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trAnsport protoCols
When a TCP-BUS sender receives the ERSN message, it under-
stands, for the sequence number of the last successfully received pack-
ets at the destination and the sequence number of packets at the head
of the queue at PN, that the packets will be delayed further and hence
uses a selective acknowledgment strategy instead of fast retransmis-
sion. e last packets are retransmitted by the TCP-BUS sender.
During the retransmission of this last packet, the network congestion
between the TCP-BUS sender and PN is handled in a way similar to
that in traditional TCP.
Advantages include:
• Improved performance
• Uses of buffering, sequence ...