Generally speaking, firewalls have the following functions:
1. Allow network administrators to define a central point to prevent illegal users from entering the internal network
.firewall router。
2. You can easily monitor the security of the network and alarm.
3. It can be used as a place to deploy NAT (Network Address Translation), using NAT technology to dynamically or statically associate a limited IP address with an internal IP address to alleviate the problem of address space shortage.
4. It is the best place to audit and record Internet usage fees. The network administrator can provide the management department with the cost of Internet connection, find out the location of the potential bandwidth bottleneck, and can provide department-level billing according to the accounting model of the organization.
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