VoIP #

VoIP vs SIP #

In simple terms, VoIP means making or receiving phone calls over the internet or internal networks. SIP, on the other hand, is an application layer protocol that is used to establish, modify and terminate multimedia sessions such as VoIP calls.

A major difference between VoIP and SIP is their scope. VoIP is not a discrete technology in its own right. Rather, it is actually a family of technologies used within modern telecommunication networks, whereas SIP is a signalling protocol used within the VoIP umbrella.

A further difference is that, whilst VoIP sends only voice messages, SIP can carry all forms of media, not just voice messages. Transmitted via data networks, SIP trunks send packets, which may include voice, data, or video content. This means that SIP systems allow users to make voice and video calls online, often for free.

参考：

• Key differences between SIP & VOIP