IPv6 MIB Design Team M. Daniele
Internet-Draft Consultant
Expires: July 2, 2004 B. Haberman
Caspian Networks
S. Routhier
Wind River Systems, Inc.
J. Schoenwaelder
International University Bremen
January 2, 2004
Textual Conventions for Internet Network Addresses
draft-ietf-ops-rfc3291bis-03.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at http://
www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
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This Internet-Draft will expire on July 2, 2004.
Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
This MIB module defines textual conventions to represent commonly
used Internet network layer addressing information. The intent is
that these textual conventions will be imported and used in MIB
modules that would otherwise define their own representations.
This document obsoletes RFC 3291.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. The Internet-Standard Management Framework . . . . . . . . . . 5
3. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Usage Hints . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.1 Table Indexing . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2 Uniqueness of Addresses . . . . . . . . . . . . . . . . . . . 14
4.3 Multiple Addresses per Host . . . . . . . . . . . . . . . . . 15
4.4 Resolving DNS Names . . . . . . . . . . . . . . . . . . . . . 15
5. Table Indexing Example . . . . . . . . . . . . . . . . . . . . 16
6. Security Considerations . . . . . . . . . . . . . . . . . . . 18
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18
8. Intellectual Property Notice . . . . . . . . . . . . . . . . . 18
9. Changes from RFC 3291 . . . . . . . . . . . . . . . . . . . . 18
10. Changes from RFC 2851 . . . . . . . . . . . . . . . . . . . . 19
Normative References . . . . . . . . . . . . . . . . . . . . . 19
Informative References . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 20
Intellectual Property and Copyright Statements . . . . . . . . 22
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1. Introduction
Several standard-track MIB modules use the IpAddress SMIv2 base type.
This limits the applicability of these MIB modules to IP Version 4
(IPv4) since the IpAddress SMIv2 base type can only contain 4 byte
IPv4 addresses. The IpAddress SMIv2 base type has become problematic
with the introduction of IP Version 6 (IPv6) addresses [RFC3513].
This document defines multiple textual conventions (TCs) as a
mechanism to express generic Internet network layer addresses within
MIB module specifications. The solution is compatible with SMIv2 (STD
58) and SMIv1 (STD 16). New MIB definitions which need to express
network layer Internet addresses SHOULD use the textual conventions
defined in this memo. New MIB modules SHOULD NOT use the SMIv2
IpAddress base type anymore.
A generic Internet address consists of two objects, one whose syntax
is InetAddressType, and another whose syntax is InetAddress. The
value of the first object determines how the value of the second
object is encoded. The InetAddress textual convention represents an
opaque Internet address value. The InetAddressType enumeration is
used to "cast" the InetAddress value into a concrete textual
convention for the address type. This usage of multiple textual
conventions allows expression of the display characteristics of each
address type and makes the set of defined Internet address types
extensible.
The textual conventions for well-known transport domains support
scoped Internet addresses. The scope of an Internet address is a
topological span within which the address may be used as a unique
identifier for an interface or set of interfaces. A scope zone, or
simply a zone, is a concrete connected region of topology of a given
scope. Note that a zone is a particular instance of a topological
region, whereas a scope is the size of a topological region
[RFCZZZZ]. Since Internet addresses on devices that connect multiple
zones are not necessarily unique, an additional zone index is needed
on these devices to select an interface. The textual conventions
InetAddressIPv4z and InetAddressIPv6z are provided to support
Internet addresses that include a zone index. In order to support
arbitrary combinations of scoped Internet addresses, MIB authors
SHOULD use a separate InetAddressType object for each InetAddress
object.
The textual conventions defined in this document can also be used to
represent generic Internet subnets and Internet address ranges. A
generic Internet subnet is represented by three objects, one whose
syntax is InetAddressType, a second one whose syntax is InetAddress
and a third one whose syntax is InetAddressPrefixLength. The
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InetAddressType value again determines the concrete format of the
InetAddress value while the InetAddressPrefixLength identifies the
Internet network address prefix.
A generic range of consecutive Internet addresses is represented by
three objects. The first one has the syntax InetAddressType while the
remaining objects have the syntax InetAddress and specify the start
and end of the address range. The InetAddressType value again
determines the format of the InetAddress values.
