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Capture output explanation
Hello, I am facing a problem between 2 machines and i installed Wireshark version 3.2.0 to capture the network traffic. While i am able to ping the target machine from the source machine, when i am trying to connect to port 22 i cannot connect. I started a capture while trying to connect to target machine using both telnet and winscp application. It is a short capture but i do not know what is the problem. These are some of the data that i receive in the capture:
Internet Protocol Version 4, Src: source, Dst: target
Transmission Control Protocol, Src Port: 51877, Dst Port: 22, Seq: 0, Len: 0
Source Port: 51877
Destination Port: 22
[Stream index: 1]
[TCP Segment Len: 0]
Sequence number: 0 (relative sequence number)
Sequence number (raw): 2742951259
[Next sequence number: 1 (relative sequence number)]
Acknowledgment number: 0
Acknowledgment number (raw): 0
1000 .... = Header Length: 32 bytes (8)
Flags: 0x0c2 (SYN, ECN, CWR)
000. .... .... = Reserved: Not set
...0 .... .... = Nonce: Not set
.... 1... .... = Congestion Window Reduced (CWR): Set
.... .1.. .... = ECN-Echo: Set
.... ..0. .... = Urgent: Not set
.... ...0 .... = Acknowledgment: Not set
.... .... 0... = Push: Not set
.... .... .0.. = Reset: Not set
.... .... ..1. = Syn: Set
.... .... ...0 = Fin: Not set
[TCP Flags: ····CE····S·]
Window size value: 65535
[Calculated window size: 65535]
Checksum: 0x8352 [unverified]
[Checksum Status: Unverified]
Urgent pointer: 0
Options: (12 bytes), Maximum segment size, No-Operation (NOP), Window scale, No-Operation (NOP), No-Operation (NOP), SACK permitted
[SEQ/ACK analysis]
[TCP Analysis Flags]
[Expert Info (Note/Sequence): This frame is a (suspected) retransmission]
[The RTO for this segment was: 3.000277000 seconds]
[RTO based on delta from frame: 4]
[Timestamps]
Please advise.