Cisco SPA 112 Phone Adapter & ISP

[recent2Cisco]

I'm replacing my relative's ISP provided all-in-one cable modem/wireless router/VoIP with their own cable modem and firewall/router (separate devices).  I've purchased a Cisco SPA 112 phone adapter so they can keep their VoIP as well.  The ISP is telling me that I can't use a 3rd party phone adapter.  Does this sound correct?

[Dan Lukes]

It may or may not be true.

SPA112 speak SIP on provider's side, it support a set of audio codec ...

... if your voice service provider (not the ISP ! unless it's the same) doesn't speak SIP (or speak SIP with some proprietary extensions only) or use a codec unsupported by SPA112.

We know nothing about undisclosed voice provider in question (and it's requirements) so no way to provide more specific answer to you.

[recent2Cisco]

The ISP is Time Warner/Spectrum.  I'm not sure what their requirements are unfortunately.  Thank you for the reply.

[Howard Wittenberg]

I believe Time Warner/Spectrum is a Cable "TV + Internet + Voice" provider. Companies of that type typically offer a telephone service package combined with their other services over their network and require their own interface hardware. They usually have technicians to perform the installation.

As an alternative, you could obtain voip service from an independent voip provider such as CallCentric, Voip.ms, Callwithus, etc, and use your SPA112 adapter which you would ethernet cable attach to a router connected to your Time Warner Internet service.

[recent2Cisco]

Yes, Time Warner/Spectrum is the provider of my relative's Cable/Internet/VoIP and a technician did perform the installation.  Interestingly though, they are using an Arris Surfboard cable modem TG1672G.  That doesn't seem to be their own equipment though.  Anyone can purchase those.

I did explain to them they could use an independent VoIP provider, however, they didn't want to pay the extra price for one when the phone was a part of their current cable service. 

Thanks for the reply.

[Dan Lukes]

TG1672G uses MGCP (TGCP?) over PacketCable to carry phone calls. It's dissimilar to SIP.

[recent2Cisco]

Ahh, thanks for the info.  I appreciate your reply. 

Seeing that leaves out using the SPA 112, has anyone ever setup a secure open source VoIP solution and put it in a DMZ, or port forward, so I can use the SPA 112?  Maybe use Asterisk?

[Dan Lukes]

Seeing that leaves out using the SPA 112, has anyone ever setup a secure open source VoIP solution and put it in a DMZ, or port forward, so I can use the SPA 112?  Maybe use Asterisk?

---

I'm unsure I understand your question. You claimed:

didn't want to pay the extra price for one when the phone was a part of their current cable service

Did you changed the mind ?

mentioned you wish to use

[recent2Cisco]

It was just a question.

[Dan Lukes]

OK. With a SIP VoIP provider outside, it should be possible to use SPA112 directly - or you can setup Asterisk inside and connect SPA112 to it.