The textual conventions defined in this document can be used to
define Internet addresses by using DNS domain names in addition to
IPv4 and IPv6 addresses. A MIB designer can write compliance
statements to express that only a subset of the possible address
types must be supported by a compliant implementation.
MIB developers who need to represent Internet addresses SHOULD use
these definitions whenever applicable, as opposed to defining their
own constructs. Even MIB modules that only need to represent IPv4 or
IPv6 addresses SHOULD use the InetAddressType/InetAddress textual
conventions defined in this memo.
There are many widely deployed MIB modules that use IPv4 addresses
and which need to be revised to support IPv6. These MIBs can be
categorized as follows:
1. MIB modules which define management information that is in
principle IP version neutral, but the MIB currently uses
addressing constructs specific to a certain IP version.
2. MIB modules which define management information that is specific
to particular IP version (either IPv4 or IPv6) and which is very
unlikely to ever be applicable to another IP version.
MIB modules of the first type SHOULD provide object definitions
(e.g., tables) that work with all versions of IP. In particular, when
revising a MIB module which contains IPv4 specific tables, it is
suggested to define new tables using the textual conventions defined
in this memo which support all versions of IP. The status of the new
tables SHOULD be "current" while the status of the old IP version
specific tables SHOULD be changed to "deprecated". The other approach
of having multiple similar tables for different IP versions is
strongly discouraged.
MIB modules of the second type, which are inherently IP version
specific, do not need to be redefined. Note that even in this case,
any additions to these MIB modules or new IP version specific MIB
modules SHOULD use the textual conventions defined in this memo.
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MIB developers SHOULD NOT use the textual conventions defined in this
document to represent generic transport layer addresses. Instead the
SMIv2 TAddress textual convention and associated definitions should
be used for transport layer addresses.
The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT" and "MAY" in
this document are to be interpreted as described in RFC 2119
[RFC2119].
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
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. Definitions
INET-ADDRESS-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, mib-2, Unsigned32 FROM SNMPv2-SMI
TEXTUAL-CONVENTION FROM SNMPv2-TC;
inetAddressMIB MODULE-IDENTITY
LAST-UPDATED "200401020000Z"
ORGANIZATION
"IETF Operations and Management Area"
CONTACT-INFO
"Juergen Schoenwaelder (Editor)
International University Bremen
P.O. Box 750 561
28725 Bremen, Germany
Phone: +49 421 200-3587
EMail: j.schoenwaelder@iu-bremen.de
Send comments to <mibs@ops.ietf.org>."
DESCRIPTION
"This MIB module defines textual conventions for
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representing Internet addresses. An Internet
address can be an IPv4 address, an IPv6 address
or a DNS domain name. This module also defines
textual conventions for Internet port numbers,
autonomous system numbers and the length of an
Internet address prefix.
Copyright (C) The Internet Society (2003). This version
of this MIB module is part of RFC XXXX, see the RFC
itself for full legal notices."
REVISION "200401020000Z"
DESCRIPTION
"Third version, published as RFC XXXX. This revision
introduces the InetZoneIndex, InetScopeType and
InetVersion textual conventions."
REVISION "200205090000Z"
DESCRIPTION
"Second version, published as RFC 3291. This
revisions contains several clarifications and it
introduces several new textual conventions:
InetAddressPrefixLength, InetPortNumber,
InetAutonomousSystemNumber, InetAddressIPv4z,
and InetAddressIPv6z."
REVISION "200006080000Z"
DESCRIPTION
"Initial version, published as RFC 2851."
::= { mib-2 76 }
InetAddressType ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"A value that represents a type of Internet address.
unknown(0) An unknown address type. This value MUST
be used if the value of the corresponding
InetAddress object is a zero-length string.
It may also be used to indicate an IP address
which is not in one of the formats defined
below.
ipv4(1) An IPv4 address as defined by the
InetAddressIPv4 textual convention.
ipv6(2) An IPv6 address as defined by the
InetAddressIPv6 textual convention.
ipv4z(3) A non-global IPv4 address including a zone
index as defined by the InetAddressIPv4z
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textual convention.
ipv6z(4) A non-global IPv6 address including a zone
index as defined by the InetAddressIPv6z
textual convention.
dns(16) A DNS domain name as defined by the
InetAddressDNS textual convention.
