RFC 2489 (rfc2489) - Page 2 of 5
Procedure for Defining New DHCP Options
Alternative Format: Original Text Document
RFC 2489 Defining New DCHP Options January 1999 As indicated in "Guidelines for Writing an IANA Considerations Section in RFCs" (see references), IANA acts as a central authority for assignment of numbers such as DHCP option codes. The new procedure outlined in this document will provide guidance to IANA in the assignment of new option codes. 2. Overview and background The procedure described in this document modifies and clarifies the procedure for defining new options in RFC 2131 [2]. The primary modification is to the time at which a new DHCP option is assigned an option number. In the procedure described in this document, the option number is not assigned until specification for the option is about to be published as an RFC. Since the publication of RFC 2132, the option number space for publically defined DHCP options (1-127) has almost been exhausted. Many of the defined option numbers have not been followed up with Internet Drafts submitted to the DHC WG. There has been a lack of specific guidance to IANA from the DHC WG as to the assignment of DHCP option numbers The procedure as specified in RFC 2132 does not clearly state that new options are to be reviewed individually for technical correctness, appropriateness and complete documentation. RFC 2132 also does not require that new options are to be submitted to the IESG for review, and that the author of the option specification is responsible for bringing new options to the attention of the IESG. Finally, RFC 2132 does not make clear that newly defined options are not to be incorporated into products, included in other specifications or otherwise used until the specification for the option is published as an RFC. In the future, new DHCP option codes will be assigned by IETF consensus. New DHCP options will be documented in RFCs approved by the IESG, and the codes for those options will be assigned at the time the relevant RFCs are published. Typically, the IESG will seek input on prospective assignments from appropriate sources (e.g., a relevant Working Group if one exists). Groups of related options may be combined into a single specification and reviewed as a set by the IESG. Prior to assignment of an option code, it is not appropriate to incorporate new options into products, include the specification in other documents or otherwise make use of the new options. The DHCP option number space (1-254) is split into two parts. The site-specific options (128-254) are defined as "Private Use" and require no review by the DHC WG. The public options (1-127) are Droms Best Current Practice



