Clients sometimes need to reserve a specific amount of
bandwidth for a presentation. The existing Bandwidth:
header is defined to be an advisory estimate sent from
server to client, and is not really suitable for what
is really part of a Transport: negotiation. This can
be addressed by adding a new Transport parameter.
A client may use the "bandwidth" Transport parameter to
reserve bandwidth for a transport. Its argument is a
decimal number specifying the bandwidth to reserve in
bits per second. If no bandwidth parameter is given,
it implies that the media server will use the bit rate
of the presentation specified in the SETUP request's
URI for the bandwidth of the transport.
The formal syntax for the "bandwidth" parameter is:
bandwidth = "bandwidth" "=" 1*DIGIT
I think its more than an advisory it tells you that the server can't send more then that header indicated for your session.
If you send a value and the server honors it then it will fulfill it.
Whats advisory about that and what else is required?
I don't think this considers Scale and other possible attributes which may also be in use.
Also if this means on a per stream basis the that is a sdp definition.