rfc2074.txt

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Network Working Group                                       A. Bierman
Request for Comments: 2074                               Cisco Systems
Category: Standards Track                                     R. Iddon
                                                    AXON Networks,Inc.
                                                          January 1997


           Remote Network Monitoring MIB Protocol Identifiers

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.

Table of Contents

1 Introduction ....................................................    3
2 The SNMP Network Management Framework ...........................    3
2.1 Object Definitions ............................................    3
3 Overview ........................................................    3
3.1 Terms .........................................................    4
3.2 Relationship to the Remote Network Monitoring MIB .............    6
3.3 Relationship to the Other MIBs ................................    6
4 Protocol Identifier Encoding ....................................    7
4.1 ProtocolDirTable INDEX Format Examples ........................    9
4.2 Protocol Identifier Macro Format ..............................   10
4.2.1 Mapping of the Protocol Name ................................   12
4.2.2 Mapping of the VARIANT-OF Clause ............................   13
4.2.3 Mapping of the PARAMETERS Clause ............................   13
4.2.3.1 Mapping of the 'countsFragments(0)' BIT ...................   14
4.2.3.2 Mapping of the 'tracksSessions(1)' BIT ....................   15
4.2.4 Mapping of the ATTRIBUTES Clause ............................   15
4.2.5 Mapping of the DESCRIPTION Clause ...........................   15
4.2.6 Mapping of the CHILDREN Clause ..............................   16
4.2.7 Mapping of the ADDRESS-FORMAT Clause ........................   16
4.2.8 Mapping of the DECODING Clause ..............................   16
4.2.9 Mapping of the REFERENCE Clause .............................   17
4.2.10 Evaluating a Protocol-Identifier INDEX .....................   17
5 Protocol Identifier Macros ......................................   18
5.1 Base Identifier Encoding ......................................   18
5.1.1 Protocol Identifier Functions ...............................   19
5.1.1.1 Function 0: No-op .........................................   19
5.1.1.2 Function 1: Protocol Wildcard Function ....................   19
5.2 Base Layer Protocol Identifiers ...............................   20
5.2.1 Ether2 Encapsulation ........................................   21



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5.2.2 LLC Encapsulation ...........................................   22
5.2.3 SNAP over LLC (OUI=000) Encapsulation .......................   23
5.2.4 SNAP over LLC (OUI != 000) Encapsulation ....................   24
5.2.5 IANA Assigned Protocols .....................................   25
5.2.5.1 IANA Assigned Protocol Identifiers ........................   27
5.3 L3: Children of Base Protocol Identifiers .....................   27
5.3.1 IP ..........................................................   28
5.3.2 IPX .........................................................   29
5.3.3 ARP .........................................................   30
5.3.4 IDP .........................................................   30
5.3.5 AppleTalk ARP ...............................................   31
5.3.6 AppleTalk ...................................................   31
5.4 L4: Children of L3 Protocols ..................................   32
5.4.1 ICMP ........................................................   32
5.4.2 TCP .........................................................   32
5.4.3 UDP .........................................................   33
5.5 L5: Application Layer Protocols ...............................   33
5.5.1 FTP .........................................................   33
5.5.1.1 FTP-DATA ..................................................   33
5.5.1.2 FTP Control ...............................................   34
5.5.2 Telnet ......................................................   34
5.5.3 SMTP ........................................................   34
5.5.4 DNS .........................................................   35
5.5.5 BOOTP .......................................................   35
5.5.5.1 Bootstrap Server Protocol .................................   35
5.5.5.2 Bootstrap Client Protocol .................................   35
5.5.6 TFTP ........................................................   36
5.5.7 HTTP ........................................................   36
5.5.8 POP3 ........................................................   36
5.5.9 SUNRPC ......................................................   37
5.5.10 NFS ........................................................   38
5.5.11 SNMP .......................................................   38
5.5.11.1 SNMP Request/Response ....................................   38
5.5.11.2 SNMP Trap ................................................   39
6 Acknowledgements ................................................   39
7 References ......................................................   40
8 Security Considerations .........................................   43
9 Authors' Addresses ..............................................   43













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1.  Introduction

   This memo defines an experimental portion of the Management
   Information Base (MIB) for use with network management protocols in
   the Internet community.  In particular, it describes the algorithms
   required to identify different protocol encapsulations managed with
   the Remote Network Monitoring MIB Version 2 [RMON2]. Although related
   to the original Remote Network Monitoring MIB [RFC1757], this
   document refers only to objects found in the RMON-2 MIB.

