draft-ietf-dhc-options-1533update-00.txt   draft-ietf-dhc-options-1533update-01.txt 
Network Working Group S. Alexander Network Working Group S. Alexander
INTERNET DRAFT Lachman Technology, Inc. INTERNET DRAFT Lachman Technology, Inc.
Obsoletes: draft-ietf-dhc-options-04.txt R. Droms Obsoletes: draft-ietf-dhc-options-1533update-00.txt R. Droms
Bucknell University Bucknell University
May 1995 September 1995
Expires November 1995 Expires March 1996
DHCP Options and BOOTP Vendor Extensions DHCP Options and BOOTP Vendor Extensions
<draft-ietf-dhc-options-1533update-00.txt> <draft-ietf-dhc-options-1533update-01.txt>
Status of this memo Status of this memo
This document is an Internet-Draft. Internet-Drafts are working This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas, documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute and its working groups. Note that other groups may also distribute
working documents as Internet-Drafts. working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
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The Dynamic Host Configuration Protocol (DHCP) [1] provides a The Dynamic Host Configuration Protocol (DHCP) [1] provides a
framework for passing configuration information to hosts on a TCP/IP framework for passing configuration information to hosts on a TCP/IP
network. Configuration parameters and other control information are network. Configuration parameters and other control information are
carried in tagged data items that are stored in the 'options' field carried in tagged data items that are stored in the 'options' field
of the DHCP message. The data items themselves are also called of the DHCP message. The data items themselves are also called
"options." "options."
This document specifies the current set of DHCP options. This This document specifies the current set of DHCP options. This
document will be periodically updated as new options are defined. document will be periodically updated as new options are defined.
Each superseding document will include the entire current list of Each superseding document will include the entire current list of
valid options. valid options. The current list of valid options is also available
in ftp://ftp.isi.edu/in-notes/iana/assignments [22].
All of the vendor information extensions defined in RFC 1497 [2] may All of the vendor information extensions defined in RFC 1497 [2] may
be used as DHCP options. The definitions given in RFC 1497 are be used as DHCP options. The definitions given in RFC 1497 are
included in this document, which supersedes RFC 1497. All of the included in this document, which supersedes RFC 1497. All of the
DHCP options defined in this document, except for those specific to DHCP options defined in this document, except for those specific to
DHCP as defined in section 9, may be used as BOOTP vendor information
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
DHCP as defined in section 9, may be used as BOOTP vendor information
extensions. extensions.
Table of Contents Table of Contents
1. Introduction .............................................. 2 1. Introduction .............................................. 2
2. BOOTP Extension/DHCP Option Field Format .................. 2 2. BOOTP Extension/DHCP Option Field Format .................. 2
3. RFC 1497 Vendor Extensions ................................ 3 3. RFC 1497 Vendor Extensions ................................ 3
4. IP Layer Parameters per Host .............................. 10 4. IP Layer Parameters per Host .............................. 10
5. IP Layer Parameters per Interface ........................ 13 5. IP Layer Parameters per Interface ........................ 13
6. Link Layer Parameters per Interface ....................... 16 6. Link Layer Parameters per Interface ....................... 16
7. TCP Parameters ............................................ 17 7. TCP Parameters ............................................ 17
8. Application and Service Parameters ........................ 18 8. Application and Service Parameters ........................ 18
9. DHCP Extensions ........................................... 26 9. DHCP Extensions ........................................... 26
10. Extensions ................................................ 32 10. Extensions ................................................ 33
11. Acknowledgements .......................................... 32 11. Acknowledgements .......................................... 33
12. References ................................................ 33 12. References ................................................ 33
13. Security Considerations ................................... 34 13. Security Considerations ................................... 35
14. Authors' Addresses ........................................ 35 14. Authors' Addresses ........................................ 35
A. Changes to draft-ietf-dhc-options-1533update-00.txt........ 36
1. Introduction 1. Introduction
This document specifies options for use with both the Dynamic Host This document specifies options for use with both the Dynamic Host
Configuration Protocol and the Bootstrap Protocol. Configuration Protocol and the Bootstrap Protocol.
The full description of DHCP packet formats may be found in the DHCP The full description of DHCP packet formats may be found in the DHCP
specification document [1], and the full description of BOOTP packet specification document [1], and the full description of BOOTP packet
formats may be found in the BOOTP specification document [3]. This formats may be found in the BOOTP specification document [3]. This
document defines the format of information in the last field of DHCP document defines the format of information in the last field of DHCP
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previous documents for use with BOOTP (all may also be used with previous documents for use with BOOTP (all may also be used with
DHCP). Sections 4-8 define new options intended for use with both DHCP). Sections 4-8 define new options intended for use with both
DHCP and BOOTP. Section 9 defines options used only in DHCP. DHCP and BOOTP. Section 9 defines options used only in DHCP.
References further describing most of the options defined in sections References further describing most of the options defined in sections
2-6 can be found in section 12. The use of the options defined in 2-6 can be found in section 12. The use of the options defined in
section 9 is described in the DHCP specification [1]. section 9 is described in the DHCP specification [1].
Information on registering new options is contained in section 10. Information on registering new options is contained in section 10.
