呼叫中心会话边界控制的一种设计与实现

A Design and Implementation of Session Border Controller in Call Center

本课题以北京欣方新通信呼叫中心为依托,针对公网坐席的注册和通话功能的需求,提出了一种基于SBC(会话边界控制)的SIP协议NAT穿越方案。当位于公网上的SIP终端向SBC发起注册和会话消息后,SBC作为一个背靠背用户代理,更改SIP消息中的联系地址,向内网软交换转发注册和会话请求,将外网与内网的软交换连通,使得外部网络的终端用户可使用公司内网的ACD模块进行注册、通话,扩展呼叫中心的业务。文中详细分析了不同应用场景下的NAT穿越流程,并设计测试用例对此方案的可行性进行了测试,成功完成了在不更改任何网络配置和网络设备的前提下透明的NAT穿越。

This topic relies on the Call Center of CINcc. According to the registering and calling requirements of agents in the public network, this paper proposed a SBC （Session Border Controller） based solution to SIP traversal NAT. When the agents send the register and invite messages, SBC, as a B2BUA, changes the contact address in SIP messages and sends the messages to the soft switch in private network. SBC connects the soft switches in public and private networks and makes it true that the agents in the public network can also use the ACD module in private network to register and make calls. It expands the business of call center. The results of functional analysis under different applications and performance test showed that the proposed NAT traversal is available to implement transparent traversal with no change required for network configuration.