RFC2074

From RFC-Wiki

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.

Contents

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.

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.

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.

Overview

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

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.

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.

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.

pseudo-protocol:

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

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 '[email protected]') 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.

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.

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, (protocolDirParameters) which contains a corresponding number of 1- octet protocol-specific parameters, one for each 4-octet layer- identifier in the first string.

A protocol layer is normally identified by a single 32-bit value. Each layer-identifier is encoded in the ProtocolDirID OCTET STRING INDEX as four sub-components [ a.b.c.d ], where 'a' - 'd' represent each byte of the 32-bit value in network byte order. If a particular protocol layer cannot be encoded into 32 bits, (except for the 'vsnap' base layer) then it must be defined as a 'ianaAssigned' protocol (see below for details on IANA assigned protocols).

The following figures show the differences between the OBJECT IDENTIFIER and OCTET STRING encoding of the protocol identifier string.

               Fig. 1a
     protocolDirTable INDEX Format
     -----------------------------
 +---+--------------------------+---+---------------+
 | c !                          | c !  protocolDir  |
 | n !  protocolDirID           | n !  Parameters   |
 | t !                          | t !               |
 +---+--------------------------+---+---------------+
               Fig. 1b
     protocolDirTable OCTET STRING Format
     ------------------------------------
  protocolDirID
 +----------------------------------------+
 |                                        |
 |              4 * N octets              |
 |                                        |
 +----------------------------------------+
 protocolDirParameters
 +----------+
 |          |
 | N octets |
 |          |
 +----------+
                Fig. 1c
    protocolDirTable INDEX Format Example
    -------------------------------------
 protocolDirID                   protocolDirParameters
 +---+--------+--------+--------+--------+---+---+---+---+---+
 | c |  proto |  proto |  proto |  proto | c |par|par|par|par|
 | n |  base  |    L3  |   L4   |   L5   | n |ba-| L3| L4| L5|
 | t |(+flags)|        |        |        | t |se |   |   |   |
 +---+--------+--------+--------+--------+---+---+---+---+---+ subOID
 | 1 | 4 or 8 |    4   |    4   |    4   | 1 |1/2| 1 | 1 | 1 | count
 where N is the number of protocol-layer-identifiers required
 for the entire encapsulation of the named protocol. Note that
 the 'vsnap' base layer identifier is encoded into 8 sub-identifiers,
 All other protocol layers are either encoded into 4 sub-identifiers
 or encoded as a 'ianaAssigned' protocol.
                Fig. 1d
   protocolDirTable OCTET STRING Format Example
   --------------------------------------------
 protocolDirID
 +--------+--------+--------+--------+
 |  proto |  proto |  proto |  proto |
 |   base |    L3  |   L4   |   L5   |
 |        |        |        |        |
 +--------+--------+--------+--------+ octet
 | 4 or 8 |    4   |    4   |    4   | count
 protocolDirParameters
 +---+---+---+---+
 |par|par|par|par|
 |ba-| L3| L4| L5|
 |se |   |   |   |
 +---+---+---+---+ octet
 |1/2| 1 | 1 | 1 | count
 where N is the number of protocol-layer-identifiers required
 for the entire encapsulation of the named protocol. Note that
 the 'vsnap' base layer identifier is encoded into 8
 protocolDirID sub-identifiers and 2 protocolDirParameters
 sub-identifiers.

Although this example indicates four encapsulated protocols, in practice, any non-zero number of layer-identifiers may be present, theoretically limited only by OBJECT IDENTIFIER length restrictions, as specified in section 3.5 of RFC 1902 RFC1902.

Note that these two strings would not be concatenated together if ever returned in a GetResponse PDU, since they are different MIB objects. However, protocolDirID and protocolDirParameters are not currently readable MIB objects.

ProtocolDirTable INDEX Format Examples

-- HTTP; fragments counted from IP and above
ether2.ip.tcp.www-http =
   16.0.0.0.1.0.0.8.0.0.0.0.6.0.0.0.80.4.0.1.0.0
-- SNMP over UDP/IP over SNAP
snap.ip.udp.snmp =
   16.0.0.0.3.0.0.8.0.0.0.0.17.0.0.0.161.4.0.0.0.0
-- SNMP over IPX over SNAP
snap.ipx.snmp =
   12.0.0.0.3.0.0.129.55.0.0.144.15.3.0.0.0
-- SNMP over IPX over raw8023
-- ianaAssigned(ipxOverRaw8023(1)).snmp =
   12.0.0.0.5.0.0.0.1.0.0.155.15.3.0.0.0
-- IPX over LLC
llc.ipx =
   8.0.0.0.2.0.224.224.3.2.0.0
-- SNMP over UDP/IP over any link layer
-- wildcard-ether2.ip.udp.snmp
   16.1.0.0.1.0.0.8.0.0.0.0.17.0.0.0.161.4.0.0.0.0
-- IP over any link layer; base encoding is IP over ether2
-- wildcard-ether2.ip
   8.1.0.0.1.0.0.8.0.2.0.0

-- AppleTalk Phase 2 over ether2 -- ether2.atalk

  8.0.0.0.1.0.0.128.155.2.0.0

-- AppleTalk Phase 2 over vsnap -- vsnap(apple).atalk

  12.0.0.0.4.0.8.0.7.0.0.128.155.3.0.0.0

Protocol Identifier Macro Format

The following example is meant to introduce the protocol-identifier macro. (The syntax is not quite ASN.1.) This macro is used to represent both protocols and protocol-variants.

If the 'VariantOfPart' component of the macro is present, then the macro represents a protocol-variant instead of a protocol. A protocol- variant-identifier is used only for IANA assigned protocols, enumerated under the 'ianaAssigned' base-layer.