2. BOOTP Extension/DHCP Option Field Format DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 2. BOOTP Extension/DHCP Option Field Format
DHCP options have the same format as the BOOTP 'vendor extensions' DHCP options have the same format as the BOOTP 'vendor extensions'
defined in RFC 1497 [2]. Options may be fixed length or variable defined in RFC 1497 [2]. Options may be fixed length or variable
length. All options begin with a tag octet, which uniquely length. All options begin with a tag octet, which uniquely
identifies the option. Fixed-length options without data consist of identifies the option. Fixed-length options without data consist of
only a tag octet. Only options 0 and 255 are fixed length. All only a tag octet. Only options 0 and 255 are fixed length. All
other options are variable-length with a length octet following the other options are variable-length with a length octet following the
tag octet. The value of the length octet does not include the two tag octet. The value of the length octet does not include the two
octets specifying the tag and length. The length octet is followed octets specifying the tag and length. The length octet is followed
by "length" octets of data. Options containing NVT ASCII data SHOULD by "length" octets of data. Options containing NVT ASCII data SHOULD
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Many of these options have their default values specified in other Many of these options have their default values specified in other
documents. In particular, RFC 1122 [4] specifies default values for documents. In particular, RFC 1122 [4] specifies default values for
most IP and TCP configuration parameters. most IP and TCP configuration parameters.
3. RFC 1497 Vendor Extensions 3. RFC 1497 Vendor Extensions
This section lists the vendor extensions as defined in RFC 1497. This section lists the vendor extensions as defined in RFC 1497.
They are defined here for completeness. They are defined here for completeness.
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.1. Pad Option 3.1. Pad Option
The pad option can be used to cause subsequent fields to align on The pad option can be used to cause subsequent fields to align on
word boundaries. word boundaries.
The code for the pad option is 0, and its length is 1 octet. The code for the pad option is 0, and its length is 1 octet.
Code Code
+-----+ +-----+
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If both the subnet mask and the router option are specified in a DHCP If both the subnet mask and the router option are specified in a DHCP
reply, the subnet mask option MUST be first. reply, the subnet mask option MUST be first.
The code for the subnet mask option is 1, and its length is 4 octets. The code for the subnet mask option is 1, and its length is 4 octets.
Code Len Subnet Mask Code Len Subnet Mask
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 1 | 4 | m1 | m2 | m3 | m4 | | 1 | 4 | m1 | m2 | m3 | m4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.4. Time Offset 3.4. Time Offset
The time offset field specifies the offset of the client's subnet in The time offset field specifies the offset of the client's subnet in
seconds from Coordinated Universal Time (UTC). The offset is seconds from Coordinated Universal Time (UTC). The offset is
expressed as a signed 32-bit integer. expressed as a signed 32-bit integer.
The code for the time offset option is 2, and its length is 4 octets. The code for the time offset option is 2, and its length is 4 octets.
Code Len Time Offset Code Len Time Offset
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The code for the time server option is 4. The minimum length for The code for the time server option is 4. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 4 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 4 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.7. Name Server Option 3.7. Name Server Option
The name server option specifies a list of IEN 116 [7] name servers The name server option specifies a list of IEN 116 [7] name servers
available to the client. Servers SHOULD be listed in order of available to the client. Servers SHOULD be listed in order of
preference. preference.
The code for the name server option is 5. The minimum length for The code for the name server option is 5. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
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preference. preference.
The code for the log server option is 7. The minimum length for this The code for the log server option is 7. The minimum length for this
option is 4 octets, and the length MUST always be a multiple of 4. option is 4 octets, and the length MUST always be a multiple of 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 7 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 7 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.10. Cookie Server Option 3.10. Cookie Server Option
The cookie server option specifies a list of RFC 865 [9] cookie The cookie server option specifies a list of RFC 865 [9] cookie
servers available to the client. Servers SHOULD be listed in order servers available to the client. Servers SHOULD be listed in order
of preference. of preference.
The code for the log server option is 8. The minimum length for this The code for the log server option is 8. The minimum length for this
option is 4 octets, and the length MUST always be a multiple of 4. option is 4 octets, and the length MUST always be a multiple of 4.
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The code for the Impress server option is 10. The minimum length for The code for the Impress server option is 10. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 10 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 10 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.13. Resource Location Server Option 3.13. Resource Location Server Option
This option specifies a list of RFC 887 [11] Resource Location This option specifies a list of RFC 887 [11] Resource Location
servers available to the client. Servers SHOULD be listed in order servers available to the client. Servers SHOULD be listed in order
of preference. of preference.
The code for this option is 11. The minimum length for this option The code for this option is 11. The minimum length for this option
is 4 octets, and the length MUST always be a multiple of 4. is 4 octets, and the length MUST always be a multiple of 4.
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boot image for the client. The file length is specified as an boot image for the client. The file length is specified as an
unsigned 16-bit integer. unsigned 16-bit integer.
The code for this option is 13, and its length is 2. The code for this option is 13, and its length is 2.
Code Len File Size Code Len File Size
+-----+-----+-----+-----+ +-----+-----+-----+-----+
| 13 | 2 | l1 | l2 | | 13 | 2 | l1 | l2 |
+-----+-----+-----+-----+ +-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.16. Merit Dump File 3.16. Merit Dump File
This option specifies the path-name of a file to which the client's This option specifies the path-name of a file to which the client's
core image should be dumped in the event the client crashes. The core image should be dumped in the event the client crashes. The
path is formatted as a character string consisting of characters from path is formatted as a character string consisting of characters from
the NVT ASCII character set. the NVT ASCII character set.
The code for this option is 14. Its minimum length is 1. The code for this option is 14. Its minimum length is 1.
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This specifies the IP address of the client's swap server. This specifies the IP address of the client's swap server.
The code for this option is 16 and its length is 4. The code for this option is 16 and its length is 4.
Code Len Swap Server Address Code Len Swap Server Address
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 16 | n | a1 | a2 | a3 | a4 | | 16 | n | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
3.19. Root Path 3.19. Root Path
This option specifies the path-name that contains the client's root This option specifies the path-name that contains the client's root
disk. The path is formatted as a character string consisting of disk. The path is formatted as a character string consisting of
characters from the NVT ASCII character set. characters from the NVT ASCII character set.
