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Community Member

VOIP with Cisco uBR900 Cable Modem Router

Quick question. I am new to VOIP. I just setup my modem/router and I've noticed it has VOIP capabilities. Now, when I plug my phone into the VOIP port. I get a ring tone. But when I dial a number, right away I get a busy signal. I am guessing that since I get a ring tone from my phone that my ISP is configured for VOIP. Am I right? Or is this telling me that my ISP does not have me configured for VOIP or they don't support it at all?

Cisco Employee

Re: VOIP with Cisco uBR900 Cable Modem Router

Your 2nd guess is correct. Voice over IP on cable modems will only work properly in a Cable network if the service provider has set up their system to support it. Here is the url explaining that

It has really good faq's for cable modems.

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