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Re: (ASCEND) T1 provisoning hints
It looks like we're on track with the trunk side T1 but I've still got the
connect problems. If they can connect at 56flex speeds from California
doesn't this lead you to believe that it's coming in to our box too hot
locally. The boxes are only 30' from the switch, which may not make have
any impact on this. Like I said before, he put a 1 db on the line to trunk
when it makes the conversion. This should be zero I assume. What do you
think I should try? Should I change this to nilpadgrp and then try
adjusting LBO in the max? I could really use a lesson on how the db level
would be affected by a call from California or locally. The way that it's
been explained to me is that from my house to the C.O. the best I can
expect is a 3 db drop, then it hits an EAS trunk which usually has another
3db, at the switch we are putting in the 1db for a total of -7db when it
hits the Max, and data should be about -13db. From California they would
come it at -3 at the best, drop 6 in the toll trunk, and another 1 at the
office for a minimum of -10. If they had more loss on their end from the
C.O. this could drop it close enough to the -13 we're looking for. Is this
the way the padding works on the D/A conversions. I can understand the db
drop in the copper easy enough but I'm having trouble comprehending how
they pad it before it goes to the toll, EAS, and t1 trunks.
Thanks again,
Greg
----------
> From: Dave Van Allen <dave@fast.net>
> To: 'Greg Hale' <greghale@logantele.com>; 'ascend-users@max.bungi.com'
> Subject: RE: (ASCEND) T1 provisoning hints
> Date: Saturday, June 28, 1997 1:08 AM
>
> Hi Greg, thanks for the nice words.
>
> Let me try to illustrate line-side versus trunk-side in the context of
> what we're talking about here.
>
> As you know most switches, and certainly your DMS-10, can have (at
> least) 2 different ways to connect to subscriber equipment. When
> someone says that you are connected to the line-side of the switch, they
> mean that you are connecting to individual, separate, analog ports that
> have exactly one CO line. For all intents and purposes, the line-side
> delivers classic electrical Tip and Ring, and you hook that up right to
> copper paths.
>
> RBOC's, when they buy switches have to satisfy the bazillion pairs of
> copper that ingress to the CO, and they do that by buying line-side
> packs for the switch.
>
> Trunk-side is classically the digital side, and I believe got it's name
> from that fact that "trunks of lines" were delivered in a digital format
> from those packs. So the trunk-side of the switch would normally
> aggregate 24 individual phone lines onto a T1 for delivery to customer
> PBX's and such that know how to decode that format properly. This side
> of the switch is truly digital, and has no analog component associated
> with it. This is the "side" of the switch that you *want* your T1's
> delivered from, and it is the "side" of the switch that all PRI are
> delivered from.
>
> Here's the rub: Joe's ISP Inc. calls the RBOC, Bell Atlantic for
> instance, and orders up a "channelized T1" from the Telco. They tell
> Joe that this will be delivered on a T1 digitally to Joe's location. It
> will have 24 voice channels, and they will all hunt to each other. It
> will have a format and framing of B8ZS, ESF. Joe checks the Ascend Web
> page, and all looks good so far.
>
> Then, and very often, and without your knowledge the RBOC will take 24
> line-side CO lines (remember, they're analog at this point!) and run
> them into a D4 (or some other) channel bank that takes the 24 analog
> lines, and multiplexes them onto a digital T1 to send to you. The
> problem is that they added an A/D conversion in the path that you are
> unaware of. This kills the whole party. You *must* be very specific
> and ask for engineering verification from the RBOC, that there is
> absolutely no A/D in the T1 path at all. (BTW, this is a classic reason
> for never seeing 28.8K connections, but seeing loads of 26.4's)
>
> I used Bell Atlantic as an example because of my experience with them.
> FYI, Bell Atlantic *always* provisions line-side T1's. They do not have
> a tariff for trunk side. If you want trunk-side from BA, you first must
> be enlightened enough to ask, then they must issue for internal approval
> what is known as an HSA, or House Special Assembly. BA's charges for
> trunk-side HSA T1's is close to $80 buck a line, with a $2000 install.
> All RBOC's have the equivalent of an HSA - it's their way of getting
> around tariff's for special circumstances.
>
> Nynex, on the other hand has a product they call FlexPath, which IS
> provisioned trunk-side.
>
> Clear as mud? :-)
>
> Best regards,
>
> David Van Allen - You Tools Corporation / FASTNET(tm)
> dave@fast.net (610) 289-1100 http://www.fast.net
> FASTNET - PA/NJ/DE Internet Solutions
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