The code for this option is 17. Its minimum length is 1. The code for this option is 17. Its minimum length is 1.
Code Len Root Disk Pathname Code Len Root Disk Pathname
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This option specifies whether the client should configure its IP This option specifies whether the client should configure its IP
layer for packet forwarding. A value of 0 means disable IP layer for packet forwarding. A value of 0 means disable IP
forwarding, and a value of 1 means enable IP forwarding. forwarding, and a value of 1 means enable IP forwarding.
The code for this option is 19, and its length is 1. The code for this option is 19, and its length is 1.
Code Len Value Code Len Value
+-----+-----+-----+ +-----+-----+-----+
| 19 | 1 | 0/1 | | 19 | 1 | 0/1 |
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
+-----+-----+-----+ +-----+-----+-----+
4.2. Non-Local Source Routing Enable/Disable Option 4.2. Non-Local Source Routing Enable/Disable Option
This option specifies whether the client should configure its IP This option specifies whether the client should configure its IP
layer to allow forwarding of datagrams with non-local source routes layer to allow forwarding of datagrams with non-local source routes
(see Section 3.3.5 of [4] for a discussion of this topic). A value (see Section 3.3.5 of [4] for a discussion of this topic). A value
of 0 means disallow forwarding of such datagrams, and a value of 1 of 0 means disallow forwarding of such datagrams, and a value of 1
means allow forwarding. means allow forwarding.
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Code Len Address 1 Mask 1 Code Len Address 1 Mask 1
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| 21 | n | a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 | | 21 | n | a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Address 2 Mask 2 Address 2 Mask 2
+-----+-----+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+-----+-----+---
| a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 | ... | a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+-----+-----+---
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
4.4. Maximum Datagram Reassembly Size 4.4. Maximum Datagram Reassembly Size
This option specifies the maximum size datagram that the client This option specifies the maximum size datagram that the client
should be prepared to reassemble. The size is specified as a 16-bit should be prepared to reassemble. The size is specified as a 16-bit
unsigned integer. The minimum value legal value is 576. unsigned integer. The minimum value legal value is 576.
The code for this option is 22, and its length is 2. The code for this option is 22, and its length is 2.
Code Len Size Code Len Size
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MTU values discovered by the mechanism defined in RFC 1191 [12]. The MTU values discovered by the mechanism defined in RFC 1191 [12]. The
timeout is specified as a 32-bit unsigned integer. timeout is specified as a 32-bit unsigned integer.
The code for this option is 24, and its length is 4. The code for this option is 24, and its length is 4.
Code Len Timeout Code Len Timeout
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 24 | 4 | t1 | t2 | t3 | t4 | | 24 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
4.7. Path MTU Plateau Table Option 4.7. Path MTU Plateau Table Option
This option specifies a table of MTU sizes to use when performing This option specifies a table of MTU sizes to use when performing
Path MTU Discovery as defined in RFC 1191. The table is formatted as Path MTU Discovery as defined in RFC 1191. The table is formatted as
a list of 16-bit unsigned integers, ordered from smallest to largest. a list of 16-bit unsigned integers, ordered from smallest to largest.
The minimum MTU value cannot be smaller than 68. The minimum MTU value cannot be smaller than 68.
The code for this option is 25. Its minimum length is 2, and the The code for this option is 25. Its minimum length is 2, and the
length MUST be a multiple of 2. length MUST be a multiple of 2.
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specified as a 16-bit unsigned integer. The minimum legal value for specified as a 16-bit unsigned integer. The minimum legal value for
the MTU is 68. the MTU is 68.
The code for this option is 26, and its length is 2. The code for this option is 26, and its length is 2.
Code Len MTU Code Len MTU
+-----+-----+-----+-----+ +-----+-----+-----+-----+
| 26 | 2 | m1 | m2 | | 26 | 2 | m1 | m2 |
+-----+-----+-----+-----+ +-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
5.2. All Subnets are Local Option 5.2. All Subnets are Local Option
This option specifies whether or not the client may assume that all This option specifies whether or not the client may assume that all
subnets of the IP network to which the client is connected use the subnets of the IP network to which the client is connected use the
same MTU as the subnet of that network to which the client is same MTU as the subnet of that network to which the client is
directly connected. A value of 1 indicates that all subnets share directly connected. A value of 1 indicates that all subnets share
the same MTU. A value of 0 means that the client should assume that the same MTU. A value of 0 means that the client should assume that
some subnets of the directly connected network may have smaller MTUs. some subnets of the directly connected network may have smaller MTUs.
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should not perform mask discovery. A value of 1 means that the should not perform mask discovery. A value of 1 means that the
client should perform mask discovery. client should perform mask discovery.
The code for this option is 29, and its length is 1. The code for this option is 29, and its length is 1.
Code Len Value Code Len Value
+-----+-----+-----+ +-----+-----+-----+
| 29 | 1 | 0/1 | | 29 | 1 | 0/1 |
+-----+-----+-----+ +-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
5.5. Mask Supplier Option 5.5. Mask Supplier Option
This option specifies whether or not the client should respond to This option specifies whether or not the client should respond to
subnet mask requests using ICMP. A value of 0 indicates that the subnet mask requests using ICMP. A value of 0 indicates that the
client should not respond. A value of 1 means that the client should client should not respond. A value of 1 means that the client should
respond. respond.
The code for this option is 30, and its length is 1. The code for this option is 30, and its length is 1.
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This option specifies the address to which the client should transmit This option specifies the address to which the client should transmit
router solicitation requests. router solicitation requests.
The code for this option is 32, and its length is 4. The code for this option is 32, and its length is 4.
