TCP Header Source port Destination port Acknowledgmen Sequence number t gives seq just Acknowledgment beyond highest HdrLenlo flags Advertised window seg receIvea In order Checksum Urgent pointer If sender sends Options(variable) N bytestream bytes starting at Data seq s then “ack” for it wi‖l be S+N 47TCP Header Acknowledgmen t gives seq # just beyond highest seq. received in order. If sender sends N bytestream bytes starting at seq S then “ a c k ” for it will be S+N. 47 Source port Destination port Sequence number Acknowledgment HdrLen 0 Flags Advertised window Checksum Urgent pointer Options (variable) Data