RST
FIN

connect()
	ack=seq
	seq=Ǥ > 0
	SYN|ACK
accept()
	ack=seq
	seq=ack
	ACK
send()
	ack<=seq
	seq=ack
	ACK
recv()
	ack=seq
	seq>=ack
	ACK


small ack
equal
large seq