Posted - Jun 18 2001 : 6:59:49 PM
Well, I am not 100% sure of my answer. It seems that the D channel is using LAPD for encapsulation and the B channels must rely on other encapsulation protocols, such as PPP (which is using a flavor of HDLC as encapsulation). I’ve found this explanation in a book, but I’m not quite confortable with this answer.
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