Extensible Bandwidth Attribute for SDP

Document Type Expired Internet-Draft (individual)
Authors Tomas Frankkila  , Magnus Westerlund  , Bo Burman 
Last updated 2013-01-17 (latest revision 2012-07-16)
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Knowledge of what bandwidths the end-points intend to use is important both for the other end-point and for resource allocation in various types of networks. This is especially important for wireless access networks which typically have quite limited resources. The bandwidth attribute in Session Description Protocol (SDP), 'b=AS', is today quite widely used to define the bandwidth that the end-points intends to use, in various types of sessions. This document will show that the existing bandwidth attribute, such as 'b=AS', although widely used in today's scenarios, has limitations that make it hard or even impossible for the end-points to express their intentions accurately when it comes to bandwidth usage. To solve the identified problems, this document defines a new extensible SDP bandwidth attribute 'a=bw' which enables more detailed control over the bandwidth declarations, request, and allocations. With the new bandwidth attribute it is possible to define different scopes in the session setup and then negotiate the bandwidth individually for each scope.


Tomas Frankkila (tomas.frankkila@ericsson.com)
Magnus Westerlund (magnus.westerlund@ericsson.com)
Bo Burman (bo.burman@ericsson.com)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)