batteryworm's profile - activity

Thanks for asking. No, the issue is still unresolved. Both sender and receiver are running Linux. Sender side is by defa

Thanks for your comment. Really appreciate it. We have asked sysadmin from receiver side about their implementation of T

A couple of other things to take note. Sender side tcpdump is taken at server OS level hence you see large MTU sizes,

I am still trying to get the 3-way TCP handshake which happens hours before the segment of the capture that points to th

SACK is not enabled. https://www.dropbox.com/sh/akzfjk2nb7on9oc/AADePEu_WhCSnPqahPUDov3Ba?dl=0 I have removed data field

Thanks for your comments. We have been trying to get the pcap from the other side but no response so far. Will update if

Receiver sends window update instead of DUP ACK I have an issue whereby sender sends a bursty chunk of data across a WAN

Reason behind TCP RST from Client I need someone to help me interpret what is going on with the tcpdump I have - this is

Reason behind TCP RST from Client I need someone to help me interpret what is going on with the tcpdump I have - this is

Reason behind TCP RST from Client I need someone to help me interpret what is going on with the tcpdump I have - this is

I have an application that uses API to connect to server separated by a WAN. The problem is that it can establish a 3 way TCP handshake, but after that could not connect at the API level and after some time (20 seconds), the session disconnects. A tcpdump is taken at the client end who initiates the connection; at the same time a tcpdump is taken at the server end.

1. At the client end, we can see client sending SYN, then receiving SYN-ACK from the server, and client sends ACK. Subsequent to this TCP session establishment, client then sends data (32 bytes) with PUSH, ACK. But there is no response from server. After 300 ms, client retransmit the data packet (same packet with 32 bytes) ie. retransmit. Again no response from server. After 600ms, client retransmit same data packet. No response from server. After 1.2 seconds, client retransmit; no response from server. This goes on for another few times, after about 11 seconds, client sends a RST to server; no response from server. Again client sends RST to server and no response. This repeats several time. Until finally at about 20 seconds, client receives RST from server.
2. At the server end, we can see the SYN packet from client. Server response with SYN-ACK. Then server receives ACK from client so the TCP 3 way handshake is established. Subsequent to this server does not receive any more packets from client. After 20 seconds, server sends RST to client. What causes this behaviour?

Thanks for your suggestions. A call to Company B network and server admin resolved the issue. It was due to a wrong rout

Just to add. I took a closer look at company B pcap. Noticed at the MAC layer the server seems to be communicating to tw

To clarify, this is not a HTTP protocol. It is a proprietary protocol using port 23027. I will attempt to describe the i

To clarify, this is not a HTTP protocol. It is a proprietary protocol using port 23027. I will attempt to describe the i

Why no data flow after TCP 3 way handshake? I have an application that uses API to connect to server separated by a WAN.