here i have number of FDR produce data and transmitted to local server through internet when i capture traffic strange retransmission packets appear repeatedly why ?? please find attached http://www.mediafire.com/download/bnw155591jf5fj5/tcp_stram_0.pcapng how come the data source send retransmit request thank you asked 24 May '14, 09:53  shady |
One Answer:
A retransmit is not a request - keep in mind that everything in square brackets are things that Wireshark adds, not something that is part of a packet. Looks like you have retransmissions because the ACK did not get back to the sender, e.g. frame 30 is retransmitted in frame 34 even though it was ACKed in 32. answered 24 May '14, 11:11  Jasper ♦♦ |
thank you for your reply
in the file you downloaded i separated only one TCP stream
in the complete capture file you will find the same problem for all TCP conversation
another point all retransmissions are always sent from the sender (FDR)this indicate a problem in server configuration
or what is the cause of this problem ?
packet loss is rarely a server configuration problem. Usually packets get lost on the network due to congestion or other problems.
Congestion means that when a link is overbooked packets will be buffered at first, but if more and more are coming in they will be discarded. Which results in retransmits.