>This is because most vendors still believes that T1 circuits are provision
>as D4/AMI..Digital Link Encore csu/dsu by default has it setup as
>ESF/B8ZS.I'm evaluating the new cisco 2524 with internal CSU/DSU, and it looks
like the default is ESF/B8ZS on this box too. Maybe there's hope for
the vendors catching up with reality on this front afterall.
I haven't touched a 2524 yet. Is the DSU options set on the command line?
Anyone have experience mixing different vendor CSU/DSUs and getting
things like remote loopback to work?
In-band and out-of-band lookpback codes should work fine. The differences
I've seen are with in-band codes. Some CSUs need to see the loop-up
code unframed, and some will respond to the loop-up code framed.
Rememeber that you can't send an out-of-band loop-up code unless
(a) you're ESF framed, and (b) the CSU is optioned to acknowledge
any o-o-b request.
An Out-Of-Band code is also known as an ESF code. The loop-up or loop-
down requests are sent in the 4kbps ESF channel instead of the actual data
channel/path.
Also remember that CSU and NIU (Network Interface Units) codes are
different. Make sure you're sending a CSU code. An NIU code is
technically called a Facility-2 code (FAC-2).
Since one mfgr's unit can't be configured to send a framed or unframed
loop-up/down (it doesn't tell you), you're at their mercy. Same if you
want to send an in-band or out-of-band code.
With a test set, though, I've never run across a CSU or NIU that I couldn't
loop up or down. You can virtually set a test set to do _anything_.
rob.
p.s...I have the data sheet scanned in. I'm gonna html it.