Choosing layer 2 encapsulation protocols

[polm]

I'm not sure how to explain why a particular layer 1 setup would allow for, or require, a particular lyaer 2 encapsulation.

When it comes to Cicuit Switched vs. Packet Switched vs. Leased Line.

Particularly in ISDN, which is Circuit Switched, can I use HDLC or cHDLC ?

 

[spidey07]

you generally use PPP on ISDN.

 

[polm]

Originally posted by: spidey07
you generally use PPP on ISDN.

but could you use HDLC ? If not, why ?