Current Meeting Report

2.3.3 Dynamic Host Configuration (dhc)

In addition to this official charter maintained by the IETF Secretariat, there is additional information about this working group on the Web at: -- Additional DHC Page
NOTE: This charter is a snapshot of the 54th IETF Meeting in Yokohama, Japan. It may now be out-of-date.

Last Modifield: 05/24/2002

Ralph Droms <>
Internet Area Director(s):
Thomas Narten <>
Erik Nordmark <>
Internet Area Advisor:
Thomas Narten <>
Mailing Lists:
General Discussion:
To Subscribe:
Description of Working Group:
Other Lists:

A separate mailing list is used for discussing the IPv6 version of dhcp:

This working group has developed DHCP for automated allocation, configuration and management of IP addresses and TCP/IP protocol stack parameters. DHCP is currently a "Draft Standard" (RFC2131, RFC2132). The working group now has four main objectives:

* Revise and submit the DHCP specification for acceptance as a Full Standard

* Develop a roadmap for the review and acceptance of new options, define a new option syntax, develop an accurate list of assigned option codes and identify option codes that can be safely reassigned

* Develop a specification for DHCP for IPv6

* Develop an inter-server communication for coordination of multiple servers

* Review new options for DHCP, as deemed appropriate by the working group chair and/or the Internet area directors; specific options currently under review in the working group include:

o Mechanisms for the authentication of clients and servers

o Interaction between DHCP and DNS dynamic update protocol

o Definition of a DHCP MIB for management of DHCP servers through SNMP

o Definition of an LDAP schema to provide a standardized format for the storage and retrieval of DHCP information, primarily configuration and lease data; this schema will be developed in coordination with the Policy Frameworks Working Group as appropriate.

