ADSL2 vs ADSL1 line compatibility

[mwedel]

A few days ago, but ADSL2 modem (ZTE provided by Sonic) bit the dust.

For short term, I'm using an ADSL 1 modem I got at a thrift store until I can get a proper replacement. I talked to sonic tech support, and the Sonic provided modem is out of warranty, and given I just need a basic modem, I think it is a better deal for me to buy a replacement than pay the $6.50 lease charge.

Before the ADSL 1 modem could sync, the tech person had to change the line setting for me (I think multimode was mentioned).

My question is that after I install a new adsl 2+ modem, is there any need to have the line switched back to how it was before if everything works fine? I'm not exactly sure when it got switched in the past - I know shortly after going to fusion, I had packet drop issues which was fixed by sonic tech changing some setting, and I've also used Annex M once when doing a large upload.

[kavan]

You may want us to bump the speed cap up a little once you have the new modem in place. It looks like ADSL2+ will run a bit faster than where your cap is currently set. Multimode (which you are currently set to) will sync in the best available protocol being 1, 2, or 2+. Annex-M does need to be set independently though.

[mwedel]

Got the new modem installed and gave support a call. The person I talked to said that based on line stats, going any higher would likely result in dropped packets or reliability issue.

But in poking within more menus of the DSL modem, I ran across the stats page, portion of it:

SNR Margin (dB): 6.1 16.1
Attenuation (dB): 36.0 21.3
Output Power (dBm): 13.0 0.0
Attainable Rate (Kbps): 12388 1280
Rate (Kbps): 9247 984

I have no idea if the SNR and attenuation numbers presented there are good or bad. I do see that what the modem claims is attainable is much higher than I have right now, so I don't know if that is overly optimistic.

I do remember when I first had fusion installed, the rate cap was put in place because I was getting some packet loss - not a really high percentage, but anything much above 0% makes playing online games pretty painful.