A SIP proxy server is a network component that acts as an intermediary between two or more Session Initiation Protocol (SIP) clients, facilitating the establishment, maintenance, and termination of SIP sessions. It provides routing, call forwarding, and other services to support SIP-based communications.
SIP proxies are crucial for managing SIP traffic in complex network environments, improving call quality, and enhancing security. They enable flexible call routing, allowing organizations to distribute incoming calls across multiple devices or locations based on pre-defined rules. Additionally, SIP proxies provide features such as presence information, call recording, and conferencing, extending the capabilities of basic SIP clients.