o Options through which DHCP relay agents can pass information to DHCP servers

o Other options: user class, server selection, domain search

Goals and Milestones:
JUN 99  Submit Internet-Draft on subnet selection option in time for Oslo IETF
JUN 99  Submit Internet-Draft on DAP schema for DHCP in time for Oslo IETF
JUN 99  Submit Internet-Draft on DHCP authentication in time for Oslo IETF
JUN 99  Submit Internet-Draft on failover protocol in time for Oslo IETF
JUN 99  Submit Internet-Draft on relay agent options in time for Oslo IETF
JUN 99  Submit Internet-Draft on DHCP-DNS interaction in time for Oslo IETF
JUL 99  Submit Internet-Draft on DHCP authentication for WG last call
JUL 99  Develop plan for review of DHCP specification and acceptance as Internet Standard.
SEP 99  Submit DHCP server MIB specification for WG last call
SEP 99  Submit subnet selection option specification for WG Last Call
NOV 99  Submit DHCP server MIB specification for IESG consideration as a Proposed Standard
NOV 99  Submit LDAP schema specification for WG last call
MAR 00  Submit LDAP schema specification to IESG for consideration as a Proposed Standard.
  • - draft-ietf-dhc-dhcpv6-26.txt
  • - draft-ietf-dhc-failover-10.txt
  • - draft-ietf-dhc-server-mib-06.txt
  • - draft-ietf-dhc-csr-07.txt
  • - draft-ietf-dhc-packetcable-02.txt
  • - draft-ietf-dhc-fqdn-option-04.txt
  • - draft-ietf-dhc-ddns-resolution-04.txt
  • - draft-ietf-dhc-leasequery-03.txt
  • - draft-ietf-dhc-concat-04.txt
  • - draft-ietf-dhc-agent-vpn-id-01.txt
  • - draft-ietf-dhc-agent-subnet-selection-03.txt
  • - draft-ietf-dhc-dhcpv6-opt-dstm-01.txt
  • - draft-ietf-dhc-dhcpv6-opt-dnsconfig-02.txt
  • - draft-ietf-dhc-agentopt-radius-00.txt
  • - draft-ietf-dhc-dhcpv6-loadb-01.txt
  • - draft-ietf-dhc-dhcpv6-opt-dstm-ports-01.txt
  • - draft-ietf-dhc-dhcpv6-opt-timeconfig-01.txt
  • - draft-ietf-dhc-dhcpv6-opt-nisconfig-01.txt
  • - draft-ietf-dhc-host-option-considerations-00.txt
  • - draft-ietf-dhc-isnsoption-01.txt
  • - draft-ietf-dhc-dhcpv6-opt-cliprefprefix-00.txt
  • - draft-ietf-dhc-auth-suboption-00.txt
  • Request For Comments:
    RFC1531 PS Dynamic Host Configuration Protocol
    RFC1532 PS Clarifications and Extensions for the Bootstrap Protocol
    RFC1533 PS DHCP Options and BOOTP Vendor Extensions
    RFC1534 DS Interoperation Between DHCP and BOOTP
    RFC1541 PS Dynamic Host Configuration Protocol
    RFC1542 DS Clarifications and Extensions for the Bootstrap Protocol
    RFC2132 DS DHCP Options and BOOTP Vendor Extensions
    RFC2131 DS Dynamic Host Configuration Protocol
    RFC2242 PS Netware/IP Domain Name and Information
    RFC2241 PS DHCP Options for Novell Directory Services
    RFC2485 PS DHCP Option for The Open Group's User Authentication Protocol
    RFC2489BCPProcedure for Defining New DHCP Options
    RFC2563 PS DHCP Option to Disable Stateless Auto-Configuration in IPv4 Clients
    RFC2610 PS DHCP Options for Service Location Protocol
    RFC2939BCPProcedure for Defining New DHCP Options and Message Types
    RFC2937 PS The Name Service Search Option for DHCP
    RFC3011 PS The Subnet Selection Option for DHCP
    RFC3004 PS The User Class Option for DHCP
    RFC3046 PS DHCP Relay Agent Information Option
    RFC3074 PS DHC load balancing algorithm
    RFC3118 PS Authentication for DHCP Messages
    RFC3203 PS DHCP reconfigure extension
    RFC3256 PS The DOCSIS Device Class DHCP Relay Agent Information Sub-option

    Current Meeting Report

    DHC WG

    These minutes were prepared from notes taken by Stuart Cheshire and Ted Lemon.

    Status report
    Ralph started the meeting with a WG status report.

    Ralph announced the publication of "DHCP Auto-configure Option (Option code 116) Deprecated" <draft-droms-rfc2563-deprecate-00.txt>.
    It will go to WG last call after publication of <draft-zeroconf-ip4-linkloocal-xx.txt> as Proposed Standard.

    Matt Osman, <draft-ietf-dhc-packetcable-02.txt>
    Matt Osman presented the "DHCP Option for CableLabs Client Configuration". This option will redefine the option 177 currently in use by CableLabs.

    Narten: Why not use vendor-specific options?
    Droms: Device can only have one vendor identifier; can't specify both vendor and "CableLabs-compatible" as vendor type.
    Droms: Two issues from chair's point of view: CableLabs wants to work with IETF to generate Internet Standard for function now deployed in option 177 (note that 177 is from the site-defined option code space); this draft proposes a somewhat different mechanism for sub-option code assignment.
    Narten: Does this option fundamentally change the way DHCP works? WG members should consider that issue when reading the draft.
    Woundy: CableLabs is not looking for IETF/DHCWG to rubberstamp this draft. CableLabs wants to go through IETF process and standardize the use of this option.

    The draft had not been read by the WG. Ralph will give the WG two weeks to read the draft (to begin 7/22), and then start WG last call.

    Ralph pointed out the publication of "The Authentication Suboption for the DHCP Relay Agent Option". This draft is a result of a discussion from the Minneapolis DHC WG meeting. There are open issues in the draft that will be discussed on the WG mailing list: hwo does a device that doesn't set 'giaddr' get the response from the DHCP server so the device cna remove its realy agent options; should the DHCP specification be extended to explicitly allow chaining of relay agents (as in DHCPv6)?