2.  The SNMP Network Management Framework

   The SNMP Network Management Framework presently consists of three
   major components.  They are:

o    the SMI, described in RFC 1902 [RFC1902], - the mechanisms used for
     describing and naming objects for the purpose of management.

o    the MIB-II, STD 17, RFC 1213 [RFC1213], - the core set of managed
     objects for the Internet suite of protocols.

o    the protocol, STD 15, RFC 1157 [RFC1157] and/or RFC 1905 [RFC1905],
     - the protocol for accessing managed information.

   Textual conventions are defined in RFC 1903 [RFC1903], and
   conformance statements are defined in RFC 1904 [RFC1904].

   The Framework permits new objects to be defined for the purpose of
   experimentation and evaluation.

2.1.  Object Definitions

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the subset of Abstract Syntax Notation One (ASN.1)
   defined in the SMI.  In particular, each object type is named by an
   OBJECT IDENTIFIER, an administratively assigned name.  The object
   type together with an object instance serves to uniquely identify a
   specific instantiation of the object.  For human convenience, we
   often use a textual string, termed the descriptor, to refer to the
   object type.

3.  Overview

   The RMON-2 MIB [RMON2] uses hierarchically formatted OCTET STRINGs to
   globally identify individual protocol encapsulations in the
   protocolDirTable.




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   This guide contains algorithms and examples of protocol identifier
   encapsulations for use as INDEX values in the protocolDirTable.

   This document is not intended to be an authoritative reference on the
   protocols described herein. Refer to the Official Internet Standards
   document [RFC1800], the Assigned Numbers document [RFC1700], or other
   appropriate RFCs, IEEE documents, etc. for complete and authoritative
   protocol information.

3.1.  Terms

   Several terms are used throughout this document, as well as in the
   RMON-2 MIB [RMON2], that should be introduced:

layer-identifier:
     An octet string fragment representing a particular protocol
     encapsulation layer. A string fragment identifying a particular
     protocol encapsulation layer. This string is exactly four octets,
     (except for the 'vsnap' base-layer identifier, which is exactly
     eight octets) encoded in network byte order. A particular protocol
     encapsulation can be identified by starting with a base layer
     encapsulation (see the 'Base Protocol Identifiers' section for more
     detail), and following the encoding rules specified in the CHILDREN
     clause and assignment section for that layer. Then repeat for each
     identified layer in the encapsulation. (See section 4.2.10
     'Evaluating a Protocol-Identifier INDEX' for more detail.)

protocol:
     A particular protocol layer, as specified by encoding rules in this
     document. Usually refers to a single layer in a given
     encapsulation. Note that this term is sometimes used in the RMON-2
     MIB [RMON2] to name a fully-specified protocol-identifier string.
     In such a case, the protocol-identifier string is named for its
     upper-most layer. A named protocol may also refer to any
     encapsulation of that protocol.

protocol-identifier string:
     An octet string representing a particular protocol encapsulation,
     as specified by encoding rules in this document. This string is
     identified in the RMON-2 MIB [RMON2] as the protocolDirID object. A
     protocol-identifier string is composed of one or more layer-
     identifiers.