Code Len Address Code Len Address
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 32 | 4 | a1 | a2 | a3 | a4 | | 32 | 4 | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
5.8. Static Route Option 5.8. Static Route Option
This option specifies a list of static routes that the client should This option specifies a list of static routes that the client should
install in its routing cache. If multiple routes to the same install in its routing cache. If multiple routes to the same
destination are specified, they are listed in descending order of destination are specified, they are listed in descending order of
priority. priority.
The routes consist of a list of IP address pairs. The first address The routes consist of a list of IP address pairs. The first address
is the destination address, and the second address is the router for is the destination address, and the second address is the router for
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of 0 indicates that the client should not attempt to use trailers. A of 0 indicates that the client should not attempt to use trailers. A
value of 1 means that the client should attempt to use trailers. value of 1 means that the client should attempt to use trailers.
The code for this option is 34, and its length is 1. The code for this option is 34, and its length is 1.
Code Len Value Code Len Value
+-----+-----+-----+ +-----+-----+-----+
| 34 | 1 | 0/1 | | 34 | 1 | 0/1 |
+-----+-----+-----+ +-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
6.2. ARP Cache Timeout Option 6.2. ARP Cache Timeout Option
This option specifies the timeout in seconds for ARP cache entries. This option specifies the timeout in seconds for ARP cache entries.
The time is specified as a 32-bit unsigned integer. The time is specified as a 32-bit unsigned integer.
The code for this option is 35, and its length is 4. The code for this option is 35, and its length is 4.
Code Len Time Code Len Time
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
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sending TCP segments. The value is represented as an 8-bit unsigned sending TCP segments. The value is represented as an 8-bit unsigned
integer. The minimum value is 1. integer. The minimum value is 1.
The code for this option is 37, and its length is 1. The code for this option is 37, and its length is 1.
Code Len TTL Code Len TTL
+-----+-----+-----+ +-----+-----+-----+
| 37 | 1 | n | | 37 | 1 | n |
+-----+-----+-----+ +-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
7.2. TCP Keepalive Interval Option 7.2. TCP Keepalive Interval Option
This option specifies the interval (in seconds) that the client TCP This option specifies the interval (in seconds) that the client TCP
should wait before sending a keepalive message on a TCP connection. should wait before sending a keepalive message on a TCP connection.
The time is specified as a 32-bit unsigned integer. A value of zero The time is specified as a 32-bit unsigned integer. A value of zero
indicates that the client should not generate keepalive messages on indicates that the client should not generate keepalive messages on
connections unless specifically requested by an application. connections unless specifically requested by an application.
The code for this option is 38, and its length is 4. The code for this option is 38, and its length is 4.
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domain is formatted as a character string consisting of characters domain is formatted as a character string consisting of characters
from the NVT ASCII character set. from the NVT ASCII character set.
The code for this option is 40. Its minimum length is 1. The code for this option is 40. Its minimum length is 1.
Code Len NIS Domain Name Code Len NIS Domain Name
+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+---
| 40 | n | n1 | n2 | n3 | n4 | ... | 40 | n | n1 | n2 | n3 | n4 | ...
+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+---
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.2. Network Information Servers Option 8.2. Network Information Servers Option
This option specifies a list of IP addresses indicating NIS servers This option specifies a list of IP addresses indicating NIS servers
available to the client. Servers SHOULD be listed in order of available to the client. Servers SHOULD be listed in order of
preference. preference.
The code for this option is 41. Its minimum length is 4, and the The code for this option is 41. Its minimum length is 4, and the
length MUST be a multiple of 4. length MUST be a multiple of 4.
skipping to change at page 19, line 41 skipping to change at page 19, line 41
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 42 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 42 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
8.4. Vendor Specific Information 8.4. Vendor Specific Information
This option is used by clients and servers to exchange vendor- This option is used by clients and servers to exchange vendor-
specific information. The information is an opaque object of n specific information. The information is an opaque object of n
octets, presumably interpreted by vendor-specific code on the clients octets, presumably interpreted by vendor-specific code on the clients
and servers. The definition of this information is vendor specific. and servers. The definition of this information is vendor specific.
The vendor is indicated in the class-identifier option. Servers not The vendor is indicated in the vendor class identifier option.
equipped to interpret the vendor-specific information sent by a Servers not equipped to interpret the vendor-specific information
client MUST ignore it (although it may be reported). Clients which sent by a client MUST ignore it (although it may be reported).
do not receive desired vendor-specific information SHOULD make an Clients which do not receive desired vendor-specific information
attempt to operate without it, although they may do so (and announce SHOULD make an attempt to operate without it, although they may do so
they are doing so) in a degraded mode. (and announce they are doing so) in a degraded mode.
If a vendor potentially encodes more than one item of information in If a vendor potentially encodes more than one item of information in
this option, then the vendor SHOULD encode the option using this option, then the vendor SHOULD encode the option using
"Encapsulated vendor-specific options" as described below: "Encapsulated vendor-specific options" as described below:
The Encapsulated vendor-specific options field SHOULD be encoded as a The Encapsulated vendor-specific options field SHOULD be encoded as a
sequence of code/length/value fields of identical syntax to the DHCP sequence of code/length/value fields of identical syntax to the DHCP
options field with the following exceptions: options field with the following exceptions:
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1) There SHOULD NOT be a "magic cookie" field in the encapsulated 1) There SHOULD NOT be a "magic cookie" field in the encapsulated
vendor-specific extensions field. vendor-specific extensions field.
2) Codes other than 0 or 255 MAY be redefined by the vendor within 2) Codes other than 0 or 255 MAY be redefined by the vendor within
the encapsulated vendor-specific extensions field, but SHOULD the encapsulated vendor-specific extensions field, but SHOULD
conform to the tag-length-value syntax defined in section 2. conform to the tag-length-value syntax defined in section 2.
