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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Using snort to detect if your users are doing interesting things?
Drew Weaver wrote: > Howdy, I am not sure if this is the proper place, if not > I've noticed you guys know what to do so I'll put the fire retardant > suit on now. Recently due to growth we have seen an influx of > "different" and "interesting" types of characters ending up on our > network. They like to do all sorts of things, port scan /8s spam, setup > botnets with the controllers hosted on my network.. etc. I'm wondering There are two basic methods, I guess: 1. You search for specific patterns. For example for somebody pinging more than n addresses in a specific time frame. If you know what you are looking for, you can set something up to do it easily. 2. You look for something strange. You will need some kind of statistical method then. They have a tendency to produce false positives from time to time, so you better look at the results closely. > I did have one somewhat silly question.. if you look at the statistics > of a Fast Ethernet port, and it is doing both 2000 pps out, and 2000 pps > in (pretty much equal in/out) but hardly any bandwidth at all can anyone > think of a single application that would mimic that behavior? DNS-Servers? Nils begin:vcard fn:Nils Ketelsen n:Ketelsen;Nils org:Kuehne + Nagel (AG&Co) KG;Ham MI-GP adr:;;Ferdinandstr. 29;Hamburg;;20095;Germany email;internet:[email protected] tel;work:+49 40 32915 236 tel;fax:+49 40 32915 500 tel;cell:+49 172 4451246 x-mozilla-html:FALSE url:http://www.kuehne-nagel.com/ version:2.1 end:vcard
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