My doubt

Question

In connection termination of tcp....suppose client got the fin segment from server and and it send acknowledgment to server..and goes to time wait state...now suppose this acknowledgment is lost.....and server retransmit the fin segment to client which is in time wait state...now after receiving fin segment again client transmit ack again .....but suppose again that acknowledgment is lost......so my question is what will happen to client and server ....when they will go to closed state???

Please anyone explain....

Comments

according to what i know, after the server has sent the FIN, it starts a TIMER and releases the connection after TIMER expires. similarly, client also starts a TIMER after sending the ACK and it too releases the connection after the timer expires.

theoritically, there is no full-proof way to release the connection in sure-shot way that both sides received the required segments of fin and ack. if anyone tries to make a protocol, say 4-way handshake or 5- way, so on, none will suffice the problem. the way you are trying to release the connection can go on forever.

practically, 3-way handshake is there to release the connection will 2 timers, one at client side and one at receiver side after sending their last segments(which is FIN for server and ACK for client)

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