n. 防火墙（firewall 的复数）
1.Web servers can be protected by the use of "firewalls".
服务器或网络有问题。稍候再试。
2.Web servers can be protected by the use of "firewalls".
服务器或网络有问题。稍候再试。
3.Web servers can be protected by the use of "firewalls".
多播也能减少网络服务器上的负荷。
4.They could be the firewalls of any building.
它们可能是任何一座楼房的隔火墙。
5.As hackers turned up, layers of security, from antivirus programs to firewalls, were added to try to keep them at bay.
随着黑客的出现，从防病毒程序到防火墙的层层安全措施被添加进来，试图阻止他们。