In our organization, we keep receiving random calls from: 60200, 501
When we answer the call, the call drops.
It looks like SIP Vicious call or ghost call.
We have cisco ASA Firewall
I have very new in Cisco Firewall.
The VLAN for VOIP is 650.
Can someone guide or advise me, what shall i check in our Cisco Firewall step by step.
I do have access to Cisco Firewall through Cisco ASDM.
