
Date: Tue, 15 Oct 1996 17:55:30 -0700
From: donp@sjf.novell.com (don provan)
To: iana@isi.edu
Subject: request for three DHCP option codes


Network Working Group                                         don provan
INTERNET DRAFT                                              Novell, Inc.
                                                         15 October 1996


                DHCP Options for Novell Directory Services
                       draft-provan-nds-dhcpopt-00.txt


Abstract

   This document defines three new DHCP options for delivering
   configuration information to clients of the Novell Directory
   Services. The first option carries a list of NDS servers. The
   second option carries the name of the client's NDS tree. The third
   carries the initial NDS context. These three options provide an NDS
   client with enough information to connect to an NDS tree without
   manual configuration of the client.
   

Status of this Memo

   This document is being written in preparation for submission to the
   DHCP Working Group of the Internet Engineering Task Force (IETF).
   Comments should be submitted either to the author, or to the DHCP
   mailing list.
   
   Distribution of this memo is unlimited.
   
   This document will be, but has not yet been, submitted as an
   Internet-Draft.  Internet Drafts are working documents of the
   Internet Engineering Task Force (IETF), its Areas, and its Working
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   munnari.oz.au (Pacific Rim).
   




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Internet Draft         DHCP Options for NDS              15 October 1996

1. Introduction

   Novell Directory Services is a distributed, replicated,
   hierarchical database of objects representing network resources
   such as nodes, services, users, and applications. An NDS client
   must be able to locate an NDS server in order to authenticate
   itself to the network and gain access to the database. In addition,
   the node's user is better served if the NDS client's attention is
   focused on the area of the NDS database likely to be of the most
   interest to the user.
   
   This specification describes DHCP options [1] that carry NDS
   information to TCP/IP clients of NDS. The first option, the NDS
   Servers option, carries a list of NDS servers. The other two
   options, the NDS Tree Name option and the NDS Context option,
   provide the client with a default context within the NDS database.
   

2. NDS Servers Option

   This option specifies one or more NDS servers for the client to
   contact for access to the NDS database. Servers SHOULD be listed in
   order of preference.
   
   The code for this option is 85. Its minimum length is
   4 octets, and the length MUST be a multiple of 4.
   
       Code   Len        Address 1               Address 2
      +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+--
      | 85  |  n  |  a1 |  a2 | a3  |  a4 |  a1 |  a2 |  a3 |  a4 |  ...
      +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+--


3. NDS Tree Name Option

   This option specifies the name of the NDS tree the client will be
   contacting. The tree name is formatted as a string of 16-bit
   Unicode characters, with each Unicode character transmitted in
   network order (most significant byte first).
   
   The code for this option is 86. Current
   implementations of NDS limit tree names to 32 Unicode characters
   (64 bytes), but implementations of this option are encouraged to
   support a maximum possible length for the option: 254 bytes. The
   length MUST be a multiple of 2.
   
       Code Len  NDS Tree Name
      +----+----+----+----+----+----+----+----+--
      | 86 | n  |   uc1   |   uc2   |   uc3   |  ...
      +----+----+----+----+----+----+----+----+--


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4. NDS Context Option

   This option specifies the initial NDS context the client should
   use. The context is formatted as a string of 16-bit Unicode
   characters, with each Unicode character transmitted in network
   order (most significant byte first).
   
   A single DHCP option can only contain 127 Unicode characters. Since
   an NDS context name can be longer than that, this option can appear
   more than once in the DHCP packet. The contents of all NDS Context
   options in the packet should be concatenated as suggested in the
   DHCP specification [2, page 23] to get the complete NDS context.
   
   The code for this option is 87. The length of each
   individual context option MUST be a multiple of 2. The maximum
   length for each instance is 254, but, as just described, the option
   may appear more than once if the desired NDS context is longer than
   127 Unicode characters. Current implementations of NDS limit
   contexts to 256 Unicode characters (512 bytes), but implementations
   are discouraged from enforcing any specific maximum to the final
   concatenated NDS context.
   
       Code Len  Initial NDS Context
      +----+----+----+----+----+----+----+----+--
      | 87 | n  |   uc1   |   uc2   |   uc3   |  ...
      +----+----+----+----+----+----+----+----+--


References

   [1] S. Alexander and R. Droms.  DHCP Options and BOOTP Vendor
       Extensions. draft-ietf-dhc-options-1533update-04.txt, May 1996.

   [2] R. Droms.  Dynamic Host Configuration Protocol.
       draft-ietf-dhc-dhcp-07.txt, May 1996.


Author's Address

   Don Provan
   Novell, Inc.
   2180 Fortune Drive
   San Jose, California, 95131

   Phone: +1 408 577 8440

   EMail: donp@Novell.Com





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