[lwip-users] Receive window in active open

[Biren Patel]

Hi,

While opening an active connection, lwIP sends SYN to peer with window size
equal to TCP_WND. When lwIP receives SYN-ACK from peer, it copies the value
of window that peer sent in SYN-ACK as it's own receive window(tcp_input.c:
line 455) and from there on uses that as a receive window. As a result of
this, both sides use the same receive window. This doesn't happen during
passive open from lwIP side.

Is there any special reason behind forcing lwIP to set it's receive windows
as equal to peer's receive window?

As far as I know, both sides of the connection are allowed to use different
receive window and it's illegal for lwIP to change it's receive window.

Regards,
Biren.