draft-ietf-dhc-vendor-03.txt   rfc3925.txt 
DHC Working Group J. Littlefield Network Working Group J. Littlefield
Internet-Draft Cisco Systems, Inc. Request for Comments: 3925 Cisco Systems, Inc.
Expires: December 21, 2004 June 21, 2004 Category: Standards Track October 2004
Vendor-Identifying Vendor Options for DHCPv4 Vendor-Identifying Vendor Options for
draft-ietf-dhc-vendor-03.txt Dynamic Host Configuration Protocol version 4 (DHCPv4)
Status of this Memo Status of this Memo
By submitting this Internet-Draft, I certify that any applicable This document specifies an Internet standards track protocol for the
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and any of which I become aware will be disclosed, in accordance with improvements. Please refer to the current edition of the "Internet
RFC 3668. Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
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Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2004).
Abstract Abstract
The DHCP options for Vendor Class and Vendor-Specific Information can The Dynamic Host Configuration Protocol (DHCP) options for Vendor
be limiting or ambiguous when a DHCP client represents multiple Class and Vendor-Specific Information can be limiting or ambiguous
vendors. This document defines two new options, modeled on the IPv6 when a DHCP client represents multiple vendors. This document
options for vendor class and vendor-specific information, which defines two new options, modeled on the IPv6 options for vendor class
contain Enterprise Numbers to remove ambiguity. and vendor-specific information, that contain Enterprise Numbers to
remove ambiguity.
Conventions used in this document
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].
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions Used in This Document. . . . . . . . . . . . 2
2. Supporting Multiple Vendor Instances . . . . . . . . . . . . . 3 2. Supporting Multiple Vendor Instances . . . . . . . . . . . . . 3
3. Vendor-Identifying Vendor Class Option . . . . . . . . . . . . 4 3. Vendor-Identifying Vendor Class Option . . . . . . . . . . . . 3
4. Vendor-Identifying Vendor-Specific Information Option . . . . 5 4. Vendor-Identifying Vendor-Specific Information Option . . . . 5
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
6. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. Security Considerations . . . . . . . . . . . . . . . . . . . 7
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.1 Normative References . . . . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 8
7.2 Informative References . . . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . 9 8. Author's Address . . . . . . . . . . . . . . . . . . . . . . . 8
Intellectual Property and Copyright Statements . . . . . . . . 10 9. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
The DHCP protocol for IPv4, RFC 2131 [2], defines options that allow The DHCP protocol for IPv4, RFC 2131 [2], defines options that allow
a client to indicate its vendor type (option 60), and to allow the a client to indicate its vendor type (option 60), and the DHCP client
DHCP client and server to exchange vendor-specific information and server to exchange vendor-specific information (option 43) [5].
(option 43) [5]. While there is no prohibition against passing Although there is no prohibition against passing multiple copies of
multiple copies of these options in a single packet, doing so would these options in a single packet, doing so would introduce ambiguity
introduce ambiguity of interpretation, particularly if conveying of interpretation, particularly if conveying vendor-specific
vendor-specific information for multiple vendors. The vendor information for multiple vendors. The vendor identified by option 60
identified by option 60 defines the interpretation of option 43, defines the interpretation of option 43, which itself carries no
which itself carries no vendor identifier. Furthermore, the vendor identifier. Furthermore, the concatenation of multiple
concatenation of multiple instances of the same option, required by instances of the same option, required by RFC 2131 and specified by
RFC 2131 and specified by RFC 3396 [4], means that multiple copies of RFC 3396 [4], means that multiple copies of options 60 or 43 would
options 60 or 43 would not remain independent. not remain independent.
There are circumstances where an implementation may need to support In some circumstances, an implementation may need to support
multiple, independently defined forms of vendor-specific information. multiple, independently defined forms of vendor-specific information.
For example, implementations that must conform to an industry- For example, implementations that must conform to an industry-
standard use of DHCPv4, to allow interoperability in a particular standard use of DHCPv4, to allow interoperability in a particular
technology space, may be required to support the vendor-specific technology space, may be required to support the vendor-specific
options of that industry group. But the same implementation may also options of that industry group. But the same implementation may also
require support for vendor-specific options defined by the require support for vendor-specific options defined by the
manufacturer. In particular, this is an issue for vendors of devices manufacturer. In particular, this is an issue for vendors of devices
supporting CableLabs [9] standards, such as DOCSIS, CableHome, and supporting CableLabs [9] standards, such as DOCSIS, CableHome, and
PacketCable, since those standards define an industry-specific use PacketCable, as those standards define an industry-specific use for
for options 60 and 43. options 60 and 43.
