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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: NSPs and filters
On Sat, 12 Jul 1997, Jon Lewis wrote: > On Sat, 12 Jul 1997, Phil Howard wrote: > > > It isn't, or shouldn't be, an issue of whether the customer wants this > > kind of service. This is protection FROM that customer. The principle > > reason to not do this is the load it causes on the router. > > > > Should it be discovered that source forged packets are coming from a given > > customer, then you could apply this to that customer if they are not going > > to just be summarily cut off. > > The trouble is, unless you are silly enough to attack your own provider, > it seems unlikely that they will know you are spoofing. i.e. In my > current situation, I doubt UUNet's ability or willingness to track these > packets to their source. Hi, On Friday our network was suffering an identical attack as yours. We are a UU-NET customer. Once I had traced the exact neture of the attack, port numbers etc, I contacted UU-NET who *did* trace the source of the attack to one of their customers - I think inside AS701. I was pretty impressesed - took them about an hour - I didn't overly think that they would find the source but they located it down - with some help from the source customer to the individual machine. I doubt it is the same person doing the attacks as the source port for us was 13 (?) and the size of udp packet was 1000 - but both attacks probably from the same program. Is there any way to put the originating AS into the (options part?) header of all ip packets as they leave one's border routers? If tcpdump could then extract this informaton (which could only be forged by a very small minority of people on the network) tracing such attacks woukd a be a lot easier... I suppose adding that info into teh ip header would cause far too much load on the exit routers though? Regards, aid > Here's a breif snippit from just a minute ago: > > 12:19:13.494446 49.0.94.105.666 > 205.229.58.133.7: udp 1450 (ttl 244, id > 31674) > 12:19:13.504446 12.206.160.94.666 > 205.229.58.133.7: udp 1450 (ttl 244, > id 31675)
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