 RMON-PROTOCOL-IDENTIFIER MACRO ::=
 BEGIN
         PIMacroName "PROTOCOL-IDENTIFIER"
                 VariantOfPart
                 "PARAMETERS"   ParamPart
                 "ATTRIBUTES"   AttrPart
                 "DESCRIPTION"  Text
                 ChildDescrPart
                 AddrDescrPart
                 DecodeDescrPart
                 ReferPart
         "::=" "{" EncapsPart "}"
         PIMacroName ::=
             identifier
         VariantOfPart ::=
             "VARIANT-OF" identifier | empty
         ParamPart ::=
             "{" ParamList "}"
         ParamList ::=
             Params | empty
         Params ::=
             Param | Params "," Param
         Param ::=
             identifier "(" nonNegativeNumber ")"
         AttrPart ::=
             "{" AttrList "}"
         AttrList ::=
             Attrs | empty
         Attrs ::=
             Attr | Attrs "," Attr
         Attr ::=
             identifier "(" nonNegativeNumber ")"
         ChildDescrPart ::=
             "CHILDREN" Text | empty
         AddrDescrPart ::=
             "ADDRESS-FORMAT" Text | empty
         DecodeDescrPart ::=
             "DECODING" Text | empty
         ReferPart ::=
             "REFERENCE" Text | empty
         EncapsPart ::=
             "{" Encaps "}"
         Encaps ::=
             Encap | Encaps "," Encap
         Encap ::=
             BaseEncap | NormalEncap | VsnapEncap | IanaEncap
         BaseEncap ::=
             nonNegativeNumber
         NormalEncap ::=
             identifier nonNegativeNumber
         VsnapEncap ::=
             identifier "(" nonNegativeNumber ")" nonNegativeNumber
         IanaEncap ::=
             "ianaAssigned" nonNegativeNumber
             | "ianaAssigned" identifier
             | "ianaAssigned" identifier "(" nonNegativeNumber ")"
         Text ::=
             """" string """"
 END

Mapping of the Protocol Name

The 'PIMacroName' value should be a lower-case ASCII string, and contain the name or acronym identifying the protocol. NMS applications may treat protocol names as case-insensitive strings, and agent implementations must make sure the protocolDirTable does not contain any instances of the protocolDirDescr object which differ only in the case of one of more letters (if the identifiers are intended to represent different protocols).

It is possible that different encapsulations of the same protocol (which are represented by different entries in the protocolDirTable) will be assigned the same protocol name.

A protocol name should match the "most well-known" name or acronym for the indicated protocol. For example, the document indicated by the URL:

   ftp://ftp.isi.edu/in-notes/iana/assignments/protocol-numbers

defines IP Protocol field values, so protocol-identifier macros for children of IP should be given names consistent with the protocol names found in this authoritative document.

Mapping of the VARIANT-OF Clause

This clause is present for IANA assigned protocols only. It identifies the protocol-identifier macro that most closely represents this particular protocol, and is known as the "reference protocol". (A protocol-identifier macro must exist for the reference protocol.) When this clause is present in a protocol-identifier macro, the macro is called a 'protocol-variant-identifier'.

Any clause (e.g. CHILDREN, ADDRESS-FORMAT) in the reference protocol- identifier macro should not be duplicated in the protocol-variant- identifier macro, if the 'variant' protocols' semantics are identical for a given clause.

Since the PARAMETERS and ATTRIBUTES clauses must be present in a protocol-identifier, an empty 'ParamPart' and 'AttrPart' (i.e. "PARAMETERS {}") must be present in a protocol-variant-identifier macro, and the 'ParamPart' and 'AttrPart' found in the reference protocol- identifier macro examined instead.

Note that if a 'ianaAssigned' protocol is defined that is not a variant of any other documented protocol, then the protocol- identifier macro should be used instead of the protocol-variant- identifier version of the macro.

Mapping of the PARAMETERS Clause

The protocolDirParameters object provides an NMS the ability to turn on and off expensive probe resources. An agent may support a given parameter all the time, not at all, or subject to current resource load.

The PARAMETERS clause is a list of bit definitions which can be directly encoded into the associated ProtocolDirParameters octet in network byte order. Zero or more bit definitions may be present. Only bits 0-7 are valid encoding values. This clause defines the entire BIT set allowed for a given protocol. A conforming agent may choose to implement a subset of zero or more of these PARAMETERS.

By convention, the following common bit definitions are used by different protocols. These bit positions must not be used for other parameters. They should be reserved if not used by a given protocol. Bits are encoded in network-byte order.

     Table 3.1  Reserved PARAMETERS Bits
     ------------------------------------

Bit Name Description


0 countsFragments higher-layer protocols encapsulated within

                  this protocol will be counted correctly even
                  if this protocol fragments the upper layers
                  into multiple packets.

1 tracksSessions correctly attributes all packets of a protocol

                  which starts sessions on well known ports or
                  sockets and then transfers them to dynamically
                  assigned ports or sockets thereafter (e.g. TFTP).

The PARAMETERS clause must be present in all protocol-identifier macro declarations, but may be equal to zero (empty). Note that an NMS must determine if a given PARAMETER bit is supported by attempting to create the desired protocolDirEntry The associated ATTRIBUTE bits for 'countsFragments' and 'tracksSessions' do not exist.

Mapping of the 'countsFragments(0)' BIT

This bit indicates whether the probe is correctly attributing all fragmented packets of the specified protocol, even if individual frames carrying this protocol cannot be identified as such. Note that the probe is not required to actually present any re-assembled datagrams (for address-analysis, filtering, or any other purpose) to the NMS.

This bit may only be set in a protocolDirParameters octet which corresponds to a protocol that supports fragmentation and reassembly in some form. Note that TCP packets are not considered 'fragmented- streams' and so TCP is not eligible.

This bit may be set in at most one protocolDirParameters octet within a protocolDirTable INDEX.

Mapping of the 'tracksSessions(1)' BIT

The 'tracksSessions(1)' bit indicates whether frames which are part of remapped-sessions (e.g. TFTP download sessions) are correctly counted by the probe. For such a protocol, the probe must usually analyze all packets received on the indicated interface, and maintain some state information, (e.g. the remapped UDP port number for TFTP).

The semantics of the 'tracksSessions' parameter are independent of the other protocolDirParameters definitions, so this parameter may be combined with any other legal parameter configurations.

Mapping of the ATTRIBUTES Clause

The protocolDirType object provides an NMS with an indication of a probe's capabilities for decoding a given protocol, or the general attributes of the particular protocol.

The ATTRIBUTES clause is a list of bit definitions which are encoded into the associated instance of ProtocolDirType. The BIT definitions are specified in the SYNTAX clause of the protocolDirType MIB object.

     Table 3.2  Reserved ATTRIBUTES Bits
     ------------------------------------
 Bit Name              Description
 ---------------------------------------------------------------------
 0  hasChildren        indicates that there may be children of
                       this protocol defined in the protocolDirTable
                       (by either the agent or the manager).
 1  addressRecognitionCapable
                       indicates that this protocol can be used
                       to generate host and matrix table entries.

The ATTRIBUTES clause must be present in all protocol-identifier macro declarations, but may be empty.

Mapping of the DESCRIPTION Clause

The DESCRIPTION clause provides a textual description of the protocol identified by this macro. Notice that it should not contain details about items covered by the CHILDREN, ADDRESS-FORMAT, DECODING and REFERENCE clauses.

The DESCRIPTION clause must be present in all protocol-identifier macro declarations.

