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For a standard telephone to plug into broadband simply requires a phone adapter (from, say, Linksys or Cisco) to bridge between the two. This electronics could easily be incorporated into a Vodafone router. Does Vodafone intend to supply this modified router together with a SIP account to support it, or will they be handing their landline telephone business over to someone else, like Sipgate, for example?
For a standard telephone to plug into broadband simply requires a phone adapter (from, say, Linksys or Cisco) to bridge between the two. This electronics could easily be incorporated into a Vodafone router.
The current router, THG3000, already has the VOIP hardware incorporated.
There is no electronics in the adapter used with the THG3000, it's just wires to match the connectors.
Unfortunately Vodafone will not supply the details to allow you to use it with your own VOIP supplier.
So, what you are saying is that, when I can no longer plug my phone into the wall socket containing the splitter because the old service has been withdrawn, I will be able to plug the same phone into my THG3000 using one of the telephone sockets, just using a dumb adaptor so the phone plug fits. So the forward path to continue using the Vodafone landline is already installed, ready to use! Wonderful!
Assuming you are moving to a FTTP service, that is correct.
Apparently the installer is expected to supply the adapter, but rarely does.
If you need one this is recommended. rhinocables® RJ11 Plug to BT Socket with tail Telephone Adaptor White : Amazon.co.uk: Electronics & ...