Each definition of a concrete InetAddressType value must be
accompanied by a definition of a textual convention for use
with that InetAddressType.
To support future extensions, the InetAddressType textual
convention SHOULD NOT be sub-typed in object type definitions.
It MAY be sub-typed in compliance statements in order to
require only a subset of these address types for a compliant
implementation.
Implementations must ensure that InetAddressType objects
and any dependent objects (e.g. InetAddress objects) are
consistent. An inconsistentValue error must be generated
if an attempt to change an InetAddressType object would,
for example, lead to an undefined InetAddress value. In
particular, InetAddressType/InetAddress pairs must be
changed together if the address type changes (e.g. from
ipv6(2) to ipv4(1))."
SYNTAX INTEGER {
unknown(0),
ipv4(1),
ipv6(2),
ipv4z(3),
ipv6z(4),
dns(16)
}
InetAddress ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"Denotes a generic Internet address.
An InetAddress value is always interpreted within the context
of an InetAddressType value. Every usage of the InetAddress
textual convention is required to specify the InetAddressType
object which provides the context. It is suggested that the
InetAddressType object is logically registered before the
object(s) which use the InetAddress textual convention if
they appear in the same logical row.
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The value of an InetAddress object must always be
consistent with the value of the associated InetAddressType
object. Attempts to set an InetAddress object to a value
which is inconsistent with the associated InetAddressType
must fail with an inconsistentValue error.
When this textual convention is used as the syntax of an
index object, there may be issues with the limit of 128
sub-identifiers specified in SMIv2, STD 58. In this case,
the object definition MUST include a 'SIZE' clause to
limit the number of potential instance sub-identifiers
or else the applicable constraints MUST be stated in
the appropriate conceptual row DESCRIPTION clauses or
in the surrounding documentation if there is no single
DESCRIPTION clause that is appropriate."
SYNTAX OCTET STRING (SIZE (0..255))
InetAddressIPv4 ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1d.1d.1d.1d"
STATUS current
DESCRIPTION
"Represents an IPv4 network address:
octets contents encoding
1-4 IPv4 address network-byte order
The corresponding InetAddressType value is ipv4(1).
This textual convention SHOULD NOT be used directly in object
definitions since it restricts addresses to a specific format.
However, if it is used, it MAY be used either on its own or in
conjunction with InetAddressType as a pair."
SYNTAX OCTET STRING (SIZE (4))
InetAddressIPv6 ::= TEXTUAL-CONVENTION
DISPLAY-HINT "2x:2x:2x:2x:2x:2x:2x:2x"
STATUS current
DESCRIPTION
"Represents an IPv6 network address:
octets contents encoding
1-16 IPv6 address network-byte order
The corresponding InetAddressType value is ipv6(2).
This textual convention SHOULD NOT be used directly in object
definitions since it restricts addresses to a specific format.
However, if it is used, it MAY be used either on its own or in
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conjunction with InetAddressType as a pair."
SYNTAX OCTET STRING (SIZE (16))
InetAddressIPv4z ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1d.1d.1d.1d%4d"
STATUS current
DESCRIPTION
"Represents a non-global IPv4 network address together
with its zone index:
octets contents encoding
1-4 IPv4 address network-byte order
5-8 zone index network-byte order
The corresponding InetAddressType value is ipv4z(3).
The zone index (bytes 5-8) is used to disambiguate identical
address values on nodes which have interfaces attached to
different zones of the same scope. The zone index may contain
the special value 0 which refers to the default zone for each
scope.
This textual convention SHOULD NOT be used directly in object
definitions since it restricts addresses to a specific format.
However, if it is used, it MAY be used either on its own or in
conjunction with InetAddressType as a pair."
SYNTAX OCTET STRING (SIZE (8))
InetAddressIPv6z ::= TEXTUAL-CONVENTION
DISPLAY-HINT "2x:2x:2x:2x:2x:2x:2x:2x%4d"
STATUS current
DESCRIPTION
"Represents a non-global IPv6 network address together
with its zone index:
octets contents encoding
1-16 IPv6 address network-byte order
17-20 zone index network-byte order
The corresponding InetAddressType value is ipv6z(4).
