A Session Border Controller (SBC) is a critical network device that protects and manages real-time communication sessions such as VoIP calls, video conferencing, and SIP trunking. Positioned at the edge of an IP network, it ensures secure and seamless communication between internal systems and external networks. An SBC helps prevent cyber threats, manages call traffic, supports interoperability between different vendors, and maintains high voice quality. For businesses using IP PBX or unified communications, a Session Border Controller plays a key role in delivering reliable, secure, and optimized communication performance.