Industry Forums > Wireless Service Providers > DSL Deployment - How hard w\Verizon as the ILEC?

reply to iansltx

Re: DSL Deployment - How hard w\Verizon as the ILEC?

ADSL2+ Annex A

ADSL2+ Annex M

Annex M Profile - Annex A was the same.

Interesting. However what's the big deal with a single db of attenuation over the lack thereof, when the connection provides 1 Mbps more on the upload side?

Thanks for doing the test. 35/4 at 11kfeet (bonded ADSL2+ Annex M) seems like an attractive proposition when the competition doesn't go above 2 Mbps up and 15 Mbps down...

Acutally it's 4db attentuation on the upstream, I was looking at the SNR margin when I wrote that - Looking at one thing and writing another, sorry.

Just like wireless you have to be careful of your SNR margins, too little margin and the modem re-syncs and become unstable. We use 6db SNR as the target, however we will begin to see issues at 4db or less. Generally I have my DSLAM's setup to begin fall back at 3db to slower speeds to increase the SNR. That 1db of SNR margin can easly be a go-nogo point.

Sure. The drastically decreased upstream SNR is interesting, however for businesses that are close-in bonded ADSL2+ Annex M seems promising.