Ascend Archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
(ASCEND) Channelized T1 - 56k and debugging
Howdy folks,
We have several MAX 40xx's, each running either 5.0p5 or 5.0p6
on Channelized T1's
with AMI/D4 on some T1's, and B8Zs/ESF on
others. These are trunk side T1's, no
D/A conversions along the path. We're thoroughly testing our connection
rates, and
haven't seen rates higher than 34k with supraexpress modems, and 38k with
motorola modemsurfer modems. Dialing long distance with AT&T to various
test
numbers, we've seen rates usually at 46k or 42k with the supra express.
Ascend
claims to get 46k dialing long distance to our ascend, but we have not been
able to
repeat that test ourselves. We've talked with our carrier, and it appears
there should
be no difference in the way a long distance call to us is routed, and a
local call.
Our receive levels are fine, and we know of no D-A conversions on our T's.
Just the
fact of getting 34k about 15% of the time with the surpa express indicates
that 56k
is negotiable- but I really have no idea what it means when only low kflex
speeds
are negotiated. I've read the white papers, and my theory is that there
may be some
kind of line impairment- but I can't prove it. There have been some
reports on this
list of the MAX units being more finicky with channelized T1's. A local
ISP with
PRI has 56k working just fine, and we're stuck at very poor performance.
What I'm looking for is:
1- Has anyone with channelized T1 gotten 56k to work on a MAX? On a PM3?
2- How can I tell if there is a problem with the channelized T1's? Are
there any
magic debugger commands to help diagnose problems?
I've also been dialing into the thing thousands of times, recording receive
levels and
such- and my local modem (consumer 56k modem) reports a receive level of
about
-25 to -27dB on a non-KFlex speed connection to our 56k max, and it's -15dB
on
a KFlex speed connection. I don't exactly trust the supraexpress numbers
though.
(I'm getting this information by using at&v1 and at%q1 about 1 second after
the modem
reports a CONNECT.) I also am curious about the "RBS counter" number the
modem
reports. I'm guessing that RBS stands for Robbed Bit Signalling.
If anyone has any ideas on how to troubleshoot this, please let me know.
We're
looking at USR and Livingston equipment now. I expect similar results, but
since
there seem to be few channelized T1 MAX users out there, there could be
some
serious flaw in the CSU of the MAX for dealing with channelized T1 -- and
it would
make sense that KFlex would make any bugs more apparent.
Thanks everyone, and especially Ascend- I really like the MAXes, and their
kflex
performance is just horrible for us.
-Will
--
Will Pierce
System Administrator
Dreamscape Online, LLC.
willp@dreamscape.com
++ Ascend Users Mailing List ++
To unsubscribe: send unsubscribe to ascend-users-request@bungi.com
To get FAQ'd: <http://www.shore.net/~dreaming/ascend-faq>
or <ftp://ftp.shore.net/members/dreaming/ascend-faq.txt>
Follow-Ups: