> 	PMTUD is designed with assumption that link MTUs are stable (do not
> 	change over time).

So the simple approach (limiting to something a bit higher and leaving 
figuring the optimal value to the admin) is the way to go?

Would 1500-sizeof(struct mobile_h) be a reasonable upper limit for the MTU or
should we make that basically unlimited (i.e. 0xffff), relying on the admin
to know what he is doing?

Martin