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Why mss not the same?

So I was having an issue with packet loss accessing an app via telnet. So, I captured from the host (site A) and from the firewall close to the server (site B). The firewall can run tcpdump.

On the host, the 3-way HS the SYN from the host has the mss set to 1460 and the SYN,ACK from the server the mss is set to 1398.

On the firewall (close to the server), the SYN from the host has the mss set to 1400 and the SYN,ACK from the server the mss is set to 1460.

Both of these captures were taking in different locations, but at the same time. Shouldn't the 3-way HS show the same results on both ends if both were used to capture the same telnet session?

Why mss not the same?

So I was having an issue with packet loss accessing an app via telnet. So, I captured from the host (site A) and from the firewall close to the server (site B). The firewall can run tcpdump.

On the host, the 3-way HS the SYN from the host has the mss set to 1460 and the SYN,ACK from the server the mss is set to 1398.

On the firewall (close to the server), the SYN from the host has the mss set to 1400 and the SYN,ACK from the server the mss is set to 1460.

Both of these captures were taking in different locations, but at the same time. Shouldn't the 3-way HS show the same results on both ends if both were used to capture the same telnet session?

Why mss not the same?

So I was having an issue with packet loss accessing an app via telnet. So, I captured from the host (site A) and from the firewall close to the server (site B). The firewall can run tcpdump.

On the host, the 3-way HS the SYN from the host has the mss set to 1460 and the SYN,ACK from the server the mss is set to 1398.

On the firewall (close to the server), the SYN from the host has the mss set to 1400 and the SYN,ACK from the server the mss is set to 1460.

Both of these captures were taking in different locations, but at the same time. Shouldn't the 3-way HS show the same results on both ends if both were used to capture the same telnet session?

Why mss not the same?

So I was having an issue with packet loss accessing an app via telnet. So, I captured from the host (site A) and from the firewall close to the server (site B). The firewall can run tcpdump.

On the host, the 3-way HS the SYN from the host has the mss set to 1460 and the SYN,ACK from the server the mss is set to 1398.

On the firewall (close to the server), the SYN from the host has the mss set to 1400 and the SYN,ACK from the server the mss is set to 1460.

Both of these captures were taking in different locations, but at the same time. Shouldn't the 3-way HS show the same results on both ends if both were used to capture the same telnet session?

Why mss not the same?

So I was having an issue with packet loss accessing an app via telnet. So, I captured from the host (site A) and from the firewall close to the server (site B). The firewall can run tcpdump.

On the host, the 3-way HS the SYN from the host has the mss set to 1460 and the SYN,ACK from the server the mss is set to 1398.

On the firewall (close to the server), the SYN from the host has the mss set to 1400 and the SYN,ACK from the server the mss is set to 1460.

Both of these captures were taking in different locations, but at the same time. Shouldn't the 3-way HS show the same results on both ends if both were used to capture the same telnet session?