Internet Draft Michael Johnston Expiration: December, 2003 Intel Corporation File: draft-johnston-pxe-options-00.txt June, 2003 DHCP Preboot eXecution Environment Suboptions Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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 in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on December 18, 2003. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved. Abstract Define DHCP suboptions being used by PXE and EFI clients. Johnston [Page 1] Internet Draft DHCP Preboot eXecution Environment Suboptions March, 2003 Table of Contents Status of this Memo..............................................1 Copyright Notice.................................................1 Abstract.........................................................1 Table of Contents................................................2 Introduction.....................................................2 1.1. Conventions................................................2 2. Suboption Definitions........................................3 2.1. Client System Architecture Type Suboption Definition.......3 2.1.1 Client System Architecture Types..........................3 2.2. Client Network Interface Identifier Suboption Definition...3 2.3. Client Machine Identifier Suboption Definition.............4 References.......................................................4 Author Information...............................................4 Full Copyright Statement.........................................5 Introduction Three DHCP suboptions are being used to uniquely identify booting client machines and their pre-OS runtime environment so the DHCP and/or PXE [4] boot server can return the correct OS bootstrap image (or pre-boot application) name and server to the client. In the past, this work was done by examining the network MAC address in the "chaddr" field in the BOOTP/DHCP header and keeping a database of MAC addresses on the BOOTP/DHCP server. This was deemed insufficient for large and complex networks for two main reasons. 1) Multiple laptops could end up with the same MAC address if the NIC was in a shared docking station. 2) Multiple network devices and MAC addresses could be used by one machine for redundancy or because of repairs. Another issue that came up was the machine that could change its pre-OS runtime environment. This issue caused the creation of another new suboption to identify the runtime environment so the correct binary image could be matched up with the booting machine. 1.1. Conventions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [1]. Johnston [Page 2] Internet Draft DHCP Preboot eXecution Environment Suboptions March, 2003 2. Suboption Definitions 2.1. Client System Architecture Type Suboption Definition The format of the suboption is: Code Len 16-bit Type +----+-----+-----+-----+ | 93 | 2 | n1 | n2 | +----+-----+-----+-----+ Octets "n1" and "n2" encode a 16-bit architecture type identifier that describes the pre-boot runtime environment of the client machine.. 2.1.1 Client System Architecture Types As of the writing of this document the following pre-boot architecture types have been requested. At present, this list being maintained by the author. Type Architecture Name ---- ----------------- 0 Intel x86PC 1 NEC/PC98 2 EFI [5] Itanium 3 DEC Alpha 4 Arc x86 5 Intel Lean Client 6 EFI IA32 2.2. Client Network Interface Identifier Suboption Definition The format of the suboption is: Code Len Type Major Minor +----+-----+----+-----+-----+ | 94 | 3 | t | M | m | +----+-----+----+-----+-----+ Octet "t" encodes a network interface type. For now the only supported value is 1 for UNDI (Universal Network Device Interface). Octets "M" and "m" describe the interface revision. To encode the UNDI revision of 2.11, "M" would set to 2 and "m" would be set to 11 (0x0B). Johnston [Page 3] Internet Draft DHCP Preboot eXecution Environment Suboptions March, 2003 2.3. Client Machine Identifier Suboption Definition The format of the suboption is: Code Len Type Machine Identifier +----+-----+----+-----+ . . . +-----+ | 97 | n | t | | . . . | | +----+-----+----+-----+ . . . +-----+ Octet "t" describes the type of the machine identifier in the remaining octets in this suboption. 0 (zero) is the only defined value for this octet at the present time and it describes the remaining octets as a 16- octet GUID. (One definition of GUID can be found in Appendix A in the EFI specification [5].) References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, BCP 14, March 1997. [2] Droms, R. "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [3] Alexander, S. and Droms, R., "DHCP Options and BOOTP Vendor Extensions", RFC 2132, March 1997. [4] Henry, M. and Johnston, M., "Preboot Execution Environment (PXE) Specification", September 1999. ftp://download.intel.com/labs/manage/wfm/download/pxespec.pdf [5] Intel Corp., "Extensible Firmware Interface Specification", December 2002. http://developer.intel.com/technology/efi/main_specification.htm Author Information Michael Johnston Intel Corporation MS. JF1-239 2111 NE 25th Ave. Hillsboro, OR 97124 Phone: +1 503-264-9703 Email: michael.johnston@intel.com Johnston [Page 4] Internet Draft DHCP Preboot eXecution Environment Suboptions March, 2003 Full Copyright Statement Copyright (C) The Internet Society (2003). All Rights Reserved. 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This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY, THE INTERNET ENGINEERING TASK FORCE, THE AUTHOR AND THE AUTHOR’S EMPLOYER DISCLAIM 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. Johnston [Page 5]