The zone index (bytes 17-20) is used to disambiguate
identical address values on nodes which have interfaces
attached to different zones of the same scope. The zone index
may contain the special value 0 which refers to the default
zone for each scope.
This textual convention SHOULD NOT be used directly in object
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definitions since it restricts addresses to a specific format.
However, if it is used, it MAY be used either on its own or in
conjunction with InetAddressType as a pair."
SYNTAX OCTET STRING (SIZE (20))
InetAddressDNS ::= TEXTUAL-CONVENTION
DISPLAY-HINT "255a"
STATUS current
DESCRIPTION
"Represents a DNS domain name. The name SHOULD be fully
qualified whenever possible.
The corresponding InetAddressType is dns(16).
The DESCRIPTION clause of InetAddress objects that may have
InetAddressDNS values must fully describe how (and when) such
names are to be resolved to IP addresses.
This textual convention SHOULD NOT be used directly in object
definitions since it restricts addresses to a specific format.
However, if it is used, it MAY be used either on its own or in
conjunction with InetAddressType as a pair."
SYNTAX OCTET STRING (SIZE (1..255))
InetAddressPrefixLength ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"Denotes the length of a generic Internet network address
prefix. A value of n corresponds to an IP address mask
which has n contiguous 1-bits from the most significant
bit (MSB) and all other bits set to 0.
An InetAddressPrefixLength value is always interpreted within
the context of an InetAddressType value. Every usage of the
InetAddressPrefixLength textual convention is required to
specify the InetAddressType object which provides the
context. It is suggested that the InetAddressType object is
logically registered before the object(s) which use the
InetAddressPrefixLength textual convention if they appear in
the same logical row.
InetAddressPrefixLength values that are larger than
the maximum length of an IP address for a specific
InetAddressType are treated as the maximum significant
value applicable for the InetAddressType. The maximum
significant value is 32 for the InetAddressType
'ipv4(1)' and 'ipv4z(3)' and 128 for the InetAddressType
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'ipv6(2)' and 'ipv6z(4)'. The maximum significant value
for the InetAddressType 'dns(16)' is 0.
The value zero is object-specific and must be defined as
part of the description of any object which uses this
syntax. Examples of the usage of zero might include
situations where the Internet network address prefix
is unknown or does not apply."
SYNTAX Unsigned32
InetPortNumber ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"Represents a 16 bit port number of an Internet transport
layer protocol. Port numbers are assigned by IANA. A
current list of all assignments is available from
<http://www.iana.org/>.
The value zero is object-specific and must be defined as
part of the description of any object which uses this
syntax. Examples of the usage of zero might include
situations where a port number is unknown, or when the
value zero is used as a wildcard in a filter."
REFERENCE "STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960"
SYNTAX Unsigned32 (0..65535)
InetAutonomousSystemNumber ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"Represents an autonomous system number which identifies an
Autonomous System (AS). An AS is a set of routers under a
single technical administration, using an interior gateway
protocol and common metrics to route packets within the AS,
and using an exterior gateway protocol to route packets to
other ASs'. IANA maintains the AS number space and has
delegated large parts to the regional registries.
Autonomous system numbers are currently limited to 16 bits
(0..65535). There is however work in progress to enlarge the
autonomous system number space to 32 bits. This textual
convention therefore uses an Unsigned32 value without a
range restriction in order to support a larger autonomous
system number space."
REFERENCE "RFC 1771, RFC 1930"
SYNTAX Unsigned32
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InetScopeType ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"Represents a scope type. This textual convention can be used
in cases where a MIB has to represent different scope types
and there is no context information such as an InetAddress
object which implicitely defines the scope type.
Note that not all possible values have been assigned yet but
they may be assigned in future revisions of this specification.
Applications should therefore be able to deal with not yet
assigned values."
REFERENCE "RFC 3513"
SYNTAX INTEGER {
-- reserved(0),
interfaceLocal(1),
linkLocal(2),
subnetLocal(3),
adminLocal(4),
siteLocal(5),
-- unassigned(6),
-- unassigned(7),
organizationLocal(8),
-- unassigned(9),
-- unassigned(10),
-- unassigned(11),
-- unassigned(12),
-- unassigned(13),
global(14)
-- reserved(15)
}
InetZoneIndex ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"A zone index identifies an instance of a zone of a
specific scope.
