Incoming call from unknown IP address or 4 digit number(eg:1000) in Cisco Video conferece sys

[blesso-victor]

Hi Team,

Please help us out to avoid unwanted call(which may be from IP address or any 4-digit number) which we are receiving frequently from Cisco Video conference system. Currently we have 4 VC unit in our organization which all are configured with the common IP address to make and allow client to join with us.

So please let us know solution to fix this issue permanently.

Thanks and Regards,
Blesso

[Jens Didriksen]

This is a known issue which has been extensively dealt with in this forum on a large number of occasions, take a look at https://supportforums.cisco.com/discussion/12917996/sip-spam-call-attack-and-mcu-and-vcs-e and you'll find links there to a number of other threads dealing with this issue.

/jens

Please rate replies and mark question(s) as "answered" if applicable.

[Patrick Sparkman]

Are these endpoints configured with a public IP address, if so you need to put them behind you're firewall to prevent the incoming calls you don't want, then restrict access through the firewall to only allow calls from known external endpoints. If you have a VCS, then you should disable SIP UDP if it is enabled. 

As Jens suggested, take a look at the various links he's provided, as they contain information as to why you're getting these unwanted calls and how to best mitigate them.