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在诸如 Intemet、企业内部网络(Intranet)以及新兴服务提供商的外部网(Extranet)之类的传统数据网络上传输电话服务,如今已经成为可能,并且发展迅猛。这一技术的发展,直接导致了基于内嵌式系统的高效网关设备的发展,这些设备能够将语音、传真等模拟电话信号转换成数据包,以便在 IP、帧中继以及ATM 网络上传输。于是,很久以前要通过替换或是改进 PBX 交换机以便将语音和数据服务合并到同一个网络的许诺终于变成了现实。为了实现这一功能,要求价格低廉的电话交换设备能够直接和数据网络交换数据包。IP 电话的发展要求芯片系统也同步发展,能够集成数字信号处理(DSP)功能、微控制(MCU)功能、模拟接口、电话用户接口、网络接口以及相关的逻辑
Telephony services are now being deployed on traditional data networks such as the Internet, intranets, and emerging service providers’ extranets, which are now possible and rapidly evolving. The development of this technology has led directly to the development of highly efficient gateway devices based on embedded systems that convert analog telephone signals such as voice and fax into packets for transmission over IP, Frame Relay and ATM networks. As a result, the promise of replacing the PBX switch with a long time ago to consolidate voice and data services onto the same network has finally come to fruition. In order to realize this kind of function, require the low-cost telephone exchange equipment to exchange the data packet directly with the data network. The development of IP telephones requires the simultaneous development of chip systems that integrate digital signal processing (DSP) functions, micro-control (MCU) functions, analog interfaces, telephony interfaces, network interfaces, and related logic