Mapping of the CHILDREN Clause

The CHILDREN clause provides a description of child protocols for protocols which support them. It has three sub-sections:

 -  Details on the field(s)/value(s) used to select the child protocol,
 and how that selection process is performed
 -  Details on how the value(s) are encoded in the protocol identifier
 octet string
 -  Details on how child protocols are named with respect to their
 parent protocol label(s)

The CHILDREN clause must be present in all protocol-identifier macro declarations in which the 'hasChildren(0)' BIT is set in the ATTRIBUTES clause.

Mapping of the ADDRESS-FORMAT Clause

The ADDRESS-FORMAT clause provides a description of the OCTET-STRING format(s) used when encoding addresses.

This clause must be present in all protocol-identifier macro declarations in which the 'addressRecognitionCapable(1)' BIT is set in the ATTRIBUTES clause.

Mapping of the DECODING Clause

The DECODING clause provides a description of the decoding procedure for the specified protocol. It contains useful decoding hints for the implementor, but should not over-replicate information in documents cited in the REFERENCE clause. It might contain a complete description of any decoding information required.

For 'extensible' protocols ('hasChildren(0)' BIT set) this includes offset and type information for the field(s) used for child selection as well as information on determining the start of the child protocol.

For 'addressRecognitionCapable' protocols this includes offset and type information for the field(s) used to generate addresses.

The DECODING clause is optional, and may be omitted if the REFERENCE clause contains pointers to decoding information for the specified protocol.

Mapping of the REFERENCE Clause

If a publicly available reference document exists for this protocol it should be listed here. Typically this will be a URL if possible; if not then it will be the name and address of the controlling body.

The CHILDREN, ADDRESS-FORMAT, and DECODING clauses should limit the amount of information which may currently be obtained from an 'authoritative' document, such as the Assigned Numbers document RFC1700. Any duplication or paraphrasing of information should be brief and consistent with the authoritative document.

The REFERENCE clause is optional, but should be implemented if an authoritative reference exists for the protocol (especially for standard protocols).

4.2.10. Evaluating a Protocol-Identifier INDEX

The following evaluation is done after protocolDirTable INDEX value has been converted into two OCTET STRINGs according to the INDEX encoding rules specified in the SMI RFC1902.

Protocol-identifiers are evaluated left to right, starting with the protocolDirID, which length should be evenly divisible by four. The protocolDirParameters length should be exactly one quarter of the protocolDirID string length.

Protocol-identifier parsing starts with the base layer identifier, which must be present, and continues for one or more upper layer identifiers, until all OCTETs of the protocolDirID have been used. Layers may not be skipped, so identifiers such as 'SNMP over IP' or 'TCP over anylink' can not exist.

The base-layer-identifier also contains a 'special function identifier' which may apply to the rest of the protocol identifier.

Wild-carding at the base layer within a protocol encapsulation is the only supported special function at this time. Refer to the 'Base Protocol Identifiers' section for wildcard encoding rules.

After the protocol-tree identified in protocolDirID has been parsed, each parameter bit-mask (one octet for each 4-octet layer-identifier) is evaluated, and applied to the corresponding protocol layer.

A protocol-identifier label may map to more than one value. For instance, 'ip' maps to 5 distinct values, one for each supported encapsulation. (see the 'IP' section under 'L3 Protocol Identifiers'),

It is important to note that these macros are conceptually expanded at implementation time, not at run time.

If all the macros are expanded completely by substituting all possible values of each label for each child protocol, a list of all possible protocol-identifiers is produced. So 'ip' would result in 5 distinct protocol-identifiers. Likewise each child of 'ip' would map to at least 5 protocol-identifiers, one for each encapsulation (e.g. ip over ether2, ip over LLC, etc.).

Protocol Identifier Macros

The following PROTOCOL IDENTIFIER macros can be used to construct protocolDirID and protocolDirParameters strings.

The sections defining protocol examples are intended to grow over subsequent releases. Minimal protocol support is included at this time. (Refer to section 3.2 for details on the protocol macro update procedure.)

An identifier is encoded by constructing the base-identifier, then adding one layer-identifier for each encapsulated protocol.

Base Identifier Encoding

The first layer encapsulation is called the base identifier and it contains optional protocol-function information and the base layer (e.g. MAC layer) enumeration value used in this protocol identifier.

The base identifier is encoded as four octets as shown in figure 2.

      Fig. 2
 base-identifier format
 +---+---+---+---+
 |   |   |   |   |
 | f |op1|op2| m |
 |   |   |   |   |
 +---+---+---+---+ octet
 | 1 | 1 | 1 | 1 | count

The first octet ('f') is the special function code, found in table 4.1. The next two octets ('op1' and 'op2') are operands for the indicated function. If not used, an operand must be set to zero. The last octet, 'm', is the enumerated value for a particular base layer encapsulation, found in table 4.2. All four octets are encoded in network-byte-order.

Protocol Identifier Functions

The base layer identifier contains information about any special functions to perform during collections of this protocol, as well as the base layer encapsulation identifier.

The first three octets of the identifier contain the function code and two optional operands. The fourth octet contains the particular base layer encapsulation used in this protocol (fig. 2).

 Table 4.1  Assigned Protocol Identifier Functions
 -------------------------------------------------
       Function     ID    Param1               Param2
       ----------------------------------------------------
       none          0    not used (0)         not used (0)
       wildcard      1    not used (0)         not used (0)
Function 0: No-op

If the function ID field (1st octet) is equal to zero, the the 'op1' and 'op2' fields (2nd and 3rd octets) must also be equal to zero. This special value indicates that no functions are applied to the protocol identifier encoded in the remaining octets. The identifier represents a normal protocol encapsulation.

Function 1: Protocol Wildcard Function

The wildcard function (function-ID = 1), is used to aggregate counters, by using a single protocol value to indicate potentially many base layer encapsulations of a particular network layer protocol. A protocolDirEntry of this type will match any base-layer encapsulation of the same protocol.

The 'op1' field (2nd octet) is not used and must be set to zero.

The 'op2' field (3rd octet) is not used and must be set to zero.

Each wildcard protocol identifier must be defined in terms of a 'base encapsulation'. This should be as 'standard' as possible for interoperability purposes. If an encapsulation over 'ether2' is permitted, than this should be used as the base encapsulation.

The agent may also be requested to count some or all of the individual encapsulations for the same protocols, in addition to wildcard counting. Note that the RMON-2 MIB [RMON2] does not require that agents maintain counters for multiple encapsulations of the same protocol. It is an implementation-specific matter as to how an agent determines which protocol combinations to allow in the protocolDirTable at any given time.

