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 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Code | Length | Enterprise Number1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | DataLen1 | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + \ Suboption Data1 \Show full document text