SCTP Packets

SCTP packets consist of a common header and one or more chunks, each of which serves a specific purpose.

• DATA chunk — carries user data
• INIT chunk — initiates an association between SCTP endpoints
• INIT ACK chunk — acknowledges association establishment
• SACK chunk — acknowledges received DATA chunks and informs the peer endpoint of gaps in the received subsequences of DATA chunks
• HEARTBEAT chunk — tests the reachability of an SCTP endpoint
• HEARTBEAT ACK chunk — acknowledges reception of a HEARTBEAT chunk
• ABORT chunk — forces an immediate close of an association
• SHUTDOWN chunk — initiates a graceful close of an association
• SHUTDOWN ACK chunk — acknowledges reception of a SHUTDOWN chunk
• ERROR chunk — reports various error conditions
• COOKIE ECHO chunk — used during the association establishment process
• COOKIE ACK chunk — acknowledges reception of a COOKIE ECHO chunk
• SHUTDOWN COMPLETE chunk — completes a graceful association close