Huawei eSpace U1981 Unified Gateway (hereinafter referred to as U1981) is the core of the voice gateway Huawei unified communications solutions, supporting Huawei's IP terminal and unified communications applications, to provide professional voice over IP solutions and unified communications solutions. U1981 pure SIP architecture, highly integrated, single-box support 10,000 users; broadband and narrowband integrated design, supports analog and IP telephones hybrid network; by digital trunks, analog trunks and SIP trunk implementation and operation of broadband connected device's network or private network voice switching. Huawei eSpace U1981 Unified Gateway highly integrated, feature-rich IP-rich voice service capabilities built-fidelity voice conferencing to support a variety of conference mode support One Number service, any time, any place important calls, built-in voice mail service, do not miss any Caller high stability, high reliability of 99.999% carrier-class reliability redundant backup of key modules effective control and cost savings number analysis and black and white lists, precise control of call range 32 custom permissions, enterprise multi-level password control call restriction, effective control of call Cost Intelligent routing, reduce communication costs for rapid deployment, easy maintenance and visualization tools, installation is simple and fast unified network management, improve maintenance efficiency built-in Web management interface, easy operation