The zone index MUST disambiguate identical address
values. For link-local addresses, the zone index will
typically be the interface index (ifIndex as defined in the
IF-MIB) of the interface on which the address is configured.
The zone index may contain the special value 0 which refers
to the default zone. The default zone may be used in cases
where the valid zone index is not known (e.g., a management
application needs to write a site-local IPv6 address without
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knowing the site index value). The default zone SHOULD NOT be
used as an easy way out in cases where the zone index for a
non-global IPv6 address is known."
REFERENCE "RFCZZZZ"
SYNTAX Unsigned32
InetVersion ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"A value representing a version of the IP protocol.
unknown(0) An unknown or unspecified version of the IP
protocol.
ipv4(1) The IPv4 protocol as defined in RFC 791 (STD 5).
ipv6(2) The IPv6 protocol as defined in RFC 2460.
Note that this textual convention SHOULD NOT be used to
distinguish different address types associated with IP
protocols. The InetAddressType has been designed for this
purpose."
REFERENCE "RFC 791, RFC 2460"
SYNTAX INTEGER {
unknown(0),
ipv4(1),
ipv6(2)
}
END
4. Usage Hints
The InetAddressType and InetAddress textual conventions have been
introduced to avoid over-constraining an object definition by the use
of the IpAddress SMI base type which is IPv4 specific. An
InetAddressType/InetAddress pair can represent IP addresses in
various formats.
The InetAddressType and InetAddress objects SHOULD NOT be sub-typed
in object definitions. Sub-typing binds the MIB module to specific
address formats, which may cause serious problems if new address
formats need to be introduced. Note that it is possible to write
compliance statements in order to express that only a subset of the
defined address types must be implemented to be compliant.
Every usage of the InetAddress or InetAddressPrefixLength textual
conventions must specify which InetAddressType object provides the
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context for the interpretation of the InetAddress or
InetAddressPrefixLength textual convention.
It is suggested that the InetAddressType object is logically
registered before the object(s) which uses the InetAddress or
InetAddressPrefixLength textual convention. An InetAddressType object
is logically registered before an InetAddress or
InetAddressPrefixLength object if it appears before the InetAddress
or InetAddressPrefixLength object in the conceptual row (which
includes any index objects). This rule allows programs such as MIB
compilers to identify the InetAddressType of a given InetAddress or
InetAddressPrefixLength object by searching for the InetAddressType
object which precedes an InetAddress or InetAddressPrefixLength
object.
4.1 Table Indexing
When a generic Internet address is used as an index, both the
InetAddressType and InetAddress objects MUST be used. The
InetAddressType object MUST be listed before the InetAddress object
in the INDEX clause.
The IMPLIED keyword MUST NOT be used for an object of type
InetAddress in an INDEX clause. Instance sub-identifiers are then of
the form T.N.O1.O2...On, where T is the value of the InetAddressType
object, O1...On are the octets in the InetAddress object, and N is
the number of those octets.
There is a meaningful lexicographical ordering to tables indexed in
this fashion. Command generator applications may lookup specific
addresses of known type and value, issue GetNext requests for
addresses of a single type, or issue GetNext requests for a specific
type and address prefix.
4.2 Uniqueness of Addresses
IPv4 addresses were intended to be globally unique, current usage
notwithstanding. IPv6 addresses were architected to have different
scopes and hence uniqueness [RFC3513]. In particular, IPv6
"link-local" unicast addresses are not guaranteed to be unique on any
particular node. In such cases, the duplicate addresses must be
configured on different interfaces. So the combination of an IPv6
address and a zone index is unique [RFCZZZZ].
The InetAddressIPv6 textual convention has been defined to represent
global IPv6 addresses and non-global IPv6 addresses in cases where no
zone index is needed (e.g., on end hosts with a single interface).
The InetAddressIPv6z textual convention has been defined to represent
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non-global IPv6 addresses in cases where a zone index is needed
(e.g., a router connecting multiple zones). MIB designers who use
InetAddressType/InetAddress pairs therefore do not need to define
additional objects in order to support non-global addresses on nodes
that connect multiple zones.
The InetAddressIPv4z is intended for use in MIBs (like the TCP-MIB)
which report addresses in the address family used on the wire, but
where the entity instrumented obtains such addresses from
applications or administrators in a form which includes a zone index,
such as v4-mapped IPv6 addresses.
