I'm currently receiving over 200 SIP REGISTER requests per second from a machine apparently in Italy, host97-239-149-62.serverdedicati.aruba.it. This has continued for several days, and ab...@staff.aruba.it are unresponsive. I've had a couple of similar incidents recently, the others originating from uk2.net.
I have an ADSL connection and responding to these REGISTERS was consuming all my outbound bandwidth. I am now dropping the packets but still some 600kbps of inbound bandwidth is consumed by this. The packets look something like this: REGISTER sip:62.3.200.113 SIP/2.0 Via: SIP/2.0/UDP 62.149.239.97:5086;branch=z9hG4bK-2570753370;rport Content-Length: 0 From: "test" <sip:t...@62.3.200.113> Accept: application/sdp User-Agent: friendly-scanner To: "test" <sip:t...@62.3.200.113> Contact: sip:1...@1.1.1.1 CSeq: 1 REGISTER Call-ID: 3778139552 Max-Forwards: 70 I'm guessing the 'friendly-scanner' bit is sarcastic, as there is little that is friendly about this behaviour. Has anyone else experienced this? Is this intended as a DOS attack, or is it a dictionary attack? Or something else? What is the best strategy for dealing with it? For now I have started rate limiting SIP connections to Asterisk, but what is a reasonable rate for each host to be allowed? This is a small SOHO installation. Thanks Chris -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users