Vendor-Specific Information Suboption for the Dynamic Host Configuration Protocol (DHCP) Relay Agent Option
RFC 4243
| Document | Type | RFC - Proposed Standard (December 2005; No errata) | |
|---|---|---|---|
| Authors | Richard Johnson , Mark Stapp , Theyn Palaniappan | ||
| Last updated | 2013-03-02 | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text html pdf htmlized (tools) htmlized bibtex | ||
| Stream | WG state | (None) | |
| Document shepherd | No shepherd assigned | ||
| IESG | IESG state | RFC 4243 (Proposed Standard) | |
| Action Holders |
(None)
|
||
| Consensus Boilerplate | Unknown | ||
| Telechat date | |||
| Responsible AD | Margaret Cullen | ||
| Send notices to | rdroms@cisco.com, venaas@uninett.no | ||
Network Working Group M. Stapp
Request for Comments: 4243 R. Johnson
Category: Standards Track T. Palaniappan
Cisco Systems, Inc.
December 2005
Vendor-Specific Information Suboption for the
Dynamic Host Configuration Protocol (DHCP) Relay Agent Option
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2005).
Abstract
This memo defines a new Vendor-Specific Information suboption for the
Dynamic Host Configuration Protocol's (DHCP) relay agent information
option. The suboption allows a DHCP relay agent to include vendor-
specific information in the DHCP messages it forwards, as configured
by its administrator.
Table of Contents
1. Introduction ....................................................2
2. Requirements Terminology ........................................2
3. The Vendor-Specific Suboption ...................................2
4. Relay Agent Behavior ............................................4
5. DHCP Server Behavior ............................................4
6. Security Considerations .........................................4
7. IANA Considerations .............................................5
8. Acknowledgements ................................................5
Normative References ...............................................5
Informative References .............................................5
Stapp, et al. Standards Track [Page 1]
RFC 4243 Vendor-Specific Relay Suboption December 2005
1. Introduction
DHCP (RFC 2131 [2]) provides IP addresses and configuration
information for IPv4 clients. It includes a relay agent capability,
in which processes within the network infrastructure receive
broadcast messages from clients and forward them to DHCP servers as
unicast messages. In network environments like DOCSIS data-over-
cable and xDSL, for example, it has proven useful for the relay agent
to add information to the DHCP message before forwarding it, using
the relay agent information option (RFC 3046 [3]).
Servers that recognize the relay agent option echo it back in their
replies, and some of the information that relays add may be used to
help an edge device efficiently return replies to clients. The
information that relays supply can also be used in the server's
decision making about the addresses and configuration parameters that
the client should receive.
In many environments, it's desirable to associate some vendor- or
provider-specific information with the clients' DHCP messages. This
is often done using the relay agent information option. RFC 3046
defines Remote-ID and Circuit-ID sub-options that are used to carry
such information. The values of those suboptions, however, are
usually based on some network resource, such as an IP address of a
network access device, an ATM Virtual Circuit identifier, or a DOCSIS
cable-modem identifier. As a result, the values carried in these
suboptions are dependent on the physical network configuration. The
Vendor-Specific suboption allows administrators to associate other
useful data with relayed DHCP messages.
2. Requirements Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [1].
3. The Vendor-Specific Suboption
This memo defines a new DHCP relay agent option suboption that
carries vendor-defined data. The suboption takes a form similar to
the Vendor-Identifying, Vendor-Specific Option [7].
Stapp, et al. Standards Track [Page 2]
RFC 4243 Vendor-Specific Relay Suboption December 2005
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