What is a SIP server?

A SIP server is the main component of an IP PBX, dealing with the setup of all SIP calls in the network. A SIP server is also referred to as a SIP Proxy or a Registrar.

An example of a SIP server is 3CX Phone System - a Windows-based SIP server

IP PBX, SIP & VOIP common questions 

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• What are the benefits of an IP PBX?
• IP PBX: How an IP PBX / VOIP phone system works
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• What do the terms FXS and FXO mean?
• What is a STUN Server?
• What is a good source of VOIP info?
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• What does ENUM mean?
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