Tearing Down Connection Either side can initiate tear down A B Send FIN signal FIN SegA Im not going to send any more data CK, SegA+1 Other side can continue Data sending data ACK Half open connection Must continue to acknowledge FIN, SeqB Acknowledging FIN ACK, SeqB+1 Acknowledge last sequence number 1 Lecture 18: TCP Details8 Lecture 18: TCP Details Tearing Down Connection • Either side can initiate tear down • Send FIN signal • “I’m not going to send any more data” • Other side can continue sending data • Half open connection • Must continue to acknowledge • Acknowledging FIN • Acknowledge last sequence number + 1 A B FIN, SeqA ACK, SeqA+1 ACK Data ACK, SeqB+1 FIN, SeqB