Base Layer Protocol Identifiers

The base layer is mandatory, and defines the base encapsulation of the packet and any special functions for this identifier.

There are no suggested protocolDirParameters bits for the base layer.

The suggested ProtocolDirDescr field for the base layer is given by the corresponding "Name" field in the table 4.1 below. However, implementations are only required to use the appropriate integer identifier values.

For most base layer protocols, the protocolDirType field should contain bits set for the 'hasChildren(0)' and 'addressRecognitionCapable(1)' attributes. However, the special 'ianaAssigned' base layer should have no parameter or attribute bits set.

By design, only 255 different base layer encapsulations are supported. There are five base encapsulation values defined at this time. New base encapsulations (e.g. for new media types) are expected to be added over time.

 Table 4.2  Base Layer Encoding Values
 --------------------------------------
       Name          ID
       ------------------
       ether2        1
       llc           2
       snap          3
       vsnap         4
       ianaAssigned    5

Ether2 Encapsulation

ether2 PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "DIX Ethernet, also called Ethernet-II."
CHILDREN
   "The Ethernet-II type field is used to select child protocols.
   This is a 16-bit field.  Child protocols are deemed to start at
   the first octet after this type field.
   Children of this protocol are encoded as [ 0.0.0.1 ], the
   protocol identifier for 'ether2' followed by [ 0.0.a.b ] where
   'a' and 'b' are the network byte order encodings of the MSB and
   LSB of the Ethernet-II type value.
   For example, a protocolDirID-fragment value of:
      0.0.0.1.0.0.8.0 defines IP encapsulated in ether2.
   Children of are named as 'ether2' followed by the type field
   value in hexadecimal.  The above example would be declared as:
      ether2 0x0800"
ADDRESS-FORMAT
   "Ethernet addresses are 6 octets in network order."
DECODING
   "Only type values greater than or equal to 1500 decimal indicate
   Ethernet-II frames; lower values indicate 802.3 encapsulation
   (see below)."
REFERENCE
   "A Standard for the Transmission of IP Datagrams over Ethernet
   Networks; RFC 894 RFC894.
   The authoritative list of Ether Type values is identified by the
   URL:
      ftp://ftp.isi.edu/in-notes/iana/assignments/ethernet-numbers"
::= { 1 }

LLC Encapsulation

llc PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "The LLC (802.2) protocol."
CHILDREN
   "The LLC SSAP and DSAP (Source/Dest Service Access Points) are
   used to select child protocols.  Each of these is one octet long,
   although the least significant bit is a control bit and should be
   masked out in most situations.  Typically SSAP and DSAP (once
   masked) are the same for a given protocol - each end implicitly
   knows whether it is the server or client in a client/server
   protocol.  This is only a convention, however, and it is possible
   for them to be different.  The SSAP is matched against child
   protocols first.  If none is found then the DSAP is matched
   instead.  The child protocol is deemed to start at the first
   octet after the LLC control field(s).
   Children of 'llc' are encoded as [ 0.0.0.2 ], the protocol
   identifier component for LLC followed by [ 0.0.0.a ] where 'a' is
   the SAP value which maps to the child protocol.  For example, a
   protocolDirID-fragment value of:
      0.0.0.2.0.0.0.240
   defines NetBios over LLC.
   Children are named as 'llc' followed by the SAP value in
   hexadecimal.  So the above example would have been named:
      llc 0xf0"
ADDRESS-FORMAT
   "The address consists of 6 octets of MAC address in network
   order.  Source routing bits should be stripped out of the address
   if present."
DECODING
   "Notice that LLC has a variable length protocol header; there are
   always three octets (DSAP, SSAP, control).  Depending on the
   value of the control bits in the DSAP, SSAP and control fields
   there may be an additional octet of control information.
   LLC can be present on several different media.  For 802.3 and
   802.5 its presence is mandated (but see ether2 and raw802.3
   encapsulations).  For 802.5 there is no other link layer
   protocol.
   Notice also that the raw802.3 link layer protocol may take
   precedence over this one in a protocol specific manner such that
   it may not be possible to utilize all LSAP values if raw802.3 is
   also present."
REFERENCE
   "The authoritative list of LLC LSAP values is controlled by the
   IEEE Registration Authority:
   IEEE Registration Authority
      c/o Iris Ringel
      IEEE Standards Dept
      445 Hoes Lane, P.O. Box 1331
      Piscataway, NJ 08855-1331
      Phone +1 908 562 3813
      Fax: +1 908 562 1571"
::= { 2 }

SNAP over LLC (OUI=000) Encapsulation

snap PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "The Sub-Network Access Protocol (SNAP) is layered on top of LLC
   protocol, allowing Ethernet-II protocols to be run over a media
   restricted to LLC."
CHILDREN
   "Children of 'snap' are identified by Ethernet-II type values;
   the SNAP PID (Protocol Identifier) field is used to select the
   appropriate child.  The entire SNAP protocol header is consumed;
   the child protocol is assumed to start at the next octet after
   the PID.
   Children of 'snap' are encoded as [ 0.0.0.3 ], the protocol
   identifier for 'snap', followed by [ 0.0.a.b ] where 'a' and 'b'
   are the MSB and LSB of the Ethernet-II type value.  For example,
   a protocolDirID-fragment value of:
      0.0.0.3.0.0.8.0
   defines the IP/SNAP protocol.
   Children of this protocol are named 'snap' followed by the
   Ethernet-II type value in hexadecimal.  The above example would
   be named:
      snap 0x0800"
ADDRESS-FORMAT
     "The address format for SNAP is the same as that for LLC"
DECODING
   "SNAP is only present over LLC.  Both SSAP and DSAP will be 0xAA
   and a single control octet will be present.  There are then three
   octets of OUI and two octets of PID.  For this encapsulation the
   OUI must be 0x000000 (see 'vsnap' below for non-zero OUIs)."
REFERENCE
   "SNAP Identifier values are assigned by the IEEE Standards
   Office.  The address is:
           IEEE Registration Authority
           c/o Iris Ringel
           IEEE Standards Dept
           445 Hoes Lane, P.O. Box 1331
           Piscataway, NJ 08855-1331
           Phone +1 908 562 3813
           Fax: +1 908 562 1571"
::= { 3 }

