Router - ZyXEL P660HW-T1
This page is regarding a legacy product.
The ZyXEL P660HW-T1 v2 routers sometimes do not do ADSL2+ full speeds and Annex M in their default configurations.
Here is how to modify the router's configuration in order to get the best speed out of your BT or TT ADSL2+ line:
ADSL2+
Sometimes the router reports ADSL2 DELT mode, and has low sync rates (~7 meg) on a line that can support more. The ADSL2 DELT is a red herring. This is a 7.1 meg max sync.
Telnet in, then type: "sys edit autoexec.net" Press "i" You should see a colon When you see the colon, type the following command: "w dmt2 set largeD=2" Press enter, then press "x".
You can verify that autoexec.net contains the new command by typing "sys view autoexec.net".
After a reboot, the sync rate should be increased. This only applies to the T1v2.
Annex M
The router does not do Annex M by default; it needs forcing.
Telnet in, then type:
"sys edit autoexec.net"
Press "i" You should see a colon When you see the colon, type the following command:
"wan ghs set annex m"
Press enter, then press "x".
You can verify that autoexec.net contains the new command by typing "sys view autoexec.net".
After a reboot, the upstream sync rate should be increased, at the expense of some downstream.