In This Topic
^ Deciding on your signaling choice
^ Looking into the SIP methods
^ Understanding the responses to methods
VoIP isn’t a protocol, it’s more of a concept. A community of programmers wanted to send voice calls over the Internet, and they made it happen. With VoIP, one piece of software doesn’t do all the work. A team of individual software elements, doing specific jobs, works together to make it all happen. They’re all vital participants, and losing any one element of the team stops VoIP from working.
This topic familiarizes you with the signaling software element of VoIP, which functions like a project manager. The protocol described in this topic doesn’t do any of the heavy lifting in VoIP transmissions; it identifies the VoIP hardware responsible for the call and the basic rules of engagement between them. It doesn’t break the voice portion of the call into packets or handle the transmission of the packets. It just makes sure that both ends of the call are in communication. Several VoIP protocols exist, and each choice affects the hardware you need, the networks to which you can connect, and possibly how you need to design the voice portion of your LAN.
