Product Documentation

SCPS Support

Dec 07, 2012

CloudBridge software supports the SCPS (Space Communications Protocol Standard) TCP variant. SCPS is widely used for satellite communication.

See http://www.scps.org for general SCPS information.

SCPS is a TCP variant used in satellite communication and similar applications. The appliance can accelerate SCPS connections if the SCPS option is selected on the Configuration: Tuning page.

The main practical difference between SCPS and the default appliance behavior is that SCPS-style "selective negative acknowledgements" (SNACKs) are used instead of standard selective acknowledgements (SACKs). These two methods of enhancing data retransmissions are mutually exclusive, so if the appliance on one end of the connection has SCPS enabled and one does not, retransmission performance suffers. This condition also causes an "SCPS Mode Mismatch" alert.

If you must mix SCPS-enabled appliances with non-SCPS-enabled appliances, deploy them in such a way that mismatches do not occur. You can either use IP-based service class rules or arrange the deployment so that each path has matching appliances.