Anti virus wall is a kind of network security equipment which is located at the entrance of the network (Gateway) and is used to filter the virus in the network transmission. The anti-virus wall can be deployed at the junction of the enterprise LAN and the Internet to prevent viruses from invading the intranet from the Internet.
人类步入了二十一世纪，信息产业飞速发展，互联网正在迅速地发展和普及。伴随而来的是计算机病毒的日益猖狂。尽管许多企业已经具有了一定的安全防范意识，并且部署了网络版杀毒软件和硬件防火墙，但是在面对诸如 SQLSlammer 等新的蠕虫病毒时，仍然显得力不从心。面对现今恶劣的互联网安全状况，只有强有力的防毒墙才能保障企业网络的安全。
With the rapid development of information industry and the rapid development of Internet, human beings have entered the 21st century. Accompanied by the computer virus is increasingly rampant. Although many enterprises have a certain sense of security, and deployed the network version of anti-virus software and hardware firewall, but in the face of new worms such as SQL rammer, it is still unable to cope. In the face of today’s harsh Internet security situation, only a strong anti-virus wall can guarantee the security of enterprise network.
Anti virus wall is a kind of network security equipment which is located at the entrance of the network (Gateway) and is used to filter the virus in the network transmission. Generally speaking, the anti-virus wall can be deployed at the junction of the enterprise LAN and the Internet to prevent viruses from invading the intranet from the Internet. All viruses have certain characteristics. The anti-virus wall will scan the packets passing through the gateway, then scan the data for viruses, and clear them if they are viruses. In theory, the anti-virus wall can prevent any virus from entering the internal network of the enterprise from the gateway.
根据国际著名病毒研究机构 ICSA（国际计算机安全联盟，International Computer Security Association）的统计，通过磁盘传播的病毒仅占 7%，剩下 93%的病毒来自网络，其中包括 Email、网页、QQ 和 MSN 等传播渠道。
According to the statistics of ICSA (International Computer Security Association), only 7% of viruses are transmitted through disks, and the remaining 93% come from the network, including email, web page, QQ and MSN.
The technical analysis report on China’s computer virus epidemic situation investigation released by the public information and Network Security Supervision Bureau of the Ministry of public security shows that the proportion of computers spreading through CD-ROM, disk and other storage media has decreased significantly, while the number of virus infected through network downloading and browsing has increased the most. E-mail has also increased. The trend of computer virus networking is more and more obvious. How to effectively defend against network virus is an important task in the future.
Domestic anti poison wall
The vast majority of enterprises in China are using the network version of anti-virus software + firewall to protect the normal operation of the enterprise network.
A set of antivirus software is deployed in the enterprise network. It can check and kill the virus inside the enterprise and ensure the security of the enterprise network system to a certain extent, but it still has great limitations.
First of all, the network version of anti-virus software installed on the original operating system, so the stability of the operating system itself and whether there are loopholes have a certain impact on the use of network version of anti-virus software. Second, although the network version of anti-virus software can check and kill viruses, it can not guarantee that viruses enter the LAN from the Internet.
Moreover, more and more network viruses begin to attack and spread by exploiting the vulnerability of operating system. From the vulnerability patch released by the operating system manufacturer to the emergence of the virus spreading through this vulnerability, the time for the system administrator to repair the system is also shorter and shorter. But if the operating system is not repaired in time, these viruses can easily bypass the anti-virus software and directly infect the computer, which greatly reduces the effectiveness of anti-virus software. How to prevent the virus from entering the internal network has become the primary problem faced by various enterprises.
Many enterprises have gradually realized that it is not enough to use network version antivirus software for protection. More and more enterprises have begun to use hardware level protection products to cooperate with it, such as network firewall, intrusion detection system and so on. However, for viruses, can these protection products really effectively intercept network viruses?
Limitations of firewall
1. Unable to guard against internal user attacks
2. There is no way to prevent connections that do not pass through it
3. Limited useful network access
4. It’s hard to guard against viruses
5. Unable to guard against new network security issues
6. Data driven attacks cannot be prevented