    "DHCP Lease Query" <draft-ietf-dhc-leasequery-03.txt> is in WG last call. There have been some comments posted during the last call. WG members were requested to further review the draft.

    "Dynamic Host Configuration Protocol (DHCP) Server MIB"
    <draft-ietf-dhc-server-mib-06.txt> is in WG last call. There have been some comments posted during the last call. The authors will respond to the comments and work with Rich Woundy to revise the draft.

    Narten: Deos this MIB have utility?
    Droms: Every time Barr Hibbs has asked, WG consensus has been to continue work on the MIB.
    Narten: Does anyone plaen to implement this MIB?
    Droms: Cisco does.
    Woundy: CableLabs wants to build embedded DHCP servers in modems.
    Some tables from this MIB would be useful.
    Waters: Version -07 seems to have been lost; will work with Hibbs to get versions straightened out.
    Scanner: The -06 version is quite ISC-specific.
    Droms: Please submit comments about that issue to the mailing list.

    <draft-ietf-dhc-concat-04.txt>, <draft-ietf-dhc-csr-07.txt>, <draft-aboba-dhc-domsearch-09.txt>
    The ADs have the token for review of "Encoding Long Options in DHCPv4" <draft-ietf-dhc-concat-04.txt>, "The Classless Static Route Option for DHCPv4" <draft-ietf-dhc-csr-07.txt> and "DHCP Domain Search Option" <draft-aboba-dhc-domsearch-09.txt>.

    Ralph announced the status of the DHCPv6 spec: the -26 rev has been reviewed by some IESG members and the authors are preparing a new rev with responses to those reviews. In particular, the WG was alerted to changes in authentication and reconfiguration machinery. Ralph asked the WG to consider two issues: should the DHCPv6 authentication mechanism be identified as a separate authentication protocol wihtin the RFC3118 framework and should the "reconfiguration nonce" option be merged into the RFC 3118 framework. Some support was expressed for the latter suggestion.

    Ole Troan, <draft-troan-dhcpv6-opt-prefix-delegation-01.txt>
    Ole Troan gave an update presentation on "IPv6 Prefix Options for DHCPv6" <draft-troan-dhcpv6-opt-prefix-delegation-01.txt> option. Ralph mentioned that the IPv6 WG is working on a set of requirements and a selectin process for prefix delegation. There was some discussion about modifications to the PD option to solve larger scale problems - spec., make PD look more like Identity Association, with an ID and similar semantics. Authors will revise draft to accommodate tat suggestion.

    Other DHCPv6 option drafts
    Ralph asked if the WG had reviewed the other DHCPv6 option drafts:
    DNS Configuration options for DHCPv6 <draft-ietf-dhc-dhcpv6-opt-dnsconfig-02.txt>
    NIS Configuration Options for DHCPv6 <draft-ietf-dhc-dhcpv6-opt-nisconfig-01.txt>
    Time Configuration Options for DHCPv6 <draft-ietf-dhc-dhcpv6-opt-timeconfig-01.txt>
    DSTM Options for DHCP <draft-ietf-dhc-dhcpv6-opt-dstm-01.txt>
    Client Preferred Prefix option for DHCPv6 <draft-ietf-dhc-dhcpv6-opt-cliprefprefix-00.txt>
    Some discussion of the use of DHCP for service configuration ensued. Do we need a TTL field for service configuration options? Other server controls? What's the problem to be solved? How does T1/T2 not solve this problem today? What's the overlap with the service discovery protocol space?

    DHC WG Charter
    Ralph led a discussion of the WG charter. He did some real-time edits on the charter. He will wordsmith the edits and continue the discussion on the WG mailing list.


    PacketCable DHCP Option Code
    IPv6 Prefix Delegation Options for DHCPv6