Network Working Group Internet Engineering Task Force
Internet-Draft S. Alexander
INTERACTIVE Systems
R. Droms
Bucknell University
November 1992
DHCP Options and BOOTP Vendor Extensions
Status of this Memo
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Abstract
The Dynamic Host Configuration Protocol (DHCP) [1] provides a
framework for passing configuration information to hosts on a TCP/IP
network. Configuration parameters and other control information are
carried in tagged data items that are stored in the "options" field
of the DHCP message. The data items themselves are also called
"options."
This document specifies the current set of DHCP options. This
document will be periodically updated as new options are defined.
Each superseding document will include the entire current list of
valid options.
Table of Contents
1. DHCP Option Fields ........................................ 2
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2. RFC 1084 Vendor Extensions ................................ 2
3. IP Layer Parameters per Host .............................. 6
4. IP Layer Parameters per Interface ......................... 9
5. Link Layer Parameters per Interface ....................... 11
6. TCP Parameters ............................................ 12
7. DHCP Extensions ........................................... 13
8. Security Considerations ................................... 16
9. References ................................................ 16
10. Authors' Address .......................................... 17
1. DHCP Option Fields
DHCP options have the same format as the BOOTP "vendor extensions"
defined in RFC 1084 [2]. Options may be fixed length or variable
length. All options begin with a tag octet, which uniquely
identifies the option. Fixed length options without data consist of
only a tag octet. For fixed length options with data, the data
immediately follows the tag octet. For variable length options, a
length octet follows the tag octet. The length octet is followed by
length octets of data.
All multi-octet quantities are in network byte-order.
All of the "vendor extensions" defined in RFC 1084 are also DHCP
options.
Option codes 128 to 254 (decimal) are reserved for site-specific
options.
Except for the options in section 7, all options may be used with
either DHCP or BOOTP.
Many of these options may have default values specified in other
documents. In particular, RFC 1122 [3] specifies default values for
many aspects of IP and TCP behavior.
2. RFC 1084 Vendor Extensions
This section lists the vendor extensions as defined in RFC 1084.
They are defined here for completeness.
2.1. Pad Option
The pad option can be used to cause subsequent fields to align on
word boundaries. The code for the pad option is 0, and its length is
1 octet.
Code
+-----+
| 0 |
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+-----+
2.2. End Option
The end option marks the end of valid information in the vendor
field. Subsequent octets should be filled with pad options. The
code for the end option is 255, and its length is 1 octet.
Code
+-----+
| 255 |
+-----+
2.3. Subnet Mask
The subnet mask option specifies the local subnet mask as per RFC 950
[4]. The code for the subnet mask option is 1, and its length is 4
octets.
If both the subnet mask and the router option are specified in a DHCP
reply, the subnet mask option MUST be first.
Code Subnet Mask
+-----+-----+-----+-----+-----+
| 1 | m1 | m2 | m3 | m4 |
+-----+-----+-----+-----+-----+
2.4. Time Offset
The time offset field specifies the offset of the local subnet in
seconds from Coordinated Universal Time (UTC). The offset is
expressed as a signed 32-bit integer. The code for the time offset
option is 2, and its length is 4 octets.
Code Time Offset
+-----+-----+-----+-----+-----+
| 2 | n1 | n2 | n3 | n4 |
+-----+-----+-----+-----+-----+
2.5. Router Option
The router option specifies a list of IP addresses for routers on the
local subnet. If one of the routers is preferred, it SHOULD be
listed first. The code for the router option is 3. The minimum
length for the router option is 4 octets, and the length MUST always
be a multiple of 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 3 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
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+-----+-----+-----+-----+-----+-----+-----+-----+--
2.6. Time Server Option
The time server option specifies a list of RFC 868 [5] time servers
on the local subnet. If one of the servers is preferred, it SHOULD
be listed first. 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 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 4 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.7. Name Server Option
The name server option specifies a list of IEN 116 [6] name servers
on the local subnet. If one of the servers is preferred, it SHOULD
be listed first. 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 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 5 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.8. Domain Name Server Option
The domain name server option specifies a list of Domain Name System
(RFC 1035 [7]) name servers on the local subnet. If one of the
servers is preferred, it SHOULD be listed first. The code for the
domain name server option is 6. The minimum length for this option
is 4 octets, and the length MUST always be a multiple of 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 6 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.9. Log Server Option
The log server option specifies a list of MIT-LCS UDP log servers on
the local subnet. If one of the servers is preferred, it SHOULD be
listed first. 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.