SNAP over LLC (OUI != 000) Encapsulation

vsnap PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "This pseudo-protocol handles all SNAP packets which do not have
   a zero OUI.  See 'snap' above for details of those that do."
CHILDREN
   "Children of 'vsnap' are selected by the 3 octet OUI; the PID is
   not parsed; child protocols are deemed to start with the first
   octet of the SNAP PID field, and continue to the end of the
   packet.
   Children of 'vsnap' are encoded as [ 0.0.0.4 ], the protocol
   identifier for 'vsnap', followed by [ 0.a.b.c.0.0.d.e ] where
   'a', 'b' and 'c' are the 3 octets of the OUI field in network
   byte order. This is in turn followed by the 16-bit EtherType
   value, where the 'd' and 'e' represent the MSB and LSB of the
   EtherType, respectively.
   For example, a protocolDirID-fragment value of:
     0.0.0.4.0.8.0.7.0.0.128.155
   defines the AppleTalk Phase 2 protocol over vsnap.
   Note that two protocolDirParameters octets must be present in
   protocolDirTable INDEX values for 'vsnap' protocols.  The first
   protocolDirParameters octet defines the actual parameters. The
   second protocolDirParameters octet is not used and must be set to
   zero.
   Children are named as 'vsnap(<OUI>) <ethertype>', where the
   '<OUI>' field is represented as 3 octets in hexadecimal notation
   or the ASCII string associated with the OUI value. The
   <ethertype> field is represented by the 2 byte EtherType value in
   hexadecimal notation. So the above example would be named:
     'vsnap(0x080007) 0x809b' or 'vsnap(apple) 0x809b'"
ADDRESS-FORMAT
   "The LLC address format is inherited by 'vsnap'.  See the 'llc'
   protocol identifier for more details."
DECODING
   "Same as for 'snap' except the OUI is non-zero."
REFERENCE
   "SNAP Identifier values are assigned by the IEEE Standards
   Office.  The address is:
           IEEE Registration Authority
           c/o Iris Ringel
           IEEE Standards Dept
           445 Hoes Lane, P.O. Box 1331
           Piscataway, NJ 08855-1331
           Phone +1 908 562 3813
           Fax: +1 908 562 1571"
::= { 4 }

IANA Assigned Protocols

ianaAssigned PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "This branch contains protocols which do not conform easily to
   the hierarchical format utilized in the other link layer
   branches.  Usually, such a protocol 'almost' conforms to a
   particular 'well-known' identifier format, but additional
   criteria are used (e.g. configuration-based), making protocol
   identification difficult or impossible by examination of
   appropriate network traffic.  preventing the any 'well-known'
   protocol-identifier macro from being used.
   Sometimes well-known protocols are simply remapped to a different
   port number by one or more venders (e.g. SNMP). These protocols
   can be identified with the 'user-extensibility' feature of the
   protocolDirTable, and do not need special IANA
   assignments.
   A centrally located list of these enumerated protocols must be
   maintained to insure interoperability.
   (See section 3.2 for details on the document update procedure.)
   Support for new link-layers will be added explicitly, and only
   protocols which cannot possibly be represented in a better way
   will be considered as 'ianaEnumerated' protocols.
   IANA assigned protocols are identified by the base-layer-selector
   value [ 0.0.0.5 ], followed by the four octets [ a.b.c.d ] of the
   integer value corresponding to the particular IANA protocol.
   Do not create children of this protocol unless you are sure that
   they cannot be handled by the more conventional link layers
   above."
CHILDREN
   "Children of this protocol are identified by implementation-
   specific means, described (as best as possible) in the 'DECODING'
   clause within the protocol-variant-identifier macro for each
   enumerated protocol.
   For example, a protocolDirID-fragment value of:
      0.0.0.5.0.0.0.1
   defines the IPX protocol encapsulated directly in 802.3
   Children are named 'ianaAssigned' followed by the name or numeric
   of the particular IANA assigned protocol. The above
   example would be named:
      'ianaAssigned 1' or 'ianaAssigned ipxOverRaw8023'"
DECODING
   "The 'ianaAssigned' base layer is a pseudo-protocol and is not
   decoded."
REFERENCE
   "Refer to individual PROTOCOL-IDENTIFIER macros for information
   on each child of the IANA assigned protocol."
::= { 5 }
IANA Assigned Protocol Identifiers

The following protocol-variant-identifier macro declarations are used to identify the RMONMIB IANA assigned protocols in a proprietary way, by simple enumeration. Note that an additional four-octet layer identifier may be used for some enumerations (as with the 'vsnap' base-layer identifier). Refer to the 'CHILDREN' clause in the protocol-identifier macro for a particular protocol to determine the number of octets in the 'ianaAssigned' layer-identifier.

ipxOverRaw8023 PROTOCOL-IDENTIFIER

VARIANT-OF  "ipx"
PARAMETERS  { }
ATTRIBUTES  { }
DESCRIPTION
   "This pseudo-protocol describes an encapsulation of IPX over
   802.3, without a type field.
   Refer to the macro for IPX for additional information about this
   protocol."
DECODING
   "Whenever the 802.3 header indicates LLC a set of protocol
   specific tests needs to be applied to determine whether this is a
   'raw8023' packet or a true 802.2 packet.  The nature of these
   tests depends on the active child protocols for 'raw8023' and is
   beyond the scope of this document."
::= { ianaAssigned 1 }

L3: Children of Base Protocol Identifiers

Network layer protocol identifier macros contain additional information about the network layer, and is found immediately following a base layer-identifier in a protocol identifier.

The ProtocolDirParameters supported at the network layer are 'countsFragments(0)', and 'tracksSessions(1). An agent may choose to implement a subset of these parameters.

The protocol-name should be used for the ProtocolDirDescr field. The ProtocolDirType ATTRIBUTES used at the network layer are 'hasChildren(0)' and 'addressRecognitionCapable(1)'. Agents may choose to implement a subset of these attributes for each protocol, and therefore limit which tables the indicated protocol can be present (e.g. protocol distribution, host, and matrix tables)..

The following protocol-identifier macro declarations are given for example purposes only. They are not intended to constitute an exhaustive list or an authoritative source for any of the protocol

information given. However, any protocol that can encapsulate other protocols must be documented here in order to encode the children identifiers into protocolDirID strings. Leaf protocols should be documented as well, but an implementation can identify a leaf protocol even if it isn't listed here (as long as the parent is documented).

