Cisco Expressway-E search rules and call policy best practices

[marco_81]

Hi all,

i open this discussion to ask some questions about protecting Exp-E from undesired inbound calls.

I have Cisco Exp-E configured with search rules to route incoming calls from Internet to reach the internal dial-plan only, search rules are configured to route calls only toward trusted destination, that is on-net dial plan.

No Call Policy are in place.

With search rules and no call policies in place, an external malicious attempt to reach some international number (for example) is correctly not routed internally, with 404 Not Found sent to the external malicious caller.

Deploying Call Policy to block this kind of attempts would send 403 Forbidden to the malicious caller instead, and no search rule would be computed.

My question is: Is it a best practice to deploy Call Policy for this kind of scenario, even if the search rule alone would not route malicious calls?

thanks for help!

[Anurag Srivastava]

Hello,

I think making call policy will be better because if you are doing it through search rule for every call your Exp-E need to process and check for a matching rule which is an unnecessary task for it and suppose if these calls comes in high number then?

Also you can refer the below link for more discussions-

https://community.cisco.com/t5/telepresence-and-video/sip-spam-call-attack-and-mcu-and-vcs-e/td-p/2868418

Thanks

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