[En-Nut-Discussion] Opened TCP connection. Watchdog timers going ok here. Realtek stopping for a breather.

[Harald Kipp]

Not sure wether I fully understood the problem.

But in general it's like Robert said. TCP is designed
to keep socket connections open for years without
transmitting anything.

That's one reason why the receiver would never
detect, that the sender is already gone. It hangs
there endless (unless you use timeouts).

I never observed any long time instabilities of the
Realtek/SMSC either.

May be any of your other application parts (OK, even
a Nut/OS part) contains a memory whole and make TCP fail
as soon as something is coming in? Did you check this
using NutHeapAvailable()?

Harald