"portscans" (was Re: Arbor Networks DoS defense product)
Ralph Doncaster
ralph at istop.com
Sun May 19 16:13:35 UTC 2002
> RD> I think that's pretty stupid. If I had my network admin investigate every
> RD> portscan, my staff costs would go up 10x and I'd quickly go bankrupt.
> RD> Instead we keep our servers very secure, and spend the time and effort
> RD> only when there is evidence of a break in.
>
> I didn't say investigate every portscan, I said assume every portscan
> is hostile. There is a big difference.
So you assume it's hostile and do what? Automatically block the source
IP? If you do that then you open up a bigger DOS hole. Then if someone
sends a bunch of SYN scans with the source address spoofed as your
upstream transit providers' BGP peering IP, poof! you're gone.
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