I have a BT Home hub on BT Inifinty Fibre service and BT Talk VOIP service. What I want to do is change my BT Home Hub for a Draytek wifi router.
Firstly will the Vigor 2850 Series VDSL/ADSL Router cover my needs and has anyone the config setup for the BT voip service to enable me to setup a Draytek.

Regards
Roger

This should help:
The details need to be obtained from BT directly or by doing the following:

Visit the www.bt.com/bbv page, enter your account details and on the next page click the "Configure Hub/Router" link which will load a page with a red "Configure" button on it.
Right click that button and select "Open in a new window", the SIP account information sent to the Hub will be displayed in the web address bar (where you normally type in www.), highlight and copy the string into an application such as Notepad.
It will show as a single block of text so it will help to put a new line before each & sign for clarity.

It will look like this:

http://www.api.home/voipsetup.api?SIPTransportProtocol=UDP
&SIPTransportPort=5060
&SIPRegistrarAddress=sip.bbvservice.nat.bt.com
&SIPRegistrarPort=5060
&SIPOutboundProxyAddress=www.bbvservice-560049x.bt.com
&SIPOutboundProxyPort=5060
&SIPProxyAddress=sip.bbvservice.nat.bt.com
&SIPProxyPort=5060
&SIPPhoneNumber1=05600******
&SIPCallerName1=
&SIPUsername1=05600******
&SIPPassword1=ABCDEFGH12IJK3L
&SIPPhoneNumber2=
&SIPCallerName2=
&SIPUsername2=
&SIPPassword2=
&SIPHashB=d171f7f6123fbce2e80446dc1b06a8fa
&SIPHashC=3f8b49b05078a0c0a5cd3d5c82c33f7a
&SIPHashD=777a74c8a8bb129636e6c3cbfae8a811
&SIPHash=4c8d061c965d073308634b261532a180

- SIPRegistrarAddress corresponds to the Domain/Realm setting
- SIPRegistrarPort corresponds the to SIP port (normally 5060)
- SIPOutboundProxyAddress corresponds to the Proxy setting
- "Act as outbound proxy" must be ticked
- SIPPhoneNumber1 corresponds to the Account Number/Name and Authentication ID
- "Authentication ID" must be ticked
- SIPPassword1 corresponds to the Password setting

And yep, the 2850Vn can have a BT talk SIP account registered with it and connect to ADSL / VDSL (which is BT fibre)

thanks for the BT work around. the guy on the VoIP help desk said he was giving me all the info I needed but witheld the domain/realm details. I found them using your advice and it is now working! thanks thanks thanks!