On occasion, I get as many as 50-60 bogus calls that look like this:
2011-12-01 17:03:20,SIP/76.74.253.98-0000035f,unknown,""“unknown”" “,600,ANSWERED,6
2011-12-01 17:03:28,SIP/76.74.253.98-0000037b,unknown,”"“unknown”" “,200,BUSY,1
2011-12-01 17:03:30,SIP/76.74.253.98-00000383,unknown,”"“unknown”" “,200,BUSY,1
2011-12-01 17:03:32,SIP/76.74.253.98-0000038b,unknown,”"“unknown”" “,200,BUSY,1
2011-12-01 17:03:34,SIP/76.74.253.98-00000393,unknown,”"“unknown”" “,200,BUSY,1
2011-12-01 17:03:36,SIP/76.74.253.98-0000039b,unknown,”"“unknown”" “,200,BUSY,1
2011-12-01 17:03:38,SIP/76.74.253.98-000003a3,unknown,”"“unknown”" ",200,BUSY,1
I think this is because my SIP trunker (Callcentric) requires “Allow Anonymous Inbound SIP Calls” setting.
I realize someone may be looking for a vulnerability. Nothing has happened, but it is a bit of an annoyance.
Can anything be done to prevent these?