IP

ip PROTOCOL-IDENTIFIER

PARAMETERS {
      countsFragments(0)  -- This parameter applies to all child
                          -- protocols.
}
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "The protocol identifiers for the Internet Protocol (IP). Note
   that IP may be encapsulated within itself, so more than one of
   the following identifiers may be present in a particular
   protocolDirID string."
CHILDREN
   "Children of 'ip' are selected by the value in the Protocol field
   (one octet), as defined in the PROTOCOL NUMBERS table within the
   Assigned Numbers Document.
   The value of the Protocol field is encoded in an octet string as
   [ 0.0.0.a ], where 'a' is the protocol field .
   Children of 'ip' are encoded as [ 0.0.0.a ], and named as 'ip a'
   where 'a' is the protocol field value. For example, a
   protocolDirID-fragment value of:
      0.0.0.1.0.0.8.0.0.0.0.1
   defines an encapsulation of ICMP (ether2.ip.icmp)"
ADDRESS-FORMAT
   "4 octets of the IP address, in network byte order.  Each ip
   packet contains two addresses, the source address and the
   destination address."
DECODING
   "Note: ether2/ip/ipip4/udp is a different protocolDirID than
   ether2/ip/udp, as identified in the protocolDirTable. As such,
   two different local protocol index values will be assigned by the
   agent. E.g. (full INDEX values shown):
    ether2/ip/ipip4/udp 16.0.0.0.1.0.0.8.0.0.0.0.4.0.0.0.17.4.0.0.0.0
    ether2/ip/udp       12.0.0.0.1.0.0.8.0.0.0.0.17.3.0.0.0 "
REFERENCE
   "RFC 791 RFC791 defines the Internet Protocol; The following
   URL defines the authoritative repository for the PROTOCOL NUMBERS
   Table:
      ftp://ftp.isi.edu/in-notes/iana/assignments/protocol-numbers"
::= {
      ether2 0x0800,
      llc 0x06,
      snap 0x0800,
      ip 4,
      ip 94
}

IPX

ipx PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
     hasChildren(0),
     addressRecognitionCapable(1)
}
DESCRIPTION
   "Novell IPX"
CHILDREN
   "Children of IPX are defined by the 16 bit value of the
   Destination Socket field.  The value is encoded into an octet
   string as [ 0.0.a.b ], where 'a' and 'b' are the network byte
   order encodings of the MSB and LSB of the destination socket
   field."
ADDRESS-FORMAT
   "4 bytes of Network number followed by the 6 bytes Host address
   each in network byte order".
REFERENCE
   "The IPX protocol is defined by the Novell Corporation
   A complete description of IPX may be secured at the following
   address:
          Novell, Inc.
          122 East 1700 South
          P. O. Box 5900
          Provo, Utah 84601 USA
          800 526 5463
          Novell Part # 883-000780-001"
::= {
    ether2     0x8137,           -- 0.0.129.55
    llc        0xe0e003,         -- 0.224.224.3
    snap       0x8137,           -- 0.0.129.55
    ianaAssigned 0x1               -- 0.0.0.1   (ipxOverRaw8023)
}

ARP

arp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "An Address Resolution Protocol message (request or response).
   This protocol does not include Reverse ARP (RARP) packets, which
   are counted separately."
REFERENCE
   "RFC 826 RFC826 defines the Address Resolution Protocol."
::= {
    ether2 0x806,   -- [ 0.0.8.6 ]
    snap 0x806
}

IDP

idp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
     hasChildren(0),
     addressRecognitionCapable(1)
}
DESCRIPTION
   "Xerox IDP"
CHILDREN
   "Children of IDP are defined by the 8 bit value of the Packet
   type field.  The value is encoded into an octet string as [
   0.0.0.a ], where 'a' is the value of the packet type field in
   network byte order."
ADDRESS-FORMAT
   "4 bytes of Network number followed by the 6 bytes Host address
   each in network byte order".
REFERENCE
   "Xerox Corporation, Document XNSS 028112, 1981"
::=  {
   ether2  0x600,     -- [ 0.0.6.0 ]
   snap    0x600
}

AppleTalk ARP

atalkarp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "AppleTalk Address Resolution Protocol."
REFERENCE
   "AppleTalk Phase 2 Protocol Specification, document ADPA
   #C0144LL/A."
::=   {
  ether2 0x80f3,  --  [ 0.0.128.243 ]
  vsnap(0x080007) 0x80f3
}

AppleTalk

atalk PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
    hasChildren(0),
    addressRecognitionCapable(1)
}
DESCRIPTION
   "AppleTalk Protocol."
CHILDREN
   "Children of ATALK are defined by the 8 bit value of the DDP type
   field.  The value is encoded into an octet string as [ 0.0.0.a ],
   where 'a' is the value of the DDP type field in network byte
   order."
ADDRESS-FORMAT
   "2 bytes of Network number followed by 1 byte of node id each in
   network byte order".
REFERENCE
   "AppleTalk Phase 2 Protocol Specification, document ADPA
   #C0144LL/A."
::=   {
  ether2  0x809b,   -- [ 0.0.128.155 ]
  vsnap(0x080007) 0x809b
}

L4: Children of L3 Protocols

ICMP

icmp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Internet Message Control Protocol."
REFERENCE
   "RFC 792 RFC792 defines the Internet Control Message Protocol."
::= { ip 1 }

TCP

tcp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
     hasChildren(0)
}
DESCRIPTION
   "Transmission Control Protocol."
CHILDREN
   "Children of TCP are identified by the 16 bit Destination Port
   value as specified in RFC 793. They are encoded as [ 0.0.a.b],
   where 'a' is the MSB and 'b' is the LSB of the Destination Port
   value. Both bytes are encoded in network byte order.  For
   example, a protocolDirId-fragment of:
       0.0.0.1.0.0.8.0.0.0.0.6.0.0.0.23
   identifies an encapsulation of the telnet protocol
   (ether2.ip.tcp.telnet)"
REFERENCE
   "RFC 793 RFC793 defines the Transmission Control Protocol.
   The following URL defines the authoritative repository for
   reserved and registered TCP port values:
     ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers"
::=  { ip 6 }

UDP

udp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
     hasChildren(0)
}
DESCRIPTION
   "User Datagram Protocol."
CHILDREN
   "Children of UDP are identified by the 16 bit Destination Port
   value as specified in RFC 768. They are encoded as [ 0.0.a.b ],
   where 'a' is the MSB and 'b' is the LSB of the Destination Port
   value. Both bytes are encoded in network byte order.  For
   example, a protocolDirId-fragment of:
       0.0.0.1.0.0.8.0.0.0.0.17.0.0.0.161
   identifies an encapsulation of SNMP (ether2.ip.udp.snmp)"
REFERENCE
   "RFC 768 RFC768 defines the User Datagram Protocol.
   The following URL defines the authoritative repository for
   reserved and registered UDP port values:
     ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers"
= { ip 17 }

