Encounter some problem with my Server. To understand this require good knowledge in TCP/IP Segment and 3-way handshakes
Here is the sequence of 3-way handshakes:
1) Host B --> Host A, src port:1878 dst port: 2000
[SYN] Seq=0 Ack=0 Win=16384 Len=0 MSS=1460
2) Host A --> Host B, src port: 2000, dst port: 1878
[SYN, ACK] Seq=0 Ack=1 Win=8192 Len=0 MSS=536
3) Host B --> Host A,
[TCP ZeroWindow] src port:1878 dst port:2000 [RST]
Seq=1 Ack=1576600895 Win=0 Len=0
1) Host B has not problem connecting to Host A all the while.
2) When Host C starts to download file from Host A, Host B gets connection
3) In packets debugging, it shows Host B send RST packets to Host A to
terminate the connection.
4) The TCP 3-way handshakes are not able to establish at all. SYN-ACK can
not be acknowledged by Host B.