To filter traffic has these advantages:

It can help reduce security risks and prevent inappropriate usage.

It can provide greater control over the traffic that passes through the security appliance.

Note: Because URL filtering is CPU-intensive, the use of an external filtering server ensures that the throughput of other traffic is not affected. However, based on the speed of your network and the capacity of your URL filtering server, the time required for the initial connection can be noticeably slower when traffic is filtered with an external filtering server.

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