HDLC protocol and NRM and ABM

[zillah]

NRM= Normal Response Mode

In this scenario we have one primary station and multiple secondary startions. A primary station can send commands; a secondary station can only respond.

The NRM is used for both point-to-point and multiple-point links.

ABM: Asynchronous Balanced Mode

In this scenarion, the link is point-to-point, and each station can function as a primary and a secondary.

What is it meant by sending command and responding ?

I think it has been meant by point-to-point, for the link, not for point-to-point protocol,,,,,Has not it?

[darkfiber1010]

Yeah I’m fairly certain it means a point to point link. What curriculum was that from Cisco?

[zillah]

What curriculum was that from Cisco

It is not from Cisco, it is from the book "Data Communications and Networking" 3d by Forouzan chapter 11 section 11.5 HDLC

http://highered.mcgraw-hill.com/sites/0072.../student_view0/

[darkfiber1010]

Oh ok, looks like a good book. After awhile they all start sounding the same