Which TCP control flag is used to initiate connection establishment?
The SYN flag initiates TCP connection establishment. Since SYN is not listed among options A-C, the correct choice is None of the above.
Which TCP control flag is used to gracefully close or terminate an established connection?
The FIN (Finish) flag is transmitted when a sender has completed data transmission and requests graceful termination of its half of the connection.
Which TCP control flag causes an immediate, ungraceful abort or reset of an invalid connection?
The RST (Reset) flag immediately aborts a connection upon detecting invalid packets, closed ports, or severe out-of-sync protocol errors.
In TCP, what mechanism is employed to provide end-to-end flow control to prevent sender from overwhelming the receiver's buffer?
TCP implements flow control using an advertised receiver window (rwnd) field in the TCP header, allowing dynamic sliding window buffering.
What happens when a receiver advertises a TCP Window Size of 0 (Zero Window)?
When rwnd = 0, the receiver's buffer is full. The sender stops transmitting application data and periodically sends 1-byte Window Probes using a persist timer to check for buffer reopening.