On Fri, Nov 6, 2020 at 1:03 AM David Laight <david.lai...@aculab.com> wrote: > > Hmmm.... LAPB would expect to have an X.25 level 3 and maybe ISO > transport (class 0, 2 or 3) sat on top of it.
I actually used AF_PACKET sockets to transport data directly over LAPB and it worked. LAPB doesn't need anything from layer 3. It just sees the layer 3 packets as a sequence of packets, numbers them and reliably transports them in order. It doesn't read the internal contents of the packets.