3) Code 255 (END), if present, signifies the end of the 3) Code 255 (END), if present, signifies the end of the
encapsulated vendor extensions, not the end of the vendor encapsulated vendor extensions, not the end of the vendor
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1001/1002 [19] [20] NBNS name servers listed in order of preference. 1001/1002 [19] [20] NBNS name servers listed in order of preference.
The code for this option is 44. The minimum length of the option is The code for this option is 44. The minimum length of the option is
4 octets, and the length must always be a multiple of 4. 4 octets, and the length must always be a multiple of 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+---- +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+----
| 44 | n | a1 | a2 | a3 | a4 | b1 | b2 | b3 | b4 | ... | 44 | n | a1 | a2 | a3 | a4 | b1 | b2 | b3 | b4 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+---- +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+----
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.6. NetBIOS over TCP/IP Datagram Distribution Server Option 8.6. NetBIOS over TCP/IP Datagram Distribution Server Option
The NetBIOS datagram distribution server (NBDD) option specifies a The NetBIOS datagram distribution server (NBDD) option specifies a
list of RFC 1001/1002 NBDD servers listed in order of preference. The list of RFC 1001/1002 NBDD servers listed in order of preference. The
code for this option is 45. The minimum length of the option is 4 code for this option is 45. The minimum length of the option is 4
octets, and the length must always be a multiple of 4. octets, and the length must always be a multiple of 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+---- +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+----
skipping to change at page 22, line 5 skipping to change at page 22, line 5
(hexadecimal). (hexadecimal).
The code for this option is 46. The length of this option is always The code for this option is 46. The length of this option is always
1. 1.
Code Len Node Type Code Len Node Type
+-----+-----+-----------+ +-----+-----+-----------+
| 46 | 1 | see above | | 46 | 1 | see above |
+-----+-----+-----------+ +-----+-----+-----------+
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8.8. NetBIOS over TCP/IP Scope Option 8.8. NetBIOS over TCP/IP Scope Option
The NetBIOS scope option specifies the NetBIOS over TCP/IP scope The NetBIOS scope option specifies the NetBIOS over TCP/IP scope
parameter for the client as specified in RFC 1001/1002. See [19], parameter for the client as specified in RFC 1001/1002. See [19],
[20], and [8] for character-set restrictions. [20], and [8] for character-set restrictions.
The code for this option is 47. The minimum length of this option is The code for this option is 47. The minimum length of this option is
1. 1.
skipping to change at page 23, line 5 skipping to change at page 23, line 5
The code for the this option is 49. The minimum length of this option The code for the this option is 49. The minimum length of this option
is 4, and the length MUST be a multiple of 4. is 4, and the length MUST be a multiple of 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+-----+-----+---
| 49 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 49 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+-----+-----+-----+---
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.11. Network Information Service+ Domain Option 8.11. Network Information Service+ Domain Option
This option specifies the name of the client's NIS+ [17] domain. The This option specifies the name of the client's NIS+ [17] domain. The
domain is formatted as a character string consisting of characters domain is formatted as a character string consisting of characters
from the NVT ASCII character set. from the NVT ASCII character set.
The code for this option is 64. Its minimum length is 1. The code for this option is 64. Its minimum length is 1.
Code Len NIS Client Domain Name Code Len NIS Client Domain Name
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The code for this option is 68. Its minimum length is 0 (indicating The code for this option is 68. Its minimum length is 0 (indicating
no home agents are available) and the length MUST be a multiple of 4. no home agents are available) and the length MUST be a multiple of 4.
It is expected that the usual length will be four octets, containing It is expected that the usual length will be four octets, containing
a single home agent's address. a single home agent's address.
Code Len Home Agent Addresses (zero or more) Code Len Home Agent Addresses (zero or more)
+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+--
| 68 | n | a1 | a2 | a3 | a4 | ... | 68 | n | a1 | a2 | a3 | a4 | ...
+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.14. Simple Mail Transport Protocol (SMTP) Server Option 8.14. Simple Mail Transport Protocol (SMTP) Server Option
The SMTP server option specifies a list of SMTP servers available to The SMTP server option specifies a list of SMTP servers available to
the client. Servers SHOULD be listed in order of preference. the client. Servers SHOULD be listed in order of preference.
The code for the SMTP server option is 69. The minimum length for The code for the SMTP server option is 69. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
skipping to change at page 25, line 5 skipping to change at page 25, line 5
The code for the NNTP server option is 71. The minimum length for The code for the NNTP server option is 71. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 71 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 71 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.17. Default World Wide Web (WWW) Server Option 8.17. Default World Wide Web (WWW) Server Option
The WWW server option specifies a list of WWW available to the The WWW server option specifies a list of WWW available to the
client. Servers SHOULD be listed in order of preference. client. Servers SHOULD be listed in order of preference.
The code for the WWW server option is 72. The minimum length for The code for the WWW server option is 72. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
skipping to change at page 26, line 5 skipping to change at page 26, line 5
The code for the IRC server option is 74. The minimum length for The code for the IRC server option is 74. The minimum length for
this option is 4 octets, and the length MUST always be a multiple of this option is 4 octets, and the length MUST always be a multiple of
4. 4.
Code Len Address 1 Address 2 Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
| 74 | n | a1 | a2 | a3 | a4 | a1 | a2 | ... | 74 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+-- +-----+-----+-----+-----+-----+-----+-----+-----+--
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
8.20. StreetTalk Server Option 8.20. StreetTalk Server Option
The StreetTalk server option specifies a list of StreetTalk servers The StreetTalk server option specifies a list of StreetTalk servers
available to the client. Servers SHOULD be listed in order of available to the client. Servers SHOULD be listed in order of
preference. preference.
