VoIP电力通信系统中防火墙及穿透技术

介绍了基于VoIP的多媒体通信系统.由于电力通信网络的特殊性,要求对承载的业务要有更高的可靠性,对不同区域之间的通信要有足够的安全保护.文中分析了系统的安全问题以及如何穿透防火墙,该多媒体通信系统之所以不能顺利穿过防火墙,是因为系统采用的协议将目的端IP地址嵌入到第5层,而防火墙只能看到第3层.根据这一特点,提出了增加代理、引入可以分析高层协议的应用层网关及建立隧道3种解决方案.

SECURITY TECHNOLOGY IN VOIP BASED ELECTRIC POWER COMMUNICATION SYSTEM

A voice over IP (VoIP)-based multimedia communication system is described. Owing to the particularity of the power electric communication network, an even higher reliability of the operated business and sufficient security protection are required of the communication between different regions. The security problem and the problem of how to penetrate the firewall are analyzed. The reason that multimedia communication system can not penetrate through firewall is that the protocol system used embeds the IP address into layer 5, but the firewall can only get IP address of layer 3. According to this characteristic, three solutions are recommended as adding proxy, introducing ALG (apply layer gateway) that can analyze protocol of higher layer and setting up tunnel between two networks.This work is supported by the Youth Research Fund of State Power of China (No. SPQKJ02-04) and Nanjing Automation Research Institute (No. NARI-2002-06).