Extra latency at ATT exchange for UVerse

William Pitcock nenolod at systeminplace.net
Thu Nov 11 20:22:14 CST 2010

On Thu, 2010-11-11 at 15:39 -0500, Srikanth Sundaresan wrote:
> Can anyone explain why ATT's UVerse adds significant delay to packets
> compared to their ADSL service?

U-Verse is actually the name of two entirely different services - VDSL
and FTTP.  This is a typical symptom of stupidity on behalf of marketing

The VDSL service uses interleaving, but since they use actual fibre in
my neighbourhood (I have an ONT on the side of my house and everything)
I can't really tell you what impact the interleaving has.

Friends of mine on VDSL say it's about an additional 20ms penalty or so.
Perhaps it's the interleaving?

If you log into your RG, it will tell you if you are on VDSL or are
connected to an ONT.  I think what your case is, is that you are on VDSL
and very close to an IX as far as AT&T's network is concerned.


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