防火墙是位于计算机和它所连接的网络之间的软件。计算机流入流出的所有网络通信均要经过防火墙。今天的防火墙被用来保护计算机网络免受非授权人员的骚扰与黑客的入侵。这些防火墙尤如一道护栏隔在被保护的内部网与不安全的非信任网络之间，我们目前广泛使用的互联网络便是世界上最大的不安全网，近年来媒体报导的很多黑客入侵事件都是通过互联网络进行攻击的。防火墙可以使你的网络规划清晰明了，有效防止跨越权限的数据访问。使用防火墙是保障网络安全的第一步，选择一款合适的防火墙，是保护信息安全不可或缺的一道屏障。
參考答案:The firewall is located between network software which the computer
and it connects. The computer flows in all networks correspondence
which flows out to have to pass through the firewall. Today firewall
is used for to protect the computer network to exempt is must been
authorized personnel's harassment and hacker's invasion. These
firewall especially like together guard rails separate in internal net
which protects with the unsafe non- trust network between, we at
present the widespread use internet then is in the world the biggest
not safety net, in recent years the media reported very many hackers
invade the event all are carry on the attack through the internet.
The firewall was allowed clearly to cause your network planning to be
bright, effectively prevented surmounted the jurisdiction the data
accessing. Uses the firewall is safeguards the network security the
first step, chooses a section appropriate firewall, protects the
information security indispensable together barrier.
