RFC 2379 (rfc2379) - Page 2 of 8

RSVP over ATM Implementation Guidelines

RFC 2379        RSVP over ATM Implementation Guidelines      August 1998


   This document uses the same terms and assumption stated in [2].
   Additionally, 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 [5].

2. Implementation Recommendations

   This section provides implementation guidelines for implementation of
   RSVP over ATM.  Several recommendations are common for all, RSVP
   sessions, both unicast and multicast.  There are also recommendations
   that are unique to unicast and multicast session types.

2.1 RSVP Message VC Usage

   The general issues related to which VC should be used for RSVP
   messages is covered in [6]. It discussed several implementation
   options including: mixed control and data, single control VC per
   session,  single control VC multiplexed among sessions, and multiple
   VCs multiplexed among sessions.  QoS for control VCs was also
   discussed.  The general discussion is not repeated here and [6]
   should be reviewed for detailed information.

   RSVP over ATM implementations SHOULD send RSVP control (messages)
   over the best effort data path, see figure 1.  It is permissible to
   allow a user to override this behavior.  The stated approach
   minimizes VC requirements since the best effort data path will need
   to exist in order for RSVP sessions to be established and in order
   for RSVP reservations to be initiated.  The specific best effort
   paths that will be used by RSVP are: for unicast, the same VC used to
   reach the unicast destination; and for multicast, the same VC that is
   used for best effort traffic destined to the IP multicast group.
   Note that for multicast there may be another best effort VC that is
   used to carry session data traffic, i.e., for data that is both in
   the multicast group and matching a sessions protocol and port.
















Berger                   Best Current Practice