A reservation style is a set of options that is included in the reservation request.
One reservation style concerns how reservations requested by different senders within the same session are handled. This type of reservation style is handled in one of two ways: either create a distinct reservation for each sender in the session, or use a single reservation that is shared among all packets of the selected senders.
Another reservation style concerns how senders are selected. Again, there are two choices: an explicit list of all selected senders, or a wildcard that implies all senders in the session.
Reservation Attributes and Styles describes the relationship between reservation attributes and styles.
Sender Selection | Distinct Reservation Style | Shared Reservation Style |
---|---|---|
Explicit | Fixed filter (FF) | Shared explicit (SE) |
Wildcard | Not defined | Wildcard filter (WF) |
Fixed Filter: The fixed filter (FF) reservation style uses a distinct reservation and an explicit sender selection. This means that each resource reservation is for a specific sender. The session resources are not shared with other senders' packets. Because each reservation is identified with a single sender, a unique label is assigned by the endpoint to each sender (i.e., point-to-point LSP reservation).
Shared Explicit: The shared explicit (SE) reservation style uses a shared reservation and an explicit sender selection. This means that a single resource reservation is created that is shared by multiple senders. The endpoint may specify which senders are to be included for the reservation. Because different senders are explicitly listed in the RESV message, different labels may be assigned to each sender. Thus, multiple shared-resource LSPs to the same endpoint can be created (i.e., multipoint-to-point LSP reservation). The Extreme MPLS (Multiprotocol Label Switching) implementation requests SE reservation style when signaling RSVP-TE LSPs.
Wildcard: The wildcard (WF) reservation style uses the shared reservation and wildcard sender options. A wildcard reservation creates a single reservation that is shared by data flows from all upstream senders.
The Extreme MPLS implementation does not support WF reservation style.