[lwip-users] STM32F4+lwIP: TCP MSS sets to 536 bytes on its own

[Jagdish]

Hi,
Am using lwIP stack with STM32F4 series micro-controller in one of project
board. Trying to connect this board to pc based application. I observed,
When host sends packet of size 1088 bytes, the packet gets divided into 2.
Please refer the packet where length column shows 590 and 552. 
In lwiopts.h, i have set TCP_MSS to 1460. Also the initial TCP handshake
shows the MSS is 1460 from both PC and stm32f4 board. 
My understanding is that if in initial handshake the MSS is 1460. Host must
not divide the packet in 2 segments restricting the length of packet to 536
bytes.
Kindly help me to understand and set this right. Is there a configuration in
lwIP or on PC side that i am missing?

<http://lwip.100.n7.nabble.com/file/t2089/TCP_MSS_Image.png> 

Thanks.
Jagdish



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