Code Len Address 1 Address 2
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+-----+-----+-----+-----+-----+-----+-----+-----+--
| 7 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.10. Cookie Server Option
The cookie server option specifies a list of RFC 865 [8] cookie
servers on the local subnet. If one of the servers is preferred, it
SHOULD be listed first. 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.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 8 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.11. LPR Server Option
The LPR server option specifies a list of RFC 1179 [9] line printer
servers on the local subnet. If one of the servers is preferred, it
SHOULD be listed first. The code for the LPR server option is 9. The
minimum length for this option is 4 octets, and the length MUST
always be a multiple of 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 9 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.12. Impress Server Option
The Impress server option specifies a list of Imagen Impress servers
on the local subnet. If one of the servers is preferred, it SHOULD
be listed first. 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 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 10 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.13. Resource Location Server Option
This option specifies a list of RFC 887 [10] Resource Location
servers on the local subnet. If one of the servers is preferred, it
SHOULD be listed first. 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.
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Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 11 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.14. Host Name Option
This option specifies the name of the DHCP client. The name may or
may not be qualified with the local domain name. See RFC 1035 for
character set restrictions. The code for this option is 12, and its
minimum length is 1.
Code Len Host Name
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 12 | n | h1 | h2 | h3 | h4 | h5 | h6 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
2.15. Boot File Size Option
This option specifies the length in 512-octet blocks of the default
boot image for the DHCP client. The file length is specified as an
unsigned 16-bit integer. The code for this option is 13, and its
length is 2.
Code Len File Size
+-----+-----+-----+-----+
| 13 | 2 | l1 | l2 |
+-----+-----+-----+-----+
3. IP Layer Parameters per Host
This section details the options that affect the operation of the IP
layer on a per-host basis.
3.1. IP Forwarding Enable/Disable Option
This option specifies whether the DHCP client should configure its IP
layer for packet forwarding. A value of 0 means disable IP
forwarding, and a value of 1 means enable IP forwarding. The code
for this option is 20, and its length is 1.
Code Len Value
+-----+-----+-----+
| 20 | 1 | 0/1 |
+-----+-----+-----+
3.2. Non-Local Source Routing Enable/Disable Option
This option specifies whether the DHCP client should configure its IP
layer to allow forwarding of datagrams with non-local source routes.
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A value of 0 means disallow forwarding of such datagrams, and a value
of 1 means allow forwarding. The code for this option is 21, and its
length is 1.
Code Len Value
+-----+-----+-----+
| 21 | 1 | 0/1 |
+-----+-----+-----+
3.3. Policy Filter Option
This option specifies policy filters for non-local source routing.
The filters consist of a list of IP addresses and masks which specify
destination/mask pairs with which to filter incoming source routes.
See RFC 1009 [11] for details.
The code for this option is 22. The minimum length of this option is
8, and the length MUST be a multiple of 8.
Code Len Address 1 Mask 1
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| 22 | n | a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Address 2 Mask 2
+-----+-----+-----+-----+-----+-----+-----+-----+---
| a1 | a2 | a3 | a4 | m1 | m2 | m3 | m4 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+---
3.4. Maximum Datagram Reassembly Size
This option specifies the maximum size datagram that the client
should be prepared to reassemble. The size is specified as a 16-bit
unsigned integer.
The code for this option is 23, and its length is 2.
