Charles N Wyble <[email protected]> wrote:

> Well there are a couple decent sized CLECS still around. DSLExtreme is a
> CLEC.

It depends on how you define a CLEC.  I don't know (or care really) how
the telco lawyers define it, but to me a true CLEC is someone who has
put up their own physical gear in a CO cage or in the outside plant.

DSLExtreme is not that: they don't have their own DSLAMs anywhere, they
just have an interconnection agreement with ATT (and probably VZ too)
that gives them access to ILEC's regular ADSL DSLAMs at the ATM PVC
level.  I call this a front-end.

> Speakeasy is a CLEC (though I think they got bought by BestBuy as
> I recall. Kind of a weird purchase.).

Speakeasy was also a front-end like DSLExtreme, not a DSLAM back-end
operator, and they are now part of MegaPath too.

> Well SDSL/T1 are viable options.

Aha, it's interesting to hear this from someone other than me.  Would
you care to elaborate?  Just when would you consider SDSL/T1 to be a
good choice?  Even more specifically, when would you consider SDSL/T1 to
be a better choice than ADSL/U-Verse/FiOS/cable?  Up until now everyone's
been saying in one voice that the latter are superior by every metric.

> SDSL being more so due to the lower cost,

Heh.  Covad/MP salesmen would much rather sell you T1 than SDSL, but
that's because they are most likely commission-based.  Just ignore them
and insist on SDSL if you want something that's just like a T1, but a
little cheaper.

If one does an apples-to-apples comparison between 1.5 Mbps SDSL and a
T1, the main disadvantage of SDSL is that thanks to the dismantling of
all Copper Mountain DSLAM networks, you get ATM cells on your line.  My
OSDCU or the Paradyne iMarc box will convert this SDSL/ATM to HDLC on
your side, but you still have to live with less efficient use of that
1.5 Mbps bit pipe.  OTOH, if you get a T1, they do the ATM to HDLC
conversion in the DSLAM for you, so the 1.5 Mbps bit pipe carries the
more bit-efficient HDLC.

> and the substantial effort put into your SDSL CPE.

Heh.  All I've really done is created a new device that does SDSL to
V.35.  (Here I use V.35 in a generalized sense that includes EIA-530 as
well.)  As I have learned much later, SDSL-to-V.35 CPE devices for all
flavors including Covad's did exist prior to my project, and I've even
obtained samples of each.

But here's the thing: V.35 is so obscure and there are so few people who
want it, that it actually took me /less/ time to design and build my own
(including reverse engineering of the SDSL signal format) than to obtain
one of the pre-existing devices that does the job, or even find out
about their existence!

Time line:

2004/2005: got SDSL from Rhythms/MCI (CM flavor), wanted a Larscom
CupreDSU box to convert it to V.35, couldn't get one.  Started looking
into building my own, but got sidetracked.

Early 2006: got moved to Covad SDSL when MCI became VZB, but didn't
really understand the difference then.  Kept looking for a CupreDSU
thinking that it would help me, but still couldn't find one.

Mid 2006: cracked an encrypted ZIP with SDSL transceiver firmware source
code, started on the project in earnest.  Learned the difference between
Rhythms/CM/HDLC and Covad/Nokia/ATM flavors.

Oct/Nov 2009: built my own OSDCU board that recreates the functionality
of the CupreDSU, and also supports ATM-to-HDLC conversion for Covad.

Dec 2009: finally laid my hands on a stash of CupreDSU units I had been
looking for for 5 years.  It took me a little less time to design and
build my own from-scratch replacement in the meantime!

Jan 2010: learned about the existence of the Paradyne iMarc unit (and
obtained a couple of them) that converts SDSL/ATM to V.35/HDLC just like
my OSDCU.  (Same functionality that is, the actual implementation is
very different.)

Feb 2010 through present: finishing up my OSDCU just so that I don't
leave the project unfinished, even though there should be enough XSB-2000
and Paradyne iMarc units in the stashes of Covad-MP to satisfy all 50
other Michael-Sokolov's out there who want V.35 instead of Ethernet.

My passion is about V.35.  If someone wants to get SDSL service with
V.35 hand-off instead of Ethernet (or convert an existing SDSL service
from Ethernet to V.35 hand-off), I will be equally eager to support you
whether you prefer my OSDCU or one of the existing historical ultra-
obscure SDSL to V.35 devices.

> > Option 2: MP can sell you SDSL, 2x bonded SDSL (they call it 3 Mbps
> > Ethernet, damn marketing),
>
> Hmmmm. That's interesting. Calling it ethernet is misleading. Unless
> they are providing l2 access, site to site connectivity etc (ie metro
> ethernet offerings).

They call it "Ethernet" because "Ethernet" sells better than "SDSL".
They provide an MLPPP router (sourced from my competitor Adtran) and
just tell their users: "plug into this Ethernet jack right here and
don't worry about anything else", that's how they call it "Ethernet".

If someone wanted to get this bonded SDSL service *without* the Adtran
box, it would require escalation and getting me in on a 3-way call with
your MegaPath account rep.  Or just put the Adtran box in the driveway
and drive over it with a truck, then get an open source replacement from
Harhan.

For extra credit, make a home video of the Adtran box being run over by
your truck, upload it to YouTube *over the connection served by the
Harhan replacement*, and send a link to your MP account rep.  Can also
Cc a few executives whose E-mail addresses I can provide.

> Wait.... what does Covad/MP own? They don't just lease
> infrastructure/space/copper plant (unbundled network elements) from the
> ILEC?

They own the Nokia D50 MCS and LCS chassis and the cards in them (just
like the one in my lab), but they do indeed rent the CO space where
those chassis reside, and all facilities that interconnect them.

> Got it. Something like
> http://www.business.att.com/content/product/images/dsl_Copy.gif

That picture is quite accurate indeed.  But for maximum accuracy, in
the yellow-colored CLEC part replace "DSLAM" with "LCS", and replace
"ATM Switch" with "MCS".  The Nokia D50 DSLAM is actually a distributed
two-stage architecture, and I suspect that Covad has put only the LCS
part of it in every CO.  One MCS can manage up to 12 LCS boxes, and I
wouldn't be surprised if Covad manages with a single MCS per 12 CO
sites.

MS
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