RE: Dialup congestion and winter weather (fwd)

[Roeland Meyer <rmeyer () mhsc com>]

1) I'm my own ISP, dialing into my own modem banks. I am reasonably
confident that I know what my own systems are doing. They are not
interacting as you describe.

2) Local loop-back tests show that my servers see full bandwidth, on their
last mile. Similar testing on the NC "last mile" show the bandwidth
contraints.  Since the bandwidth is constrained on the "last mile", the LD
trunk behavior is irrelevent. Although, that was a probability, until I did
the tests.

3) You really wouldn't believe the telco attachment equipment I carry in the
*other* half of my lap-top case. On the road, I can attach to the
tin-cans-n-string communications network, if I have to. Even if it does add
15 pounds to the carry weight<g>.

-----Original Message-----
From: Christopher Grupe [mailto:cgrupe () nortelnetworks com]
Sent: Wednesday, January 03, 2001 7:56 AM
To: Roeland Meyer; 'multics () ruserved com'; nanog () merit edu
Subject: RE: Dialup congestion and winter weather (fwd)


He Sent, 
> -----Original Message----- 
> From: Roeland Meyer [mailto:rmeyer () mhsc com] 
> Sent: Wednesday, January 03, 2001 12:53 AM 
> To: 'multics () ruserved com'; nanog () merit edu 
> Subject: RE: Dialup congestion and winter weather (fwd) 
>
>
>
> That isn't the only issue. I've just found that Southern Bell does
bandwidth 
> limiting on their residential customers. Most folks would never know the 
> difference, but when v.90 modems start consistantly connecting at 14.4K, or

> less, then I know that the telco is only allowing 32K per voice channel 
> (rather than the usual 64K). BTW, that was using AT&T universal LD from 
> Graham, NC, to Livermore, CA. I only ever got full-speed late at night. 


Come on, 
The ISP is not going to write an init script for their modems to permanently
have them connect at 14.4. Telco's don't turn down the PCM rate on dial up's
to 32KBps either... Telco's (RBOC's) have a separate (unregulated) ISP,
which handles dial up traffic. The regulated side is the switched side
(voice switch).... One has nothing to do with the other (usually union
workers on the regulated side, and non-union on the unregulated side). So to
prove your point, the dial side (ISP non-union) would call the CO's and have
the Switchman changed the line card to an ADPCM (32Kbps) card at the switch,
and the ISP sets their modems to connect at 14.4Kbps. No way Jose!

Some CLEC's are running their line cards using ADPCM (32Kbps) and over an
ATM backbone. The RBOC's at this time are still using typical PCM (64Kbps)
per channel, for the line cards (unless using BRI).
The problem you may be experiencing is with the inter switched trunks, or
coming in a span that has timing slips, Errored Seconds, and severely
errored seconds, etc. Especially if you are going LD from NC to CA.
Christopher Grupe 
Sr. Sales Engineer 
Nortel Networks, Service Provider & Carrier 
cgrupe () nortelnetworks com 
I speak for myself!