Sequence Numbers Host a ISN (initial sequence number) equence TCP TCP Data ACK sequence number from a number from B 1st byte of =nex↑ data expected byte TCP CP Data LHDR Host b 48Sequence Numbers Host B TCP Data Host A ISN (initial sequence number) TCP Data TCP HDR TCP HDR Sequence number from A = 1 st byte of data ACK sequence number from B = next expected byte 48