If you want VoIP but do not want to acquire hardware or be responsible for installing Asterisk, this post is for your consideration.
In the https://www.myciscocommunity.com/docs/DOC-15495 document, I describe how you can sign up for a free Asterisk server, no strings attached.
I've recently acquired a free hosted Asterisk PBX server from Aretta Communications and have successfully registered my SPA525G IP phones within minutes.
Enjoy,
Patrick
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