L5: Application Layer Protocols

FTP

FTP-DATA

ftp-data PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "The File Transfer Protocol Data Port; the FTP Server process
   default data-connection port. "
REFERENCE
   "RFC 959 RFC959 defines the File Transfer Protocol.  Refer to
   section 3.2 of RFC959 for details on FTP data connections."
::= { tcp 20 }
FTP Control

ftp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "The File Transfer Protocol Control Port; An FTP client initiates
   an FTP control connection by sending FTP commands from user port
   (U) to this port."
REFERENCE
   "RFC 959 RFC959 defines the File Transfer Protocol."
::= { tcp 21 }

Telnet

telnet PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "The Telnet Protocol; The purpose of the TELNET Protocol is to
   provide a fairly general, bi-directional, eight-bit byte oriented
   communications facility.  Its primary goal is to allow a standard
   method of interfacing terminal devices and terminal-oriented
   processes to each other. "
REFERENCE
   "RFC 854 RFC854 defines the basic Telnet Protocol."
::= { tcp 23 }

SMTP

smtp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "The Simple Mail Transfer Protocol; SMTP control and data
   messages are sent on this port."
REFERENCE
   "RFC 821 RFC821 defines the basic Simple Mail Transfer
   Protocol."
::= { tcp 25 }

DNS

domain PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Domain Name Service Protocol; DNS may be transported by either
   UDP RFC768 or TCP RFC793.  If the transport is UDP, DNS
   requests restricted to 512 bytes in length may be sent to this
   port."
REFERENCE
   "RFC 1035 RFC1035 defines the Bootstrap Protocol."
::= { udp 53,
      tcp 53  }

BOOTP

Bootstrap Server Protocol

bootps PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Bootstrap Protocol Server Protocol; BOOTP Clients send requests
   (usually broadcast) to the bootps port."
REFERENCE
   "RFC 951 RFC951 defines the Bootstrap Protocol."
::= { udp 67 }
Bootstrap Client Protocol

bootpc PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Bootstrap Protocol Client Protocol; BOOTP Server replies are
   sent to the BOOTP Client using this destination port."
REFERENCE
   "RFC 951 RFC951 defines the Bootstrap Protocol."
::= { udp 68 }

TFTP

tftp PROTOCOL-IDENTIFIER

PARAMETERS {
    tracksSessions(1)
}
ATTRIBUTES { }
DESCRIPTION
   "Trivial File Transfer Protocol; Only the first packet of each
   TFTP transaction will be sent to port 69. If the tracksSessions
   attribute is set, then packets for each TFTP transaction will be
   attributed to tftp, instead of the unregistered port numbers that
   will be encoded in subsequent packets."
REFERENCE
   "RFC 1350 RFC1350 defines the TFTP Protocol (revision 2); RFC
   1782 RFC1782 defines TFTP Option Extensions; RFC 1783 RFC1783
   defines the TFTP Blocksize Option; RFC 1784 RFC1784 defines
   TFTP Timeout Interval and Transfer Size Options."
::= { udp 69 }

HTTP

www-http PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Hypertext Transfer Protocol; "
REFERENCE
   "RFC 1945 RFC1945 defines the Hypertext Transfer Protocol
   (HTTP/1.0)."
::= { tcp 80 }

POP3

pop3 PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Post Office Protocol -- Version 3. Clients establish connections
   with POP3 servers by using this destination port number."
REFERENCE
   "RFC 1725 RFC1725 defines Version 3 of the Post Office
   Protocol."
::= { tcp 110 }

SUNRPC

sunrpc PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES {
            hasChildren(0)   -- port mapper function numbers
    }
DESCRIPTION
   "SUN Remote Procedure Call Protocol. Port mapper function
   requests are sent to this destination port."
CHILDREN
   Specific RPC functions are represented as children of the sunrpc
   protocol. Each 'RPC function protocol' is identified by its
   function number assignment. RPC function number assignments are
   defined by different naming authorities, depending of the
   function identifier value.
   From RFC1831:
   Program numbers are given out in groups of hexadecimal 20000000
   (decimal 536870912) according to the following chart:
                 0 - 1fffffff   defined by [email protected]
          20000000 - 3fffffff   defined by user
          40000000 - 5fffffff   transient
          60000000 - 7fffffff   reserved
          80000000 - 9fffffff   reserved
          a0000000 - bfffffff   reserved
          c0000000 - dfffffff   reserved
          e0000000 - ffffffff   reserved
   Children of 'sunrpc' are encoded as [ 0.0.0.111], the protocol
   identifier component for 'sunrpc', followed by [ a.b.c.d ], where
   a.b.c.d is the 32 bit binary RPC program number encoded in
   network byte order.  For example, a protocolDirID-fragment value
   of:
       0.0.0.111.0.1.134.163
   defines the NFS function (and protocol).
   Children are named as 'sunrpc' followed by the RPC function
   number in base 10 format. For example, NFS would be named:
       'sunrpc 100003'.
REFERENCE
   "RFC 1831 RFC1831 defines the Remote Procedure Call Protocol
   Version 2.  The authoritative list of RPC Functions is identified
   by the URL:
       ftp://ftp.isi.edu/in-notes/iana/assignments/sun-rpc-numbers"
::= { udp 111 }

5.5.10. NFS

nfs PROTOCOL-IDENTIFIER

PARAMETERS {
            countsFragments(0)
    }
ATTRIBUTES { }
DESCRIPTION
   "Sun Network File System (NFS);"
DECODING
   "The first packet in an NFS transaction is sent to the port-
   mapper, and therefore decoded statically by monitoring RFC
   portmap requests RFC1831. Any subsequent NFS fragments must be
   decoded and correctly identified by 'remembering' the port
   assignments used in each RPC function call (as identified
   according to the procedures in the RPC Specification Version 2
   RFC1831).
   The 'countsFragments(0)' PARAMETER bit is used to indicate
   whether the probe can (and should) monitor portmapper activity to
   correctly attribute all NFS packets."
REFERENCE
   "The NFS Version 3 Protocol Specification is defined in RFC 1813
   RFC1813."
::= {
    sunrpc 100003           --  [0.1.134.163]
}

5.5.11. SNMP

5.5.11.1. SNMP Request/Response

snmp PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Simple Network Management Protocol. Includes SNMPv1 and SNMPv2
   protocol versions. Does not include SNMP trap packets."
REFERENCE
   "The SNMP SMI is defined in RFC 1902 RFC1902. The SNMP
   protocol is defined in RFC 1905 RFC1905.  Transport mappings
   are defined in RFC 1906 RFC1906; RFC 1420 (SNMP over IPX)
   RFC1420; RFC 1419 (SNMP over AppleTalk) RFC1419."
::= {
    udp 161,
    ipx 0x900f,   -- [ 0.0.144.15 ]
    atalk 8
}

5.5.11.2. SNMP Trap

snmptrap PROTOCOL-IDENTIFIER

PARAMETERS { }
ATTRIBUTES { }
DESCRIPTION
   "Simple Network Management Protocol Trap Port."
REFERENCE
   "The SNMP SMI is defined in RFC 1902 RFC1902. The SNMP
   protocol is defined in RFC 1905 RFC1905.  Transport mappings
   are defined in RFC 1906 RFC1906; RFC 1420 (SNMP over IPX)
   RFC1420; RFC 1419 (SNMP over AppleTalk) RFC1419."
::= {
    udp 162,
    ipx 0x9010,
    atalk 9
}

Acknowledgements

This document was produced by the IETF RMONMIB Working Group.

