VoIP Help Center

Session Initiation Protocol - SIP

Executive Summary

All Voip explains sip clients, the sip protocol, sip proxy, sip servers, sip softphones, sip telephones, and sip voip

Voice over IP, commonly know as an Internet phone, is becoming very popular both as free service and paid services. Are you in business? Do you want to profit from SIP voice? Are you just looking for telephones and a no-cost service provider? Establishing a WiFi network or Internet access for your school, town, or city? Network integration issues?

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Don't be confused by terms such as VOIP and SIP. VOIP stands for Voice over IP, but now many companies want to call it "voice over Internet phone", which sounds easier but technically is not right. IP stands for Internet Protocol. SIP stands for session initiation protocol. Simply put, if you get a free Internet phone you will be using VOIP because you are talking over the Internet. SIP is the connection that connects you to other phones. Most of this is behind the scenes and requires no intervention on your part. SIP proxies are simple devices. Once a call is connected the end devices can exchange data directly. The proxys do not have to be on the path and they are only involved in the setting (and later the ending) of the session.