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PBX dedicated switches use specialized technology and lack openness and standardization. In recent years, with the popularity of the Internet and the success of IP, IP PBX based on IP protocol has emerged, which is expected to solve the shortcomings of traditional PBX. The control center within the IP PBX local area network can effectively manage the computer network and telephone network according to the specific situation inside and outside the office, achieving resource sharing. Through the Internet, IP PBX networks in different regions can achieve long-distance communication, electronic office, and e-commerce.