Code Len Size
+-----+-----+-----+-----+
| 23 | 2 | s1 | s2 |
+-----+-----+-----+-----+
3.5. Default IP Time-to-live
This option specifies the default time-to-live that the client should
use on outgoing datagrams. The TTL is specified as an octet with a
value between 1 and 255.
The code for this option is 24, and its length is 1.
Code Len TTL
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+-----+-----+-----+
| 24 | 1 | ttl |
+-----+-----+-----+
3.6. Path MTU Aging Timeout Option
This option specifies the timeout to use when aging Path MTU values
discovered by the mechanism defined in RFC 1191 [12]. The timeout is
specified as a 32-bit unsigned integer.
The code for this option is 25, and its length is 4.
Code Len Timeout
+-----+-----+-----+-----+-----+-----+
| 25 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+
3.7. Path MTU Plateau Table Option
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
a list of 16-bit unsigned integers, ordered from smallest to largest.
The minimum MTU value cannot be smaller than 68.
The code for this option is 26. Its minimum length is 2, and the
length MUST be a multiple of 2.
Code Len Size 1 Size 2
+-----+-----+-----+-----+-----+-----+---
| 26 | n | s1 | s2 | s1 | s2 | ...
+-----+-----+-----+-----+-----+-----+---
3.8. Network Information Service Domain Option
This option specifies the name of the client's NIS [13] domain. The
domain is formatted as a character string consisting of characters
from the NVT ASCII character set.
The code for this option is 56. Its minimum length is 1.
Code Len NIS Domain Name
+-----+-----+-----+-----+-----+-----+---
| 56 | n | n1 | n2 | n3 | s4 | ...
+-----+-----+-----+-----+-----+-----+---
3.9. Network Information Servers Option
This option specifies a list of IP addresses indicating NIS servers
on the local subnet. If one address is preferred, it SHOULD be
listed first.
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The code for this option is 57. Its minimum length is 4, and the
length MUST be a multiple of 4..
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 57 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
3.10. Network Time Protocol Servers Option
This option specifies a list of IP addresses indicating NTP [14]
servers on the local subnet. If one address is preferred, it SHOULD
be listed first.
The code for this option is 58. Its minimum length is 4, and the
length MUST be a multiple of 4.
Code Len Address 1 Address 2
+-----+-----+-----+-----+-----+-----+-----+-----+--
| 58 | n | a1 | a2 | a3 | a4 | a1 | a2 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+--
4. IP Layer Parameters per Interface
This section details the options that affect the operation of the IP
layer on a per-interface basis. It is expected that a DHCP client
can issue multiple requests, one per interface, in order to configure
interfaces with their specific parameters.
4.1. Interface MTU Option
This option specifies the MTU to use on this interface. The MTU is
specified as a 16-bit unsigned integer. The minimum legal value for
the MTU is 68.
The code for this option is 29, and its length is 2.
Code Len MTU
+-----+-----+-----+-----+
| 29 | 2 | m1 | m2 |
+-----+-----+-----+-----+
4.2. All Subnets are Local Option
This option specifies whether or not the client can treat all subnets
as having the local MTU. A value of 0 indicates that the client
should not treat subnets as being local for purposes of MTU
computation. A value of 1 means that the client may treat all
subnets as being local.
The code for this option is 30, and its length is 1.
Code Len Value
+-----+-----+-----+
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| 30 | 1 | 0/1 |
+-----+-----+-----+
4.3. Broadcast Address Option
This option specifies whether or not the host portion of the
broadcast address for this interface should be all ones or all
zeroes. A value of 0 indicates that the client should use zeroes
(e.g. 128.212.64.0). A value of 1 means that the client should use
ones (e.g. 128.212.64.255).
The code for this option is 31, and its length is 1.
