On Monday, December 20, 2010 06:36:03 pm you wrote:
> Those are all still sub-T1 on the uplink and well below normal CMTS service
> speeds. Low-end CMTS is around 15Mbps/7Mbps.

Yeah, at least with the T-1 you aren't oversubscribed.  One company for whom I 
consult was going to go from their T-1 to an 11/1 DSL, but they do streaming 
audio and video, and I was able to talk them out of it.  I've been asking the 
provider to sell that place a matched pair; give me an 11/1 DSL, and then give 
me a 1/11 reverse ADSL on a different pair, and I'd be a happy camper.

> The AT&T cable plant in my neighborhood is unable to
> sustain any better than 1.5mbps/384k on ADSL.
 
> > Their copper in my area is nearly new, they have spent the last five years 
> > or so refreshing and updating their copper outside plant.  
 
> That helps a lot. It still doesn't compete with CMTS which was my point.

Interestingly enough, we've tried to do H.323 with some folks on a CMTS 
connection, and have yet to succeed in smooth video.  My testing on my home 
DSL, back when it was 1.5M/.5M (we got two free upgrades; the first one was to 
5/.5 and the second to 7/.5) and our main link was an OC3 to a different 
provider, went well.  Never really figured out what it was causing the problems 
with the CMTS users; the effect was that the H.323 session would start up and 
negotiate at 384Kb/s, and a few seconds of video would traverse fine, and then 
the link would start dropping more and more frames until it died entirely; my 
testing on my slower DSL didn't have this problem, and traceroute showed an 
equivalent number of hops between.  The CMTS connection in use was an 8M down 
1M up link.

And I don't have cable available to me at all.  So it's DSL or nothing at home; 
even Verizon's 3G, which works fairly well at work, doesn't work at all at 
home, 1,200 feet away (terrain issues).  And I don't have visibility to the 
most common data satellites on the Clarke Belt. 

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