The code for the StreetTalk server option is 75. The minimum length The code for the StreetTalk server option is 75. The minimum length
for this option is 4 octets, and the length MUST always be a multiple for this option is 4 octets, and the length MUST always be a multiple
of 4. of 4.
skipping to change at page 27, line 5 skipping to change at page 27, line 5
This option is used in a client request (DHCPDISCOVER) to allow the This option is used in a client request (DHCPDISCOVER) to allow the
client to request that a particular IP address be assigned. client to request that a particular IP address be assigned.
The code for this option is 50, and its length is 4. The code for this option is 50, and its length is 4.
Code Len Address Code Len Address
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 50 | 4 | a1 | a2 | a3 | a4 | | 50 | 4 | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
9.2. IP Address Lease Time 9.2. IP Address Lease Time
This option is used in a client request (DHCPDISCOVER or DHCPREQUEST) This option is used in a client request (DHCPDISCOVER or DHCPREQUEST)
to allow the client to request a lease time for the IP address. In a to allow the client to request a lease time for the IP address. In a
server reply (DHCPOFFER), a DHCP server uses this option to specify server reply (DHCPOFFER), a DHCP server uses this option to specify
the lease time it is willing to offer. the lease time it is willing to offer.
The time is in units of seconds, and is specified as a 32-bit The time is in units of seconds, and is specified as a 32-bit
unsigned integer. unsigned integer.
skipping to change at page 28, line 5 skipping to change at page 28, line 5
| 52 | 1 |1/2/3| | 52 | 1 |1/2/3|
+-----+-----+-----+ +-----+-----+-----+
9.4 TFTP server name 9.4 TFTP server name
This option is used to identify a TFTP server when the 'sname' This option is used to identify a TFTP server when the 'sname'
field in the DHCP header has been used for DHCP options. field in the DHCP header has been used for DHCP options.
The code for this option is 66, and its minimum length is 1. The code for this option is 66, and its minimum length is 1.
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
Code Len TFTP server Code Len TFTP server
+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+---
| 66 | n | c1 | c2 | c3 | ... | 66 | n | c1 | c2 | c3 | ...
+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+---
9.5 Bootfile name 9.5 Bootfile name
This option is used to identify a bootfile when the 'file' field in the This option is used to identify a bootfile when the 'file' field in the
DHCP header has been used for DHCP options. DHCP header has been used for DHCP options.
skipping to change at page 29, line 5 skipping to change at page 29, line 5
5 DHCPACK 5 DHCPACK
6 DHCPNAK 6 DHCPNAK
7 DHCPRELEASE 7 DHCPRELEASE
8 DHCPINFORM 8 DHCPINFORM
Code Len Type Code Len Type
+-----+-----+-----+ +-----+-----+-----+
| 53 | 1 | 1-9 | | 53 | 1 | 1-9 |
+-----+-----+-----+ +-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
9.7. Server Identifier 9.7. Server Identifier
This option is used in DHCPOFFER and DHCPREQUEST messages, and may This option is used in DHCPOFFER and DHCPREQUEST messages, and may
optionally be included in the DHCPACK and DHCPNAK messages. DHCP optionally be included in the DHCPACK and DHCPNAK messages. DHCP
servers include this option in the DHCPOFFER in order to allow the servers include this option in the DHCPOFFER in order to allow the
client to distinguish between lease offers. DHCP clients indicate client to distinguish between lease offers. DHCP clients indicate
which of several lease offers is being accepted by including this which of several lease offers is being accepted by including this
option in a DHCPREQUEST message. option in a DHCPREQUEST message.
skipping to change at page 30, line 5 skipping to change at page 30, line 5
but MUST try to insert the requested options in the order requested but MUST try to insert the requested options in the order requested
by the client. by the client.
The code for this option is 55. Its minimum length is 1. The code for this option is 55. Its minimum length is 1.
Code Len Option Codes Code Len Option Codes
+-----+-----+-----+-----+--- +-----+-----+-----+-----+---
| 55 | n | c1 | c2 | ... | 55 | n | c1 | c2 | ...
+-----+-----+-----+-----+--- +-----+-----+-----+-----+---
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9.9. Message 9.9. Message
This option is used by a DHCP server to provide an error message to a This option is used by a DHCP server to provide an error message to a
DHCP client in a DHCPNAK message in the event of a failure. A client DHCP client in a DHCPNAK message in the event of a failure. A client
may use this option in a DHCPDECLINE message to indicate the why the may use this option in a DHCPDECLINE message to indicate the why the
client declined the offered parameters. The message consists of n client declined the offered parameters. The message consists of n
octets of NVT ASCII text, which the client may display on an octets of NVT ASCII text, which the client may display on an
available output device. available output device.
skipping to change at page 31, line 5 skipping to change at page 31, line 5
The value is in units of seconds, and is specified as a 32-bit The value is in units of seconds, and is specified as a 32-bit
unsigned integer. unsigned integer.
The code for this option is 58, and its length is 4. The code for this option is 58, and its length is 4.
Code Len T1 Interval Code Len T1 Interval
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 58 | 4 | t1 | t2 | t3 | t4 | | 58 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
9.12. Rebinding (T2) Time Value 9.12. Rebinding (T2) Time Value
This option specifies the time interval from address assignment until This option specifies the time interval from address assignment until
the client transitions to the REBINDING state. the client transitions to the REBINDING state.
The value is in units of seconds, and is specified as a 32-bit The value is in units of seconds, and is specified as a 32-bit
unsigned integer. unsigned integer.
The code for this option is 59, and its length is 4. The code for this option is 59, and its length is 4.