The size of the zone index has been chosen so that it is consistent
with (i) the numerical zone index defined in [RFCZZZZ] and (ii) the
sin6_scope_id field of the sockaddr_in6 structure defined in RFC 2553
[RFC2553].
4.3 Multiple Addresses per Host
A single host system may be configured with multiple addresses (IPv4
or IPv6), and possibly with multiple DNS names. Thus it is possible
for a single host system to be accessible by multiple
InetAddressType/InetAddress pairs.
If this could be an implementation or usage issue, the DESCRIPTION
clause of the relevant objects must fully describe which address is
reported in a given InetAddressType/InetAddress pair.
4.4 Resolving DNS Names
DNS names MUST be resolved to IP addresses when communication with
the named host is required. This raises a temporal aspect to defining
MIB objects whose value is a DNS name: When is the name translated to
an address?
For example, consider an object defined to indicate a forwarding
destination, and whose value is a DNS name. When does the forwarding
entity resolve the DNS name? Each time forwarding occurs or just once
when the object was instantiated?
The DESCRIPTION clause of such objects SHOULD precisely define how
and when any required name to address resolution is done.
Similarly, the DESCRIPTION clause of such objects SHOULD precisely
define how and when a reverse lookup is being done if an agent has
accessed instrumentation that knows about an IP address and the MIB
module or implementation requires it to map the IP address to a DNS
name.
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5. Table Indexing Example
This example shows a table listing communication peers that are
identified by either an IPv4 address, an IPv6 address or a DNS name.
The table definition also prohibits entries with an empty address
(whose type would be "unknown"). The size of a DNS name is limited to
64 characters in order to satisfy OID length constraints.
peerTable OBJECT-TYPE
SYNTAX SEQUENCE OF PeerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A list of communication peers."
::= { somewhere 1 }
peerEntry OBJECT-TYPE
SYNTAX PeerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry containing information about a particular peer."
INDEX { peerAddressType, peerAddress }
::= { peerTable 1 }
PeerEntry ::= SEQUENCE {
peerAddressType InetAddressType,
peerAddress InetAddress,
peerStatus INTEGER
}
peerAddressType OBJECT-TYPE
SYNTAX InetAddressType
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The type of Internet address by which the peer
is reachable."
::= { peerEntry 1 }
peerAddress OBJECT-TYPE
SYNTAX InetAddress (SIZE (1..64))
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Internet address for the peer. The type of this
address is determined by the value of the peerAddressType
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object. Note that implementations must limit themselves
to a single entry in this table per reachable peer.
The peerAddress may not be empty due to the SIZE
restriction.
If a row is created administratively by an SNMP
operation and the address type value is dns(16), then
the agent stores the DNS name internally. A DNS name
lookup must be performed on the internally stored DNS
name whenever it is being used to contact the peer.
If a row is created by the managed entity itself and
the address type value is dns(16), then the agent
stores the IP address internally. A DNS reverse lookup
must be performed on the internally stored IP address
whenever the value is retrieved via SNMP."
::= { peerEntry 2 }
The following compliance statement specifies that compliant
implementations need only support IPv4/IPv6 addresses without a zone
indices. Support for DNS names or IPv4/IPv6 addresses with zone
indices is not required.
peerCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement of the peer MIB."
MODULE -- this module
MANDATORY-GROUPS { peerGroup }
OBJECT peerAddressType
SYNTAX InetAddressType { ipv4(1), ipv6(2) }
DESCRIPTION
"An implementation is only required to support IPv4
and IPv6 addresses without zone indices."
::= { somewhere 2 }
Note that the SMIv2 does not permit inclusion of not-accessible
objects in an object group (see section 3.1 in STD 58, RFC 2580
[RFC2580]). It is therefore not possible to formally refine the
syntax of auxiliary objects which are not-accessible. In such a
case, it is suggested to express the refinement informally in the
DESCRIPTION clause of the MODULE-COMPLIANCE macro invocation.
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6. Security Considerations
This module does not define any management objects. Instead, it
defines a set of textual conventions which may be used by other MIB
modules to define management objects.
