Hello,
I have a TWG870 from Thomson, and i don't have access to the SIP configuration through the admin page. The SIP config page seems to be hidden.
I've found a pdf document (http://www.broadbandnetworks.ch/files/pdfs/BNET-White%20Paper-TWG870,%20...)
who explains that there's some MIB available for this modem, but, impossible for me to find them through SNMP.
If you see page 4 of the doc, WebUiControlConfigFileTlvMaker is a tool to generate the String for the Access Mask, but it's the same, impossible to find it.
If you have some informations about this cable modem, you're welcome
Thanks
Julien
Did you enabled voip advanced setup page or maybe you have a working config file for this modem ?