  Case, J., Mundy, R., Partain, D., and B. Stewart,
             "Introduction and Applicability Statements for Internet-
             Standard Management Framework", RFC 3410,
             DOI 10.17487/RFC3410, December 2002,
             <http://www.rfc-editor.org/info/rfc3410>.

  [RFC4087]  Thaler, D., "IP Tunnel MIB", RFC 4087,
             DOI 10.17487/RFC4087, June 2005,
             <http://www.rfc-editor.org/info/rfc4087>.

  [RFC4925]  Li, X., Ed., Dawkins, S., Ed., Ward, D., Ed., and A.
             Durand, Ed., "Softwire Problem Statement", RFC 4925,
             DOI 10.17487/RFC4925, July 2007,
             <http://www.rfc-editor.org/info/rfc4925>.








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Acknowledgements

  The authors would like to thank Dave Thaler, Jean-Philippe Dionne, Qi
  Sun, Sheng Jiang, and Yu Fu for their valuable comments.

Authors' Addresses

  Yong Cui
  Tsinghua University
  Department of Computer Science, Tsinghua University
  Beijing  100084
  China

  Phone: +86-10-6260-3059
  Email: [email protected]


  Jiang Dong
  Tsinghua University
  Department of Computer Science, Tsinghua University
  Beijing  100084
  China

  Phone: +86-10-6278-5822
  Email: [email protected]


  Peng Wu
  Tsinghua University
  Department of Computer Science, Tsinghua University
  Beijing  100084
  China

  Phone: +86-10-6278-5822
  Email: [email protected]


  Mingwei Xu
  Tsinghua University
  Department of Computer Science, Tsinghua University
  Beijing  100084
  China

  Phone: +86-10-6278-5822
  Email: [email protected]






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  Antti Yla-Jaaski
  Aalto University
  Konemiehentie 2
  Espoo  02150
  Finland

  Phone: +358-40-5954222
  Email: [email protected]











































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