Code Len Value
+-----+-----+-----+
| 31 | 1 | 0/1 |
+-----+-----+-----+
4.4. Perform Mask Discovery Option
This option specifies whether or not the client should perform subnet
mask discovery using ICMP. A value of 0 indicates that the client
should not perform mask discovery. A value of 1 means that the
client should perform mask discovery.
The code for this option is 32, and its length is 1.
Code Len Value
+-----+-----+-----+
| 32 | 1 | 0/1 |
+-----+-----+-----+
4.5. Mask Supplier Option
This option specifies whether or not the client should respond to
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
respond.
The code for this option is 33, and its length is 1.
Code Len Value
+-----+-----+-----+
| 33 | 1 | 0/1 |
+-----+-----+-----+
4.6. Perform Router Discovery Option
This option specifies whether or not the client should solicit
routers using the Router Discovery mechanism defined in RFC 1256
[15]. A value of 0 indicates that the client should not perform
router discovery. A value of 1 means that the client should perform
router discovery.
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The code for this option is 34, and its length is 1.
Code Len Value
+-----+-----+-----+
| 34 | 1 | 0/1 |
+-----+-----+-----+
4.7. Router Solicitation Address Option
This option specifies the address to which the client should transmit
router solicitation requests.
The code for this option is 35, and its length is 4.
Code Len Address
+-----+-----+-----+-----+-----+-----+
| 35 | 4 | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+
4.8. Static Route Option
This option specifies a list of static routes that the client should
install in its routing cache. The routes consist of a list of IP
address pairs. The first address is the destination address, and the
second address is the router to the destination.
The code for this option is 37. The minimum length of this option is
8, and the length MUST be a multiple of 8.
Code Len Destination 1 Router 1
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| 37 | n | d1 | d2 | d3 | d4 | r1 | r2 | r3 | r4 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Destination 2 Router 2
+-----+-----+-----+-----+-----+-----+-----+-----+---
| d1 | d2 | d3 | d4 | r1 | r2 | r3 | r4 | ...
+-----+-----+-----+-----+-----+-----+-----+-----+---
5. Link Layer Parameters per Interface
This section lists the options that affect the operation of the data
link layer on a per-interface basis.
5.1. Trailer Encapsulation Option
This option specifies whether or not the client should negotiate the
use of trailers [16] when using the ARP protocol. A value 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.
The code for this option is 38, and its length is 1.
Code Len Value
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+-----+-----+-----+
| 38 | 1 | 0/1 |
+-----+-----+-----+
5.2. ARP Cache Timeout Option
This option specifies the timeout in seconds for ARP cache entries.
The time is specified as a 32-bit unsigned integer.
The code for this option is 39, and its length is 4.
Code Len Time
+-----+-----+-----+-----+-----+-----+
| 39 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+
5.3. Ethernet Encapsulation Option
This option specifies whether or not the client should use Ethernet
Version 2 (RFC 894 [17]) or IEEE 802.3 (RFC 1042 [18]) encapsulation
if the interface is an Ethernet. A value of 0 indicates that the
client should use RFC 894 encapsulation. A value of 1 means that the
client should use RFC 1042 encapsulation.
The code for this option is 40, and its length is 1.
Code Len Value
+-----+-----+-----+
| 40 | 1 | 0/1 |
+-----+-----+-----+
6. TCP Parameters
This section lists the options that affect the operation of the TCP
layer on a per-interface basis.
6.1. TCP Default TTL Option
This option specifies the default TTL that the client should use when
sending TCP segments. The value is represented as an 8-bit unsigned
integer. The minimum value is 1.
The code for this option is 41, and its length is 1.
Code Len TTL
+-----+-----+-----+
| 41 | 1 | n |
+-----+-----+-----+
6.2. TCP Keepalive Interval Option
This option specifies the interval that the client TCP should wait
before sending a keepalive message on a TCP connection. The time is
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specified as a 32-bit unsigned integer. A value of zero indicates
that the client should not generate keepalive messages on connections
unless specifically requested by an application.
The code for this option is 42, and its length is 4.
