Need help understanding TCP sequence number and ACK number -

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how sequence number generated? let's sender sends 2 packets:

seq number: 68 ack number: 69 length: 62 bytes
seq number: 130 ack number: 131 length: 62 bytes

and recieves packet reciever sequence number 131 og ack number 130, sequence number next time sender sends packet? 131+62=193?

"when host initiates tcp session, initial sequence number random; may value between 0 , 4,294,967,295, inclusive. "

at sender: - send 1 packet, , keep track of sequence number ,   transmission time - once ack received packet, delete stored   sequence number, , send new packet (using same strategy   of saving sequence number , waiting ack) - if ack hasn't been received after timeout seconds since   packet's transmission time, retransmit receiver.   @ receiver: - upon receipt of packet k, send ack packet k - if k greater last sequence number received (or if   haven't received packets yet), deliver packet   application , keep track of k  example : host a: seq#: 111 ack #: 0 host b: seq#: 222 ack #: 112 host a: seq : 112 ack#: 223

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