TCP Header Starting Source port Destination port sequence Sequence number number(byte ofset) of data Acknowledgment carried in this HdrLenlo flags Advertised window packet Checksum Urgent pointer Byte streams numbered Options(variable) independently in Data each direction 45TCP Header Starting sequence number (byte offset) of data carried in this packet Byte streams numbered independently in each direction 45 Source port Destination port Sequence number Acknowledgment HdrLen 0 Flags Advertised window Checksum Urgent pointer Options (variable) Data