lots of qs

[Chetan Sakhardande]

1) what is the difference between an asynchronous link and a bit oriented
sunchronous link? What do PPP, SLIP support ?

2) why is trailr encapsulation (in thernet) no longer used ?

3) where is the kernel stack for a procerss in linux ?

4) what is the use of the mapped_from_device fd flag?