This document defines two new options, modeled on the IPv6 options This document defines two new options, modeled on the IPv6 options
for vendor class and vendor-specific information defined in RFC 3315 for vendor class and vendor-specific information defined in RFC 3315
[6], which contain IANA-assigned Enterprise Numbers [3] to remove [6], that contain IANA-assigned Enterprise Numbers [3] to remove
ambiguity about the interpretation of their contents. If desired, ambiguity about the interpretation of their contents. If desired,
these new options can be used in addition to the current vendor class these new options can be used in addition to the current vendor class
and vendor information options, whose definition is unaffected by and vendor information options, whose definition is unaffected by
this document. this document.
1.1. Conventions Used in This Document
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 BCP 14, RFC 2119 [1].
2. Supporting Multiple Vendor Instances 2. Supporting Multiple Vendor Instances
The options defined in this document may each contain data The options defined in this document may each contain data
corresponding to more than one vendor. The data portion of each corresponding to more than one vendor. The data portion of each
option defined here contains an enterprise number (assigned by IANA option defined here contains an enterprise number (assigned by IANA
[3]), followed by an internal data length, followed by [3]), followed by an internal data length, followed by vendor-
vendor-specific data. This sequence may be repeated multiple times specific data. This sequence may be repeated multiple times within
within each option. Because of the possibility that the aggregate of each option. Because the aggregate of the vendor-specific data for
the vendor-specific data for either option will exceed 255 octets, either option may exceed 255 octets, these options are hereby
these options are hereby declared to be "concatenation-requiring", as declared to be "concatenation-requiring", as defined by RFC 3396 [4].
defined by RFC 3396 [4]. As such, the aggregate of all instances of As such, for each of the two options defined here, the aggregate of
vendor-specific data is to be considered one long option, for each of all instances of vendor-specific data is to be considered one long
the two options defined here. These long options can be divided into option. These long options can be divided into smaller options for
smaller options for packet encoding in conformance with RFC 3396, on packet encoding in conformance with RFC 3396, on whatever octet
whatever octet boundaries are convenient to the implementation. boundaries are convenient to the implementation. Dividing on the
Dividing on the boundaries between vendor instances is not required, boundaries between vendor instances is not required but may be
but may be convenient for encoding or packet tracing. convenient for encoding or packet tracing.
3. Vendor-Identifying Vendor Class Option 3. Vendor-Identifying Vendor Class Option
A DHCP client may use this option to unambiguously identify the A DHCP client may use this option to unambiguously identify the
vendor that manufactured the hardware on which the client is running, vendor that manufactured the hardware on which the client is running,
the software in use, or an industry consortium to which the vendor the software in use, or an industry consortium to which the vendor
belongs. The information contained in the per-vendor data area of belongs. The information contained in the per-vendor data area of
this option is contained in one or more opaque fields that may this option is contained in one or more opaque fields that may
identify details of the hardware configuration. identify details of the hardware configuration.
This option may be used wherever Vendor Class Identifier (option 60) This option may be used wherever Vendor Class Identifier (option 60)
may be used, as described in RFC 2131 [2], except for DHCPNAK may be used, as described in RFC 2131 [2], except for DHCPNAK
messages, where other options are not permitted. It is most messages, where other options are not permitted. It is most
meaningful in messages from DHCP client to DHCP server (DHCPDISCOVER, meaningful in messages from DHCP client to DHCP server (DHCPDISCOVER,
DHCPREQUEST, DHCPINFORM). DHCPREQUEST, DHCPINFORM).
The format of the V-I Vendor Class option is: The format of the V-I Vendor Class option is as follows:
1 1 1 1 1 1 1 1 1 1 1 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| option-code | option-len | | option-code | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| enterprise-number1 | | enterprise-number1 |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| data-len1 | | | data-len1 | |
skipping to change at page 5, line 4 skipping to change at page 4, line 28
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ---- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ----
| enterprise-number2 | ^ | enterprise-number2 | ^
| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| data-len2 | | optional | data-len2 | | optional
+-+-+-+-+-+-+-+-+ | | +-+-+-+-+-+-+-+-+ | |
/ vendor-class-data2 / | / vendor-class-data2 / |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
~ ... ~ V ~ ... ~ V
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ---- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ----
option-code OPTION_V-I_VENDOR_CLASS (to be assigned by IANA)
option-code OPTION_V-I_VENDOR_CLASS (124)
option-len total length of all following option data in option-len total length of all following option data in
octets octets
enterprise-numberN The vendor's 32-bit Enterprise Number as enterprise-numberN The vendor's 32-bit Enterprise Number as
registered with IANA [3] registered with IANA [3]
data-lenN Length of vendor-class-data field data-lenN Length of vendor-class-data field
vendor-class-dataN Details of the hardware configuration of the vendor-class-dataN Details of the hardware configuration of the
host on which the client is running, or of host on which the client is running, or of
industry consortium compliance industry consortium compliance
This option contains information corresponding to one or more This option contains information corresponding to one or more
Enterprise Numbers. Multiple instances of this option may be Enterprise Numbers. Multiple instances of this option may be present
present, and MUST be concatenated in accordance with RFC 3396 [4]. and MUST be concatenated in accordance with RFC 3396 [4]. An
An Enterprise Number SHOULD only occur once among all instances of Enterprise Number SHOULD only occur once among all instances of this
this option. Behavior is undefined if an Enterprise Number occurs option. Behavior is undefined if an Enterprise Number occurs
multiple times. The information for each Enterprise Number is multiple times. The information for each Enterprise Number is
treated independently, regardless or whether it occurs in an option treated independently, regardless or whether it occurs in an option
with other Enterprise Numbers, or in a separate option. with other Enterprise Numbers or in a separate option.