Code Len T2 Interval Code Len T2 Interval
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
| 59 | 4 | t1 | t2 | t3 | t4 | | 59 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+ +-----+-----+-----+-----+-----+-----+
9.13. Class-identifier 9.13. Vendor class identifier
This option is used by DHCP clients to optionally identify the type This option is used by DHCP clients to optionally identify the vendor
and configuration of a DHCP client. The information is a string of n type and configuration of a DHCP client. The information is a string
octets, interpreted by servers. Vendors and sites may choose to of n octets, interpreted by servers. Vendors may choose to define
define specific class identifiers to convey particular configuration specific vendor class identifiers to convey particular configuration
or other identification information about a client. For example, the or other identification information about a client. For example, the
identifier may encode the client's hardware configuration. Servers identifier may encode the client's hardware configuration. Servers
not equipped to interpret the class-specific information sent by a not equipped to interpret the class-specific information sent by a
client MUST ignore it (although it may be reported). client MUST ignore it (although it may be reported). Servers that
respond SHOULD only use option 43 to return the vendor-specific
information to the client.
The code for this option is 60, and its minimum length is 1. The code for this option is 60, and its minimum length is 1.
Code Len Class-Identifier Code Len Vendor class Identifier
+-----+-----+-----+-----+--- +-----+-----+-----+-----+---
| 60 | n | i1 | i2 | ... | 60 | n | i1 | i2 | ...
+-----+-----+-----+-----+--- +-----+-----+-----+-----+---
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995 DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
9.14. Client-identifier 9.14. Client-identifier
This option is used by DHCP clients to specify their unique This option is used by DHCP clients to specify their unique
identifier. DHCP servers use this value to index their database of identifier. DHCP servers use this value to index their database of
address bindings. This value is expected to be unique for all address bindings. This value is expected to be unique for all
clients in an administrative domain. clients in an administrative domain.
Identifiers consist of a type-value pair, similar to the Identifiers SHOULD be treated as opaque objects by DHCP servers.
'htype'/'chaddr' fields defined in [3].
It is expected that this field will typically contain a hardware type The client identifier MAY consist of type-value pairs similar to the
and hardware address, but this is not required. Current legal values 'htype'/'chaddr' fields defined in [3]. For instance, it MAY consist
for hardware types are defined in [22]. A hardware type of 0 of a hardware type and hardware address. In this case the type field
indicates that the identifier is not a hardware type (e.g., a fully SHOULD be one of the ARP hardware types defined in STD2 [22]. A
qualified domain name) and should be treated as an opaque object. hardware type of 0 (zero) should be used when the value field
contains an identifier other than a hardware address (e.g. a fully
qualified domain name).
The code for this option is 61, and its minimum length is 2. The code for this option is 61, and its minimum length is 2.
Code Len Type Client-Identifier Code Len Type Client-Identifier
+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+---
| 61 | n | t1 | i1 | i2 | ... | 61 | n | t1 | i1 | i2 | ...
+-----+-----+-----+-----+-----+--- +-----+-----+-----+-----+-----+---
9.15. User Class Information
This option is used by a DHCP client to optionally identify the type
or category of user or applications it represents. The information
contained in this option is an NVT ASCII text object that represents
the user class of which the client is a member.
DHCP administrators may define specific user class identifiers to
convey information about a client's software configuration or about
its user's preferences. For example, an identifier may specify that
a particular DHCP client is a member of the class "accounting
auditors", which have special service needs such as a particular
database server.
Servers not equipped to interpret any of user classes specified by a
client MUST ignore it (although it may be reported). Otherwise,
servers SHOULD respond with the set of options corresponding to the
user class specified by the client. Further, if the server responds,
it MUST return this option to the client.
Clients which do not receive information for the user class requested
SHOULD make an attempt to operate without it, although they may do so
(and may announce they are doing so) in a degraded mode.
DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
The code for this option is 77. The minimum length for this option
is two.
Code Len text1
+-----+-----+-----+-----+-----
| 77 | N | c1 | c2 | ...
+-----+-----+-----+-----+-----
10. Extensions 10. Extensions
Additional generic data fields may be registered by contacting: Additional generic data fields may be registered by contacting:
Internet Assigned Numbers Authority (IANA) Internet Assigned Numbers Authority (IANA)
USC/Information Sciences Institute USC/Information Sciences Institute
4676 Admiralty Way 4676 Admiralty Way
Marina del Rey, California 90292-6695 Marina del Rey, California 90292-6695
or by email as: iana@isi.edu or by email as: iana@isi.edu
skipping to change at page 33, line 5 skipping to change at page 33, line 41
The authors would like to thank Philip Almquist for his feedback on The authors would like to thank Philip Almquist for his feedback on
this document. The comments of the DHCP Working Group are also this document. The comments of the DHCP Working Group are also
gratefully acknowledged. In particular, Mike Carney and Jon Dreyer gratefully acknowledged. In particular, Mike Carney and Jon Dreyer
from SunSelect suggested the current format of the Vendor-specific from SunSelect suggested the current format of the Vendor-specific
Information option. Information option.
RFC 1497 is based on earlier work by Philip Prindeville, with help RFC 1497 is based on earlier work by Philip Prindeville, with help
from Drew Perkins, Bill Croft, and Steve Deering. from Drew Perkins, Bill Croft, and Steve Deering.
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995
12. References 12. References
[1] Droms, R., "Dynamic Host Configuration Protocol", RFC 1531, [1] Droms, R., "Dynamic Host Configuration Protocol", RFC 1531,
Bucknell University, October 1993. Bucknell University, October 1993.
[2] Reynolds, J., "BOOTP Vendor Information Extensions", RFC 1497, [2] Reynolds, J., "BOOTP Vendor Information Extensions", RFC 1497,
USC/Information Sciences Institute, August 1993. USC/Information Sciences Institute, August 1993.