The authors wish to thank the following people for their contributions to this document:

    Anil Singhal
    Frontier Software Development, Inc.
    Jeanne Haney
    Bay Networks
    Dan Hansen
    Network General Corp.

References

RFC768

 Postel, J., "User Datagram Protocol", STD 6, RFC 768,
 USC/Information Sciences Institute, August 1980.

RFC791

 Postel, J., ed., "Internet Protocol - DARPA Internet Program
 Protocol Specification", STD 5, RFC 791, USC/Information Sciences
 Institute, September 1981.

RFC792

 Postel, J., "Internet Control Message Protocol - DARPA Internet
 Program Protocol Specification", STD 5, RFC 792, USC/Information
 Sciences Institute, September 1981.

RFC793

 Postel, J., "Transmission Control Protocol - DARPA Internet Program
 Protocol Specification", STD 5, RFC 793, USC/Information Sciences
 Institute, September 1981.

RFC821

 Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC 821,
 USC/Information Sciences Institute, August 1982.

RFC826

 Plummer, D., "An Ethernet Address Resolution Protocol or
 "Converting Network Protocol Addresses to 48-bit Ethernet Addresses
 for Transmission on Ethernet Hardware", STD 37, RFC 826, MIT-LCS,
 November 1982.

RFC854

 Postel, J. and J. Reynolds, "Telnet Protocol Specification",
 STD 8, RFC 854, ISI, May 1983.

RFC894

 Hornig, C., "A Standard for the Transmission of IP Datagrams over
 Ethernet Networks", RFC 894, Symbolics, April 1984.

RFC951

 Croft, B., and J. Gilmore, "BOOTSTRAP Protocol (BOOTP)", RFC 951,
 Stanford and SUN Microsytems, September 1985.

RFC959

 Postel, J., and J. Reynolds, "File Transfer Protocol", STD 8,
 RFC 959, USC/Information Sciences Institute, October 1985.

RFC1035

 Mockapetris, P., "Domain Names - Implementation and Specification",
 STD 13, RFC 1035, USC/Information Sciences Institute, November
 1987.

RFC1157

 Case, J., M. Fedor, M. Schoffstall, J. Davin, "Simple Network
 Management Protocol", STD 15, RFC 1157, SNMP Research,
 Performance Systems International, MIT Laboratory for Computer
 Science, May 1990.

RFC1213

 McCloghrie, K., and M. Rose, Editors, "Management Information Base
 for Network Management of TCP/IP-based internets: MIB-II", STD 17,
 RFC 1213, Hughes LAN Systems, Performance Systems International,
 March 1991.

RFC1350

 Sollins, K., "TFTP Protocol (revision 2)", RFC 1350, MIT, July
 1992.

RFC1419

 Minshall, G., and M.  Ritter, "SNMP over AppleTalk", RFC 1419,
 Novell, Inc., Apple Computer, Inc., March 1993.

RFC1420

 Bostock, S., "SNMP over IPX", RFC 1420, Novell, Inc., March 1993.

RFC1700

 Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC 1700,
 USC/Information Sciences Institute, October 1994.

RFC1725

 Myers, J., and M. Rose, "Post Office Protocol - Version 3", RFC
 1725, Carnegie Mellon, Dover Beach Consulting, November 1994.

RFC1757

 S. Waldbusser, "Remote Network Monitoring MIB", RFC 1757, Carnegie
 Mellon University, February 1995.

RFC1782

 Malkin, G., and A. Harkin, T "TFTP Option Extension", RFC 1782,
 Xylogics, Inc., Hewlett Packard Co., March 1995.

RFC1783

 Malkin, G., and A. Harkin, T "TFTP BlockOption Option", RFC 1783,
 Xylogics, Inc., Hewlett Packard Co., March 1995.

RFC1784

 Malkin, G., and A. Harkin, "TFTP Timeout Interval and Transfer Size
 Options", RFC 1784, Xylogics, Inc., Hewlett Packard Co., March
 1995.

RFC1800

 Postel, J., Editor, "Internet Official Protocol Standards", STD 1,
 RFC 1920, IAB, March 1996.

RFC1831

 Srinivasan, R., "Remote Procedure Call Protocol Version 2", RFC
 1831, Sun Microsystems, Inc., August 1995.

RFC1902

 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
 S. Waldbusser, "Structure of Management Information for version 2
 of the Simple Network Management Protocol (SNMPv2)", RFC 1902,
 January 1996.

RFC1903

 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
 S. Waldbusser, "Textual Conventions for version 2 of the Simple
 Network Management Protocol (SNMPv2)", RFC 1903, January 1996.

RFC1904

 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
 S. Waldbusser, "Conformance Statements for version 2 of the Simple
 Network Management Protocol (SNMPv2)", RFC 1904, January 1996.

RFC1905

 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
 S. Waldbusser, "Protocol Operations for version 2 of the Simple
 Network Management Protocol (SNMPv2)", RFC 1905, January 1996.

RFC1906

 SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and S.
 Waldbusser, "Transport Mappings for Version 2 of the Simple Network
 Management Protocol (SNMPv2)", RFC 1906, January 1996.

RFC1945

 Berners-Lee, T., and R. Fielding, "Hypertext Transfer Protocol --
 HTTP/1.0", RFC 1945, MIT/UC-Irvine, November 1995.

[RMON2]

 S. Waldbusser, "Remote Network Monitoring MIB (RMON-2)", draft-
 ietf-rmonmib-rmon2-03.txt, International Network Services, January
 1996.

Security Considerations

Security issues are not discussed in this memo.

Authors' Addresses

Andy Bierman Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134

Phone: 408-527-3711 EMail: [email protected]

Robin Iddon 3Com/AXON 40/50 Blackfrias Street Edinburgh, UK

Phone: +44 131.558.3888 EMail: [email protected]