Network Working Group
Pratik Gupta, IBM INTERNET DRAFT Glenn Stump,P. Gupta Internet Draft IBM July 1997 Expires JanuaryCorporation Obsoletes: draft-ietf-dhc-domsrch-00.txt November 1998 Expires May 1999 The Domain Search Option for DHCP <draft-ietf-dhc-domsrch-00.txt><draft-ietf-dhc-domsrch-01.txt> Status of this Memo This document is an Internet-Draft. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as ``work"work in progress.''progress". To learn the current status of any Internet-Draft, please check the ``1id-abstracts.txt''"1id-abstracts.txt" listing contained in the Internet-Drafts Shadow Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe), munnari.oz.au (Pacific Rim), ds.internic.netftp.ietf.org (US East Coast), or ftp.isi.edu (US West Coast). 1.0Abstract The Dynamic Host Configuration Protocol (DHCP) (DHCP) provides a framework for passing configuration information to hosts on a TCP/IP network. This document defines a new option which is passed form the DHCP serverServer to the DHCP Client to configure the domain search list which is used by the clients to resolve hostnames in the Domain Name System. 2.0System. Introduction RFC 2132 allows the Domain Name option(option 15) and the Domain Name Server (option 6) to be passed to the DHCP client. This information is used to resolve names in the Domain Name System. These options are usually used to configureplaced in the resolv.conf file on most operating systems. This information is usedThe name resolution routines on the client are also capable of using a domain search list that allows name resolution to resolve namesbe attempted in thea number of domains in sequence. The Domain Name System. This option allowesSearch Option allows a list of domain namesnames, in theorder of preferencepreference, to be passed to the DHCP client such that the search directive can be specified for name resolution. 3.0Definitions Throughout this document, the words that are used to define the significance of the particular requirements are capitalized. These words are: MUST"MUST" This word or the adjective "REQUIRED" means that the item is an absolute requirement of this specification. MUST NOT"MUST NOT" This phrase means the item is an absolute prohibition of this specification. SHOULD"SHOULD" This word or the adjective "RECOMMENDED" means that there may exist valid reasons in particular circumstances to ignore this item, but the full implications should be understood and the case carefully weighed before choosing a different course. SHOULD NOT"SHOULD NOT" This phrase means that there may exist valid reasons in particular circumstances when the listed behavior is acceptable or even useful, but the full implications should be understood and the case carefully weighted before implementing any behavior described with this label. MAY"MAY" This word or the adjective "OPTIONAL" means that this item is truly optional. One vendor may choose to include the item because a particular marketplace requires it or because it enhances the product, for example, another vendor may omit the same item. This document also uses the following terms: o"DHCP client" DHCP client or "client" is an Internet host using DHCP to obtain configuration parameters such as a network address. o"DHCP server" A DHCP server of "server"isor "server" is an Internet host that returns configuration parameters to DHCP clients. 3.0Domain Search Option Format The code for this option is TBD, and its minimum length is 2 bytes. Code Len Priority +-------+-------+-------+--------+---------+---------+--Domain Names in Sequence +-------+-------+-------+--------+---------+- | TBD | n | d1 | 00x20 | d2 | 0 | +-------+-------+-------+--------+---------+---------+-- where:+-------+-------+-------+--------+---------+- Where d1 & d2 are domain names 4.0specified as NVT ASCII strings. An ASCII space character (0x20) is used as a separator between the domain names. DHCP Client Behavior The DHCP client will use this option to create a domain search list for name resolution. If a DHCP client is given both a Domain Name Option and a Domain Search Option, the Domain Search Option will take precedence. 5.0Security Considerations DHCP currently provides no authentication or security mechanisms. Potential exposures to attack are discussed in section 7 of the DHCP protocol specification . 6.0References [RFC1533] S. Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997.  Alexander, R.S. and Droms, R., "DHCP Options and BOOTP Vendor Extensions" [RFC1541] R. Droms, "Dynamic Host Configuration Protocol" 7.0 Acknowledgments 8.0Extensions", RFC 2132, March 1997.  Mockapetris, P. V., "Domain names - implementation and specification", RFC 1035, November 1987. Author Information Pratik Gupta IBM, Inc.IBM Corporation 4205 S.Miami Blvd Research Triangle Park, NC 27709 Phone: (919)254-5654 email: firstname.lastname@example.org Glenn Stump IBM, Inc. 4205 S.Miami Blvd Research Triangle Park, NC 27709 Phone: (919)254-5616 email: email@example.com@us.ibm.com Expiration This document will expire on May 31, 1999. Full Copyright Statement Copyright (C) The Internet Society (1998). 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. 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