The vendor-class-data is composed of a series of separate items, each The vendor-class-data comprises a series of separate items, each of
of which describes some characteristic of the client's hardware which describes some characteristic of the client's hardware
configuration or capabilities. Examples of vendor-class-data configuration or capabilities. Examples of vendor-class-data
instances might include the version of the operating system the instances might include the version of the operating system the
client is running or the amount of memory installed on the client. client is running or the amount of memory installed on the client.
Each instance of the vendor-class-data is formatted as follows: Each instance of the vendor-class-data is formatted as follows:
1 1 1 1 1 1 1 1 1 1 1 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| data-len | | | data-len | |
skipping to change at page 5, line 50 skipping to change at page 5, line 28
/ / / /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The data-len is one octet long and specifies the length of the opaque The data-len is one octet long and specifies the length of the opaque
vendor class data in network byte order. vendor class data in network byte order.
4. Vendor-Identifying Vendor-Specific Information Option 4. Vendor-Identifying Vendor-Specific Information Option
DHCP clients and servers may use this option to exchange vendor- DHCP clients and servers may use this option to exchange vendor-
specific information. Either party may send this option, as needed. specific information. Either party may send this option, as needed.
While a typical case might be for a client to send the Although a typical case might be for a client to send the Vendor-
Vendor-Identifying Vendor Class option, to elicit a useful Identifying Vendor Class option, to elicit a useful Vendor-
Vendor-Identifying Vendor-Specific Information Option, there is no Identifying Vendor-Specific Information Option, there is no
requirement for such a flow. requirement for such a flow.
This option may be used in any packets where "other" options are This option may be used in any packets where "other" options are
allowed by RFC2131 [2], specifically DHCPDISCOVER, DHCPOFFER, allowed by RFC2131 [2], specifically DHCPDISCOVER, DHCPOFFER,
DHCPREQUEST, DHCPACK and DHCPINFORM. DHCPREQUEST, DHCPACK, and DHCPINFORM.
The format of the V-I Vendor-specific Information option is: The format of the V-I Vendor-specific Information option is as
follows:
1 1 1 1 1 1 1 1 1 1 1 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| option-code | option-len | | option-code | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| enterprise-number1 | | enterprise-number1 |
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| data-len1 | | | data-len1 | |
skipping to change at page 6, line 35 skipping to change at page 6, line 30
| enterprise-number2 | ^ | enterprise-number2 | ^
| | | | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| data-len2 | | optional | data-len2 | | optional
+-+-+-+-+-+-+-+-+ option-data2 | | +-+-+-+-+-+-+-+-+ option-data2 | |
/ / | / / |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
~ ... ~ V ~ ... ~ V
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ---- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ----
option-code OPTION_V-I_VENDOR_OPTS (to be assigned by IANA) option-code OPTION_V-I_VENDOR_OPTS (125)
option-len total length of all following option data in option-len total length of all following option data in
octets octets
enterprise-numberN The vendor's registered 32-bit Enterprise Number enterprise-numberN The vendor's registered 32-bit Enterprise Number
as registered with IANA [3] as registered with IANA [3]
data-lenN Length of option-data field data-lenN Length of option-data field
option-dataN Vendor-specific options, described below. option-dataN Vendor-specific options, described below
The definition of the information carried in this option is vendor The definition of the information carried in this option is vendor
specific. The vendor is indicated in the enterprise-number field. specific. The vendor is indicated in the enterprise-number field.
This option contains information corresponding to one or more This option contains information corresponding to one or more
Enterprise Numbers. Multiple instances of this option may be Enterprise Numbers. Multiple instances of this option may be present
present, and MUST be concatenated in accordance with RFC 3396 [4]. and MUST be concatenated in accordance with RFC 3396 [4].