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protocol-identifier macro:
     A group of formatted text describing a particular protocol layer,
     as used within the RMON-2 MIB [RMON2]. The macro serves several
     purposes:

     - Name the protocol for use within the RMON-2 MIB [RMON2].
     - Describe how the protocol is encoded into an octet string.
     - Describe how child protocols are identified (if applicable),
       and encoded into an octet string.
     - Describe which protocolDirParameters are allowed for the protocol.
     - Describe how the associated protocolDirType object is encoded
       for the protocol.
     - Provide reference(s) to authoritative documentation for the
       protocol.

protocol-variant-identifier macro:
     A group of formatted text describing a particular protocol layer,
     as used within the RMON-2 MIB [RMON2]. This protocol is a variant
     of a well known encapsulation that may be present in the
     protocolDirTable. This macro is used to document the IANA
     assigned protocols, which are needed to identify protocols which
     cannot be practically identified by examination of 'appropriate
     network traffic' (e.g. the packets which carry them). All other
     protocols (which can be identified by examination of appropriate
     network traffic) should be documented using the protocol-identifier
     macro. A protocol-variant-identifier is documented using the
     protocol-variant version of the protocol-identifier macro.

protocol-parameter:
     A single octet, corresponding to a specific layer-identifier in the
     protocol-identifier. This octet is a bit-mask indicating special
     functions or capabilities that this agent is providing for the
     corresponding protocol.

protocol-parameters string:
     An octet string, which contains one protocol-parameter for each
     layer-identifier in the protocol-identifier.  See the section
     'Mapping of the PARAMETERS Clause' for more detail.  This string is
     identified in the RMON-2 MIB [RMON2] as the protocolDirParameters
     object.

protocolDirTable INDEX:
     A protocol-identifier and protocol-parameters octet string pair
     that have been converted to an INDEX value, according to the
     encoding rules in in section 7.7 of RFC 1902 [RFC1902].






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pseudo-protocol:
     A convention or algorithm used only within this document for the
     purpose of encoding protocol-identifier strings.

3.2.  Relationship to the Remote Network Monitoring MIB

   This document is intended to identify possible string values for the
   OCTET STRING objects protocolDirID and protocolDirParameters.  Tables
   in the new Protocol Distribution, Host, and Matrix groups use a local
   INTEGER INDEX, in order to remain unaffected by changes in this
   document. Only the protocolDirTable uses the strings (protocolDirID
   and protocolDirParameters) described in this document.

   This document is not intended to limit the protocols that may be
   identified for counting in the RMON-2 MIB. Many protocol
   encapsulations, not explicitly identified in this document, may be
   present in an actual implementation of the protocolDirTable. Also,
   implementations of the protocolDirTable may not include all the
   protocols identified in the example section below.

   This document is intentionally separated from the MIB objects to
   allow frequent updates to this document without any republication of
   MIB objects.  Protocol Identifier macros submitted from the RMON
   working group and community at large (to the RMONMIB WG mailing list
   at '[e-mail]') will be collected and added to this document.

   Macros submissions will be collected in the IANA's MIB files under
   the directory "ftp://ftp.isi.edu/mib/rmonmib/rmon2_pi_macros/" and in
   the RMONMIB working group mailing list message archive file
   "ftp://ftp.cisco.com/ftp/rmonmib/rmonmib".

   This document does not discuss auto-discovery and auto-population of
   the protocolDirTable. This functionality is not explicitly defined by
   the RMON standard. An agent should populate the directory with
   'interesting' protocols--depending on the intended applications.

3.3.  Relationship to the Other MIBs

   The RMON Protocol Identifiers document is intended for use with the
   protocolDirTable within the RMON MIB. It is not relevant to any other
   MIB, or intended for use with any other MIB.










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4.  Protocol Identifier Encoding

   The protocolDirTable is indexed by two OCTET STRINGs, protocolDirID
   and protocolDirParameters. To encode the table index, each variable-
   length string is converted to an OBJECT IDENTIFIER fragment,
   according to the encoding rules in section 7.7 of RFC 1902 [RFC1902].
   Then the index fragments are simply concatenated. (Refer to figures
   1a - 1d below for more detail.)

   The first OCTET STRING (protocolDirID) is composed of one or more 4-
   octet "layer-identifiers". The entire string uniquely identifies a
   particular protocol encapsulation tree. The second OCTET STRING,