[3] Croft, W., and J. Gilmore, "Bootstrap Protocol", RFC 951, [3] Croft, W., and J. Gilmore, "Bootstrap Protocol", RFC 951,
Stanford University and Sun Microsystems, September 1985. Stanford University and Sun Microsystems, September 1985.
[4] Braden, R., Editor, "Requirements for Internet Hosts - [4] Braden, R., Editor, "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122, USC/Information Sciences Communication Layers", STD 3, RFC 1122, USC/Information Sciences
DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
Institute, October 1989. Institute, October 1989.
[5] Mogul, J., and J. Postel, "Internet Standard Subnetting [5] Mogul, J., and J. Postel, "Internet Standard Subnetting
Procedure", STD 5, RFC 950, USC/Information Sciences Institute, Procedure", STD 5, RFC 950, USC/Information Sciences Institute,
August 1985. August 1985.
[6] Postel, J., and K. Harrenstien, "Time Protocol", STD 26, RFC [6] Postel, J., and K. Harrenstien, "Time Protocol", STD 26, RFC
868, USC/Information Sciences Institute, SRI, May 1983. 868, USC/Information Sciences Institute, SRI, May 1983.
[7] Postel, J., "Name Server", IEN 116, USC/Information Sciences [7] Postel, J., "Name Server", IEN 116, USC/Information Sciences
skipping to change at page 34, line 4 skipping to change at page 34, line 42
[12] Mogul, J. and S. Deering, "Path MTU Discovery", RFC 1191, [12] Mogul, J. and S. Deering, "Path MTU Discovery", RFC 1191,
DECWRL, Stanford University, November 1990. DECWRL, Stanford University, November 1990.
[13] Deering, S., "ICMP Router Discovery Messages", RFC 1256, [13] Deering, S., "ICMP Router Discovery Messages", RFC 1256,
Xerox PARC, September 1991. Xerox PARC, September 1991.
[14] Leffler, S. and M. Karels, "Trailer Encapsulations", RFC 893, [14] Leffler, S. and M. Karels, "Trailer Encapsulations", RFC 893,
U. C. Berkeley, April 1984. U. C. Berkeley, April 1984.
[15] Hornig, C., "Standard for the Transmission of IP Datagrams over [15] Hornig, C., "Standard for the Transmission of IP Datagrams over
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995
Ethernet Networks", RFC 894, Symbolics, April 1984. Ethernet Networks", RFC 894, Symbolics, April 1984.
[16] Postel, J. and J. Reynolds, "Standard for the Transmission of [16] Postel, J. and J. Reynolds, "Standard for the Transmission of
IP Datagrams Over IEEE 802 Networks", RFC 1042, USC/Information IP Datagrams Over IEEE 802 Networks", RFC 1042, USC/Information
Sciences Institute, February 1988. Sciences Institute, February 1988.
[17] Sun Microsystems, "System and Network Administration", March [17] Sun Microsystems, "System and Network Administration", March
1990. 1990.
[18] Mills, D., "Internet Time Synchronization: The Network Time [18] Mills, D., "Internet Time Synchronization: The Network Time
Protocol", RFC 1305, UDEL, March 1992. Protocol", RFC 1305, UDEL, March 1992.
[19] NetBIOS Working Group, "Protocol Standard for a NetBIOS Service [19] NetBIOS Working Group, "Protocol Standard for a NetBIOS Service
DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
on a TCP/UDP transport: Concepts and Methods", STD 19, RFC 1001, on a TCP/UDP transport: Concepts and Methods", STD 19, RFC 1001,
March 1987. March 1987.
[20] NetBIOS Working Group, "Protocol Standard for a NetBIOS Service [20] NetBIOS Working Group, "Protocol Standard for a NetBIOS Service
on a TCP/UDP transport: Detailed Specifications", STD 19, RFC on a TCP/UDP transport: Detailed Specifications", STD 19, RFC
1002, March 1987. 1002, March 1987.
[21] Scheifler, R., "FYI On the X Window System", FYI 6, RFC 1198, [21] Scheifler, R., "FYI On the X Window System", FYI 6, RFC 1198,
MIT Laboratory for Computer Science, January 1991. MIT Laboratory for Computer Science, January 1991.
[22] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC 1340, [22] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC 1700,
USC/Information Sciences Institute, July 1992. USC/Information Sciences Institute, July 1992.
13. Security Considerations 13. Security Considerations
Security issues are not discussed in this memo. Security issues are not discussed in this memo.
DRAFT DHCP Options and BOOTP Vendor Extensions May 1995
14. Authors' Addresses 14. Authors' Addresses
Steve Alexander Steve Alexander
Lachman Technology, Inc. Lachman Technology, Inc.
1901 North Naper Boulevard 1901 North Naper Boulevard
Naperville, IL 60563-8895 Naperville, IL 60563-8895
Phone: (708) 505-9555 x256 Phone: (708) 505-9555 x256
EMail: stevea@lachman.com EMail: stevea@lachman.com
Ralph Droms Ralph Droms
Computer Science Department Computer Science Department
323 Dana Engineering 323 Dana Engineering
Bucknell University Bucknell University
Lewisburg, PA 17837 Lewisburg, PA 17837
Phone: (717) 524-1145 Phone: (717) 524-1145
EMail: droms@bucknell.edu EMail: droms@bucknell.edu
DRAFT DHCP Options and BOOTP Vendor Extensions September 1995
A. Changes to draft-ietf-dhc-options-1533update-00.txt:
* Section 8.4 - changed to indicate vendor-specific information is
interpreted based on vendor class identifier.
* Section 9.13 - changed "Class-identifier" to "Vendor class
identifier"
* Added section 9.15 describing "User class identifier"
 End of changes. 

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