An Enterprise Number SHOULD only occur once among all instances of An Enterprise Number SHOULD only occur once among all instances of
this option. Behavior is undefined if an Enterprise Number occurs this option. Behavior is undefined if an Enterprise Number occurs
multiple times. The information for each Enterprise Number is multiple times. The information for each Enterprise Number is
treated independently, regardless or whether it occurs in an option treated independently, regardless or whether it occurs in an option
with other Enterprise Numbers, or in a separate option. with other Enterprise Numbers, or in a separate option.
Use of vendor-specific information allows enhanced operation, Use of vendor-specific information allows enhanced operation,
utilizing additional features in a vendor's DHCP implementation. utilizing additional features in a vendor's DHCP implementation.
Servers not equipped to interpret the vendor-specific information Servers not equipped to interpret the vendor-specific information
skipping to change at page 7, line 45 skipping to change at page 7, line 39
subopt-len An unsigned integer giving the length of the subopt-len An unsigned integer giving the length of the
option-data field in this encapsulated option in option-data field in this encapsulated option in
octets octets
sub-option-data Data area for the encapsulated option sub-option-data Data area for the encapsulated option
5. IANA Considerations 5. IANA Considerations
The values for the OPTION_V-I_VENDOR_CLASS and OPTION_V-I_VENDOR_OPTS The values for the OPTION_V-I_VENDOR_CLASS and OPTION_V-I_VENDOR_OPTS
option codes must be assigned from the numbering space defined for option codes have been assigned from the numbering space defined for
public DHCP Options in RFC 2939 [7]. public DHCP Options in RFC 2939 [7].
6. Security Considerations 6. Security Considerations
This document in and by itself provides no security, nor does it This document in and by itself provides no security, nor does it
impact existing security. DHCP provides an authentication and impact existing security. DHCP provides an authentication and
message integrity mechanism, as described in RFC 3118 [8], which may message integrity mechanism, as described in RFC 3118 [8], which may
be used if authenticity is required for data carried by the options be used if authenticity is required for data carried by the options
defined in this document. defined in this document.
7. References 7. References
7.1 Normative References 7.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[2] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, [2] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131,
March 1997. March 1997.
[3] IANA, "Private Enterprise Numbers", [3] IANA, "Private Enterprise Numbers",
<http://www.iana.org/assignments/enterprise-numbers.html>. <http://www.iana.org/assignments/enterprise-numbers>.
[4] Lemon, T. and S. Chesire, "Encoding Long Options in the Dynamic [4] Lemon, T. and S. Cheshire, "Encoding Long Options in the Dynamic
Host Configuration Protocol (DHCPv4)", RFC 3396, November 2002. Host Configuration Protocol (DHCPv4)", RFC 3396, November 2002.
7.2 Informative References 7.2. Informative References
[5] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor [5] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
Extensions", RFC 2132, March 1997. Extensions", RFC 2132, March 1997.
[6] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C. and M. [6] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M.
Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)",
RFC 3315, July 2003. RFC 3315, July 2003.
[7] Droms, R., "Procedures and IANA Guidelines for Definition of New [7] Droms, R., "Procedures and IANA Guidelines for Definition of New
DHCP Options and Message Types", BCP 43, RFC 2939, September DHCP Options and Message Types", BCP 43, RFC 2939, September
2000. 2000.
[8] Droms, R. and W. Arbaugh, "Authentication for DHCP Message", RFC [8] Droms, R. and W. Arbaugh, "Authentication for DHCP Messages",
3118, June 2001. RFC 3118, June 2001.
URIs URIs
[9] <http://www.cablelabs.com/> [9] <http://www.cablelabs.com/>
Author's Address 8. Author's Address
Josh Littlefield Josh Littlefield
Cisco Systems, Inc. Cisco Systems, Inc.
1414 Massachusetts Avenue 1414 Massachusetts Avenue
Boxborough, MA 01719 Boxborough, MA 01719
USA USA
Phone: +1 978-936-1379 Phone: +1 978-936-1379
EMail: joshl@cisco.com EMail: joshl@cisco.com
Intellectual Property Statement 9. Full Copyright Statement
Copyright (C) The Internet Society (2004).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE 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.
Intellectual Property
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights this document or the extent to which any license under such rights
might or might not be available; nor does it represent that it has might or might not be available; nor does it represent that it has
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The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
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This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE 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.
Copyright Statement
Copyright (C) The Internet Society (2004). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
Acknowledgment Acknowledgement
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is currently provided by the
Internet Society. Internet Society.
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