But what exactly is the difference between IP PBX and SIP? If you're considering upgrading your communication system, understanding these differences is crucial. Let’s break it down. IP PBX (Internet Protocol Private Branch Exchange) is a phone system that manages internal and external calls using VoIP technology. SIP is a signaling protocol used to initiate, maintain, and terminate real-time communication sessions, such as voice calls, video calls, and messaging over the internet. Whether you’re looking for better internal communication or seamless remote work capabilities, understanding these technologies will help you make an informed decision.