Good article must read it.
http://newsweaver.co.uk/accastudent/e_article000502554.cfm?x=b3SQ42M,b2yWP3w5,w
If you have extra info then add it here.
Thank You.

Good Nice Short Article.

Kazza has worst repute for infringing copyrights of music but in this article its sister product is referenced skype.Would it not been better to reference Google Talk ?

But Kazza has never lost any legal case. 8)

More information about how voice over internet protocol ( ip telephony ) can be read here http://computer.howstuffworks.com/ip-telephony.htm

A good detailed website about voip http://www.voip-info.org/wiki/

What is vonage?

Vonage is company using VOIP like Skype uses.