Unicast-Prefix-Based IPv4 Multicast Addresses
RFC 6034
|
| Document |
Type |
|
RFC - Proposed Standard
(October 2010; No errata)
|
|
Last updated |
|
2015-10-14
|
|
Stream |
|
IETF
|
|
Formats |
|
plain text
pdf
html
bibtex
|
|
Reviews |
|
|
| Stream |
WG state
|
|
(None)
|
|
Document shepherd |
|
No shepherd assigned
|
| IESG |
IESG state |
|
RFC 6034 (Proposed Standard)
|
|
Consensus Boilerplate |
|
Unknown
|
|
Telechat date |
|
|
|
Responsible AD |
|
Ron Bonica
|
|
Send notices to |
|
(None)
|
Internet Engineering Task Force (IETF) D. Thaler
Request for Comments: 6034 Microsoft
Category: Standards Track October 2010
ISSN: 2070-1721
Unicast-Prefix-Based IPv4 Multicast Addresses
Abstract
This specification defines an extension to the multicast addressing
architecture of the IP Version 4 protocol. The extension presented
in this document allows for unicast-prefix-based assignment of
multicast addresses. By delegating multicast addresses at the same
time as unicast prefixes, network operators will be able to identify
their multicast addresses without needing to run an inter-domain
allocation protocol.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6034.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Thaler Standards Track [Page 1]
RFC 6034 Uni-Prefix-Based IPv4 Multicast October 2010
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Address Space . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 4
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 5
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5
8.1. Normative References . . . . . . . . . . . . . . . . . . . 5
8.2. Informative References . . . . . . . . . . . . . . . . . . 5
1. Introduction
RFC 3180 [RFC3180] defines an allocation mechanism (called "GLOP") in
233/8 whereby an Autonomous System (AS) number is embedded in the
middle 16 bits of an IPv4 multicast address, resulting in 256
multicast addresses per AS. Advantages of this mechanism include the
ability to get multicast address space without an inter-domain
multicast address allocation protocol, and the ease of determining
the AS that was assigned the address for debugging and auditing
purposes.
Some disadvantages of GLOP include:
o RFC 4893 [RFC4893] expands the size of an AS number to 4 bytes,
and GLOP cannot work with 4-byte AS numbers.
o When an AS covers multiple sites or organizations, administration
of the multicast address space within an AS must be handled by
other mechanisms, such as manual administrative effort or the
Multicast Address Dynamic Client Allocation Protocol (MADCAP)
[RFC2730].
o During debugging, identifying the AS does not immediately identify
the correct organization when an AS covers multiple organizations.
o Only 256 addresses are automatically available per AS, and
obtaining any more requires administrative effort.
More recently, a mechanism [RFC3306] has been developed for IPv6 that
provides a multicast range to every IPv6 subnet, which is at a much
finer granularity than an AS. As a result, the first three
disadvantages above are avoided (and the last disadvantage does not
apply to IPv6 due to the extended size of the address space).
Thaler Standards Track [Page 2]
RFC 6034 Uni-Prefix-Based IPv4 Multicast October 2010
Another advantage of providing multicast space to a subnet, rather
than just to an entire AS, is that multicast address assignments
Show full document text