Reservation Styles in Resource Reservation Protocol (RSVP) (247112)

SUMMARY

Resource Reservation Protocol (RSVP) uses filter styles in defining how Quality of Service (QoS) traffic is treated on QoS devices throughout the network. The filter styles are: Fixed, Wildcard, and Shared Explicit. These filter styles are carried across the network in RSVP messages as (FF)-Fixed Filter, (WF)-Wildcard Filter, and (SE)-Shared Explicit Filter.

MORE INFORMATION

Fixed filter: This filter style always indicates a distinct reservation and an explicit sender. Each of the filter types has its own fixed unshared transmission characteristics. Fixed Filter is used for unicast sessions, and only uses TCP.
Wildcard filter: When you use Wildcard filters, all connections associated with the flow share the same flow characteristics; the receiver is part of a shared transmission. Wildcard filters are appropriate for multicast sessions. When you are using the multicast techniques, send one packet and have it propagate to all participating recipients, rather than sending an identical packet multiple times.
Shared Explicit filter: Shared Explicit is somewhat similar to Fixed filter and Wildcard filter in that it is shared, but it is explicit. The Shared Explicit filter allows a receiver to share a flow with (explicitly) selected senders. This filter style is unusual; it is not used by default. Using this filter style requires direct programming of RSVP through the RSVP_RESERVE_INFO object.

The QoS service provider invokes RSVP while using the information in the program; it decides what filter style it wants to use based on the program's flow specification. It then tells RSVP to apply that filter to the message it transmits across the network.