Network Working Group S. Hanna
Requests for Comments: 2730 Sun Microsystems, Inc.
Category: Standards Track B. Patel
Multicast Address Dynamic Client Allocation Protocol (MADCAP)
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (1999). All Rights Reserved.
This document defines a protocol, Multicast Address Dynamic Client
Allocation Protocol (MADCAP), that allows hosts to request multicast
addresses from multicast address allocation servers.
Multicast Address Dynamic Client Allocation Protocol (MADCAP) is a
protocol that allows hosts to request multicast address allocation
services from multicast address allocation servers. This protocol is
part of the Multicast Address Allocation Architecture being defined
by the IETF Multicast Address Allocation Working Group. However, it
may be used separately from the rest of that architecture as
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 .
Constants used by this protocol are shown as [NAME-OF-CONSTANT], and
summarized in Appendix B.
Hanna, et al. Standards Track [Page 1]
RFC 2730 MADCAP December 1999
This specification uses a number of terms that may not be familiar to
the reader. This section defines some of these and refers to other
documents for definitions of others.
MADCAP client or client
A host requesting multicast address allocation services via MADCAP.
MADCAP server or server
A host providing multicast address allocation services via MADCAP.
IP Multicast, as defined in  and modified in .
An IP multicast address or group address, as defined in  and
. An identifier for a group of nodes.
A range of multicast addresses configured so that traffic sent to
these addresses is limited to some subset of the internetwork. See
 and .
The lowest numbered address in a multicast scope. This definition
applies only within this document.
One multicast scope may have several instances, which are known as
Scope Zones or zones, for short.
For instance, an organization may have multiple sites. Each site
might have its own site-local Scope Zone, each of which would be an
instance of the site-local Scope. However, a given interface on a
given host would only ever be in at most one instance of a given
scope. Messages sent by a host in a site-local Scope Zones to an
address in the site-local Scope would be limited to the site-local
Scope Zone containing the host.
A human readable name for a Scope Zone. An ISO 10646 character
string with an RFC 1766  language tag. One zone may have several
zone names, each in a different language. For instance, a zone for
use within IBM's locations in Switzerland might have the names "IBM
Suisse", "IBM Switzerland", "IBM Schweiz", and "IBM Svizzera" with
language tags "fr", "en", "de", and "it".
Hanna, et al. Standards Track [Page 2]
RFC 2730 MADCAP December 1999
Multicast Scope List
A list of multicast scope zones.
Since it can be difficult to determine which multicast scope zones
are in effect, MADCAP clients can ask MADCAP servers to supply a
Multicast Scope List listing all of the zones available to the
client. For each scope zone, the list includes the range of