Meaningful security considerations can only be written in the MIB
modules that define management objects. This document has therefore
no impact on the security of the Internet.
7. Acknowledgments
This document was produced by the Operations and Management Area
"IPv6MIB" design team. The authors would like to thank Fred Baker,
Randy Bush, Richard Draves, Mark Ellison, Bill Fenner, Jun-ichiro
Hagino, Mike Heard, Tim Jenkins, Glenn Mansfield, Keith McCloghrie,
Thomas Narten, Erik Nordmark, Peder Chr. Norgaard, Randy Presuhn,
Andrew Smith, Dave Thaler, Kenneth White, Bert Wijnen, and Brian Zill
for their comments and suggestions.
8. Intellectual Property Notice
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP 11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
9. Changes from RFC 3291
The following changes have been made relative to RFC 3291:
o Added new textual conventions InetZoneIndex, InetScopeType and
InetVersion.
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o Added explicit "d" DISPLAY-HINTs for textual conventions that did
not have them.
o Updated boilerplate text and references.
10. Changes from RFC 2851
The following changes have been made relative to RFC 2851:
o Added new textual conventions InetAddressPrefixLength,
InetPortNumber, and InetAutonomousSystemNumber.
o Rewrote the introduction to say clearly that in general, one
should define MIB tables that work with all versions of IP. The
other approach of multiple tables for different IP versions is
strongly discouraged.
o Added text to the InetAddressType and InetAddress descriptions
which requires that implementations must reject set operations
with an inconsistentValue error if they lead to inconsistencies.
o Removed the strict ordering constraints. Description clauses now
must explain which InetAddressType object provides the context for
an InetAddress or InetAddressPrefixLength object.
o Aligned wordings with the IPv6 scoping architecture document.
o Split the InetAddressIPv6 textual convention into the two textual
conventions (InetAddressIPv6 and InetAddressIPv6z) and introduced
a new textual convention InetAddressIPv4z. Added ipv4z(3) and
ipv6z(4) named numbers to the InetAddressType enumeration.
Motivations for this change: (i) enable the introduction of a
textual conventions for non-global IPv4 addresses, (ii) alignment
with the textual conventions for transport addresses, (iii)
simpler compliance statements in cases where support for IPv6
addresses with zone indices is not required, (iv) simplify
implementations for host systems which will never have to report
zone indices.
Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Structure of Management
Information Version 2 (SMIv2)", STD 58, RFC 2578, April
1999.
[RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Textual Conventions for
SMIv2", STD 58, RFC 2579, April 1999.
[RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Conformance Statements for
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SMIv2", STD 58, RFC 2580, April 1999.
[RFC3513] Hinden, R. and S. Deering, "Internet Protocol Version 6
(IPv6) Addressing Architecture", RFC 3513, April 2003.
[RFCZZZZ] Deering, S., Haberman, B., Jinmei, T., Nordmark, E., Onoe,
A. and B. Zill, "IPv6 Scoped Address Architecture",
draft-ietf-ipv6-scoping-arch-00.txt, June 2003.
Informative References
[RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart,
"Introduction and Applicability Statements for the
Internet-Standard Management Framework", RFC 3410,
December 2002.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, June 2000.
[RFC2553] Gilligan, R., Thomson, S., Bound, J. and W. Stevens,
"Basic Socket Interface Extensions for IPv6", RFC 2553,
March 1999.
Authors' Addresses
Mike Daniele
Consultant
19 Pinewood Rd
Hudson, NH 03051
USA
Phone: +1 603 883-6365
EMail: md@world.std.com
Brian Haberman
Caspian Networks
1 Park Drive, Suite 300
Research Triangle Park, NC 27709
USA
Phone: +1 919-949-4828
EMail: brian@innovationslab.net
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Shawn A. Routhier
Wind River Systems, Inc.
500 Wind River Way
Alameda, CA 94501
USA
Phone: +1 510 749-2095
EMail: sar@epilogue.com
Juergen Schoenwaelder
International University Bremen
P.O. Box 750 561
28725 Bremen
Germany
Phone: +49 421 200-3587
EMail: j.schoenwaelder@iu-bremen.de
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Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
Full Copyright Statement
Copyright (C) The Internet Society (2004). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
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HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgment
Funding for the RFC Editor function is currently provided by the
Internet Society.
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