Code Len Time
+-----+-----+-----+-----+-----+-----+
| 42 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+
6.3. TCP Keepalive Garbage Option
This option specifies the whether or not the client should send TCP
keepalive messages with a octet of garbage for compatibility with
older implementations. A value of 0 indicates that a garbage octet
should not be sent. A value of 1 indicates that a garbage octet
should be sent.
The code for this option is 43, and its length is 1.
Code Len Value
+-----+-----+-----+
| 43 | 1 | 0/1 |
+-----+-----+-----+
7. DHCP Extensions
This section details the options that are specific to DHCP.
7.1. Requested IP Address
This option is used in a client request (DHCPDISCOVER) to allow the
client to request that a particular IP address be assigned. In a
server reply (DHCPOFFER), this option indicates the IP address that
the server is willing to offer.
The code for this option is 46, and its length is 4.
Code Len Address
+-----+-----+-----+-----+-----+-----+
| 46 | 4 | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+
7.2. IP Address Lease Time
This option is used in a client request (DHCPDISCOVER or DHCPREQUEST)
to allow the client a lease time for the IP address. In a server
reply (DHCPOFFER), a DHCP server uses this option to specify the
lease time it is willing to offer.
The code for this option is 47, and its length is 4.
Code Len Lease Time
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+-----+-----+-----+-----+-----+-----+
| 47 | 4 | t1 | t2 | t3 | t4 |
+-----+-----+-----+-----+-----+-----+
7.3. Option Overload
This option is used to indicate that the DHCP "sname" or "file"
fields are being overloaded by using them to carry DHCP options. A
DHCP server inserts this option if the returned parameters will
exceed the usual space allotted for options.
If this option is present, the DHCP client interprets the specified
additional fields after it concludes interpretation of the standard
option fields.
The code for this option is 48, and its length is 1. Legal values
for this option are:
Value Meaning
----- --------
1 use the "file" field to hold options
2 use the "sname" field to hold options
3 use both fields to hold options
Code Len Value
+-----+-----+-----+
| 48 | 1 |1/2/3|
+-----+-----+-----+
7.4. DHCP Message Type
This option is used to convey the type of the DHCP message. The code
for this option is 51, and its length is 1. Legal values for this
option are:
Value Message Type
----- ------------
1 DHCPDISCOVER
2 DHCPOFFER
3 DHCPREQUEST
4 DHCPDECLINE
5 DHCPACK
6 DHCPNAK
7 DHCPRELEASE
Code Len Type
+-----+-----+-----+
| 51 | 1 | 1-7 |
+-----+-----+-----+
7.5. Lease Identifier Cookie
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This option is used by a DHCP server to indicate the unique
identifier for an address lease. The cookie is an opaque object of n
octets. The cookie is used by the client to identify the lease in
future protocol transactions.
The code for this option is 52.
Code Len Cookie Data
+-----+-----+-----+-----+---
| 52 | n | c1 | c2 | ...
+-----+-----+-----+-----+---
7.6. Server Identifier
This option is used by a DHCP client to indicate which of several
lease offers it is accepting. The identifier is the IP address of
the selected server.
The code for this option is 53, and its length is 4.
Code Len Address
+-----+-----+-----+-----+-----+-----+
| 53 | 4 | a1 | a2 | a3 | a4 |
+-----+-----+-----+-----+-----+-----+
7.7. Parameter Request Vector
This option is used by a DHCP client to request values for specified
configuration parameters. The options are specified as a 32-octet
bit vector, where each bit that is set indicates the the client is
requesting a parameter for that option. The order of bits in the
vector is big-endian within octets. This means that the bit for
parameter code 0 is the left-most bit of the first octet.
The code for this option is 54, and its length is 32.
Code Len Bit Vector
+-----+-----+-----+-----+---
| 54 | 32 | c1 | c2 | ... 30 more octets ...
