Understanding Central Point Architecture Support for SCTP
As we know that the SCTP association is a connection between two SCTP endpoints. Each endpoint identifies it’s association with a tag. During it’s setup the SCTP endpoints exchange their tags for receiving packets. So during the exchange f packets between two SCTP endpoints the both source and destination address can change in the association life cycle.
Before the release of Junos OS 15.1X49-D40 all the sessions of the SCTP association are hashed to the same SPU with the help of the fixed per association SCTP port pair. In many of the cases multiple SCTP association use the same port pair, which results a bad load balancing with all the traffic handled by single SPU. When the version Junos OS release 15.1X49-D40 and Junos OS Release 17.3R1 to handle load balancing issue, the tag based hash distribution is used to ensure the even distribution of the traffic of SCTP from various associations among all the SPU’s. It’s flow session utilizes a connection tag to more finely distribute SCTP traffic across all the SPU’s on the SRX1500, SRX4100, SRX4200, SRX5400, SRX600, and SRX800 devices that supports the SCTP ALG. The decoding of connection tag is from SCTP vtag.
Stream Control Transmission Protocol (SCTP)
Stream Control Transmission Protocol (SCTP) is a network protocol that is connection-oriented and used for transmitting multiple streams of data simultaneously between any two endpoints that have established a connection in a computer network. SCTP is a transport layer of Internet Protocol (IP).
SCTP support telephone connection over the internet.