MSS Value

[jonk34567]

Hi,

I capture a tcp handshake in wireshark. In it the TCP MSS value is 1452 bytes but the maximum tcp segment value does not exceed 1440 bytes througout the connection. What is the reason ??

[balaji.bandi]

The calculation done based on certain parameters - I would suggest a very nice document here to understand :

https://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/25885-pmtud-ipfrag.html

[Reza Sharifi]

Hi,

In the handshake process, you should see TCP MSS value 1460 which is 1500-40=1460

HTH