+-----+-----+-----+-----+---
7.8. Parameter Request List
This option is used by a DHCP client to request values for specified
configuration parameters. The list of requested parameters is
specified as n octets, where each octet is a valid DHCP option code
as defined in this document. The client may order the option codes
as it desires. The DHCP server is not required to return the options
in the requested order.
The code for this option is 55.
Code Len Option Codes
+-----+-----+-----+-----+---
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| 55 | n | c1 | c2 | ...
+-----+-----+-----+-----+---
7.9. Message
This option is used by a DHCP server to provide an error message to a
DHCP client in the event of a failure. The message consists of n
octets of NVT ASCII text, which the client may display on an
available output device.
The code for this option is 59.
Code Len Text
+-----+-----+-----+-----+---
| 59 | n | c1 | c2 | ...
+-----+-----+-----+-----+---
7.10. Maximum DHCP Message Size
This option specifies the maximum length DHCP message that it is
willing to accept. The length is specified as an unsigned 16-bit
integer. The code for this option is 60, and its length is 2. The
minimum legal value is 267 octets (264 octets for the DHCP header + 3
octets for the DHCP message type).
Code Len Length
+-----+-----+-----+-----+
| 60 | 2 | l1 | l2 |
+-----+-----+-----+-----+
8. Security Considerations
Security considerations are not addressed in this memo.
9. References
[1] Droms, R., "Dynamic Host Configuration Protocol", Internet Draft,
August 1992.
[2] Reynolds, J.K., "BOOTP Vendor Information Extensions", RFC 1084,
December 1988.
[3] Braden, R.T., "Requirements for Internet Hosts - Communication
Layers", RFC 1122,November 1989.
[4]
Mogul, J., "Internet Standard Subnetting Procedure", RFC 950,
August 1985.
[5] Postel, J.B., and K. Harrenstien, "Time Protocol", RFC 868, May
1983.
[6] Postel, J.B., "Name Server", IEN 116, August 1979.
S. Alexander, R. Droms Expires June 1993 [Page 16]
Internet-Draft DHCP Options and BOOTP Vendor Extensions November 1992
[7] Mockapetris, P.V., "Domain Names - Implementation and
Specification", RFC 1035, November 1987.
[8] Postel, J.B., "Quote of the Day Protocol", RFC 865, May 1983.
[9] McLaughlin, L., "Line Printer Daemon Protocol", RFC 1179, August
1990.
[10] Accetta, M., "Resource Location Protocol", RFC 887, December
1983.
[11] Braden, R.T. and J.B. Postel, "Requirements for Internet
Gateways", RFC 1009, June 1987.
[12] Mogul, J. and S. Deering, "Path MTU Discovery", RFC 1191,
November 1990.
[13] Sun Microsystems, "System and Network Administration", March
1990.
[14] Mills, D.L., "Internet Time Synchronization: The Network Time
Protocol", RFC 1129,November 1989.
[15] Deering, S.E., "ICMP Router Discovery Messages", RFC 1256,
September 1991.
[16] Leffler, S. and M.J. Karels, "Trailer Encapsulations", RFC 893,
April 1984.
[17] Hornig, C, "Standard for the Transmission of IP Datagrams over
Ethernet Networks", RFC 894, April 1984.
[18] Postel, J.B. and J.K. Reynolds, "Standard for the Transmission of
IP Datagrams Over IEEE 802 Networks", RFC 1042, February 1988.
10. Authors' Address
Steve Alexander
INTERACTIVE Systems Corporation
1901 North Naper Boulevard
Naperville, IL 60563-8895
Phone: (708) 505-9100 x256
EMail: stevea@isc.com
Ralph Droms
Computer Science Department
323 Dana Engineering
Bucknell University
Lewisburg, PA 17837
S. Alexander, R. Droms Expires June 1993 [Page 17]
Internet-Draft DHCP Options and BOOTP Vendor Extensions November 1992
Phone: (717) 524-1145
EMail: droms@bucknell.edu
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