Network Working Group R. Droms
Request for Comments: 3679 Cisco Systems
Category: Informational January 2004
Unused Dynamic Host Configuration Protocol (DHCP) Option Codes
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
Prior to the publication of RFC 2489 (which was updated by RFC 2939),
several option codes were assigned to proposed Dynamic Host
Configuration Protocol (DHCP) options that were subsequently never
used. This document lists those unused option codes and directs IANA
to make these option codes available for assignment to other DHCP
options in the future.
The document also lists several option codes that are not currently
documented in an RFC but should not be made available for
reassignment to future DHCP options.
Section 2 of this document lists the unused DHCP option codes from
the IANA list of BOOTP and DHCP option codes [1]. Each option code
includes any known documentation and contact information from the
IANA list. IANA will make these option codes available for
assignment to other DHCP options in the future.
Section 3 lists several DHCP option codes that are not currently
documented in an RFC but should not be made available for
reassignment to future DHCP options.
The option codes listed in this section are to be returned to IANA
for reassignment to new options. Responses from associated contact
persons are noted where they have been received.
Droms Informational [Page 1]
RFC 3679 Unused DHCP Option Codes January 2004
Code: 80
Name: Service Location Protocol Naming Authority
Defined in: (expired Internet-Draft)
Contact: Charlie Perkins
Reason to recover: Never published as standard and not in general use
Codes: 83, 84
Name: Relay Agent Options
Defined in: Early draft of RFC 3046 [2]
Contact: (none)
Reason to recover: Not defined in RFC 3046 as published
Code: 88
Name: IEEE 1003.1 POSIX Timezone
Defined in: (expired Internet-Draft)
Contact: Mike Carney
Reason to recover: Never published as standard and not in general use
Code: 89
Name: FQDNs in DHCP Options
Defined in: (expired Internet-Draft)
Contact: Ralph Droms; agrees that option code should be
reassigned
Reason to recover: Never published as standard and not in general use
Code: 92
Name: Server Selection
Defined in: (none)
Contact: (none)
Reason to recover: Never published as Internet-Draft
Droms Informational [Page 2]
RFC 3679 Unused DHCP Option Codes January 2004
Code: 96
Name: IPv6 Transition
Defined in: (expired Internet-Draft)
Contact: Dan Harrington; agrees that option code should be
reassigned
Reason to recover: Never published as standard and not in general use
Code: 101
Name: Multicast Assignment through DHCP
Defined in: (expired Internet-Draft)
Contact: Baiju Patel, Munil Shah
Reason to recover: Never published as standard and not in general use
Code: 110
Name: IPX Compatibility
Defined in: (none)
Contact: Juan Luciani; agrees that option code should be
reassigned
Reason to recover: Never published as Internet-Draft
Droms Informational [Page 3]
RFC 3679 Unused DHCP Option Codes January 2004
Code: 115
Name: Failover
Defined in: Early revisions of "DHCP Failover Protocol" [3]
Contact: Kim Kinnear
Reason to recover: Current version of "DHCP Failover Protocol" does
not use a DHCP option
The option codes listed in this section are the subject of ongoing
work in the DHC Working Group (WG). These option codes should remain
on the IANA list of assigned option codes [1] until the DHC WG has
made a final decision about their disposition.
The following option codes are used in the "Preboot Execution
Environment (PXE) Specification, Version 2.1" [4]. However, although
these options are in widespread use by devices that use PXE, none of
these option codes have been described in a published RFC.
The DHC WG will endeavor to have specifications for these options
published.
Code: 93
Name: Client System
Defined in: "Preboot Execution Environment (PXE)
Specification, Version 2.1" [4]
Contact: Michael Johnston
(frenchy@quiet-like-a-panther.org)
The following option codes are used by devices from Apple Computer.
However, none of these option codes have been described in a
published RFC.
The DHC WG will endeavor to have specifications for these options
published.
Codes: 112, 113
Name: Netinfo Address, Netinfo Tag
Defined in: (none)
Contact: Dieter Siegmund, dieter@apple.com
Reason to recover: Never published in an RFC
Code: 114
Name: URL
Defined in: (none)
Contact: Dieter Siegmund, dieter@apple.com
Reason to recover: Never published in an RFC
Droms Informational [Page 5]
RFC 3679 Unused DHCP Option Codes January 2004
Note that these option codes are identified in "Extending DHCP
Options Codes" [5] as part of a mechanism for extending the set of
option codes available to DHCP. If these option codes are not used
for DHCP option code extension, they will be returned to IANA for
reassignment to other DHCP options.
Codes: 126, 127
Name: Option Code Extensions
Defined in: (expired Internet-Draft)
Contact: Ralph Droms
IANA has returned the DHCP option codes listed in Section 2 to the
list of available option codes. These option codes may be reassigned
to new DHCP options, according to the procedures in RFC 2939 [6].
IANA is requested to reassign these option codes after the list of
option codes that have never been assigned or have previously been
returned has been exhausted.
Informative References
[1] Assigned Numbers Editor, IANA., "BOOTP and DHCP Parameters",
http://www.iana.org/assignments/bootp-dhcp-parameters, February
2003.
[2] Patrick, M., "DHCP Relay Agent Information Option", RFC 3046,
January 2001.
[3] Droms, R., Kinnear, K., Stapp, M., Volz, B., Gonczi, S., Rabil,
G., Dooley, M. and A. Kapur, "DHCP Failover Protocol", Work in
Progress.
[4] Intel Corporation, "Preboot Execution Environment (PXE)
Specification Version 2.1", http://www.pix.net/software/pxeboot/
archive/pxespec.pdf, September 1999.
Droms Informational [Page 6]
RFC 3679 Unused DHCP Option Codes January 2004
[5] Volz, B., Droms, R. and T. Lemon, "Extending DHCP Options
Codes", Work in Progress.
[6] Droms, R., "Procedures and IANA Guidelines for Definition of New
DHCP Options and Message Types", BCP 43, RFC 2939, September
2000.
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.
Author's Address
Ralph Droms
Cisco Systems
1414 Massachusetts Avenue
Boxborough, MA 01719
USA
Phone: +1 978 936 1674
EMail: rdroms@cisco.com
Droms Informational [Page 7]
RFC 3679 Unused DHCP Option Codes January 2004
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
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Droms Informational [Page 8]