rfc2996.txt

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5. References

   [INTDIFF]  Bernet, Y., Yavatkar, R., Ford, P., Baker, F., Zhang, L.,
              Speer, M., Braden, R., Davie, B. and J. Wroclawski, "A
              Framework for Integrated Services Operation over Diffserv
              Networks", RFC 2998, November 2000.

   [DS]       Blake, S., Carlson, M., Davies, D., Wang, Z. and W. Weiss,
              "An Architecture for Differentiated Services", RFC 2475,
              December 1998.

   [RSVP]     Braden, R., Zhang, L., Berson, S., Herzog, S. and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, September 1997.

   [RAP]      Yavatkar, R., Pendarakis, D. and R. Guerin,  "A Framework
              for Policy Based Admission Control", RFC 2753, January
              2000.

   [AF]       Heinanen, J., Baker, F., Weiss, W. and J. Wroclawski,
              "Assured Forwarding PHB Group", RFC 2597, June 1999.





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6. Acknowledgments

   Thanks to Fred Baker and Carol Iturralde for reviewing this document.
   Thanks to Ramesh Pabbati, Tim Moore, Bruce Davie and Kam Lee for
   input.

7. Author's Address

   Yoram Bernet
   Microsoft
   One Microsoft Way,
   Redmond, WA 98052

   Phone: [phone]
   EMail: [e-mail]




































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Appendix A - Simple Configurable Resource Based Admission Control

   Routers may use quite sophisticated mechanisms in making the
   admission control decision, including policy considerations, various
   intra-domain signaling protocols, results of traffic monitoring and
   so on.  It is recommended that the following basic functionality be
   provided to enable simple resource based admission control in the
   absence of more sophisticated mechanisms.  This functionality can be
   used with configurable, standalone routers.  It applies to standard
   RSVP/Intserv requests.  This minimal functionality assumes only a
   single DSCP is included in the DCLASS object, but may readily be
   extended to support multiple DSCPs.

   It must be possible to configure two tables in the router.  These are
   described below.

A.1 Service Type to DSCP Mapping

   One table provides a mapping from the intserv service-type specified
   in the RSVP request to a DSCP that can be used to obtain a
   corresponding service in the diff-serv network.  This table contains
   a row for each intserv service type for which a mapping is available.
   Each row has the following format:

      Intserv service type : DSCP

   The table would typically contain at least three rows; one for
   Guaranteed service, one for Controlled Load service and one for Best-
   Effort service.  (The best-effort service will typically map to DSCP
   000000, but may be overridden).  It should be possible to add rows
   for as-yet-undefined service types.

   This table allows the network administrator to statically configure a
   DSCP that the router will return in the DCLASS object for an admitted
   RSVP request.  In general, more sophisticated and likely more dynamic
   mechanisms may be used to determine the DSCP to be returned in the
   DCLASS object.  Also, it is likely that a real mapping for some
   services would use more than one DSCP, with the DSCP depending on the
   invocation parameters of a specific service request.  In this case,
   these mechanisms may override or replace the static table based
   mapping described here.

A.2 Quantitative Resource Availability

   Standard intserv requests are quantitative in nature.  They include
   token bucket parameters describing the resources required by the
   traffic for which admission is requested.  The second table enables
   the network administrator to statically configure quantitative



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   parameters to be used by the router when making an admission control
   decision for quantitative service requests.  Each row in this table
   has the following form:

      DSCP : Token bucket profile

   The first column specifies those DSCPs for which quantitative
   admission control is applied.  The second column specifies the token
   bucket parameters which represent the total resources available in
   the diff-serv network to accommodate traffic in the service class
   specified by the DSCP.








































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Full Copyright Statement

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
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   The limited permissions granted above are perpetual and will not be
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Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.



















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