Hi, On Thu, Feb 26, 2004 at 06:20:01AM +0100, Jørgen Hovland wrote:
On Wed, Feb 25, 2004 at 10:23:48PM +0100, Jørgen Hovland wrote:
There are actually some people here doing exactly that: Sending packets with an unroutable source-ip - with totally "legit" reasons.
Could you be somewhat more specific about these "legit" reasons?
Well.. Generally any device that would like to send messages without the need of a reply, or not in need of a reply through the same transport method/layer or ip (kind of asynchronous communication).
No specific reason why these applications couldn't use "proper" source-IPs, even if not expecting a reply.
I could name some, but I think what you are looking for is this: Routers with a non-routed ip-address by choice or by nature. IX-prefix for instance. IPv6 applies here specially.
IXP prefixes can be non-routed, but *are* well-known and properly assigned. So bogon source filtering will (usually) NOT blackhole IXP prefixes (while excessive uRPF on upstream lines will).
Besides from that there are software taking advantage of it like our own little project AP2P, truly anonymous P2P.
Now this is an interesting problem indeed. You need to weigh the benefits of this (in comparision to things like encrypted P2P clouds that claim to bring anonymity as well) against the chances of non-trackable abuse. This is a tricky question. I have made my decision on that: our customers can do whatever they like - as long as they do it from IP addresses that are well-assigned to them (even if temporary). If they commit abuse, in whatever form, be it a virus infection or intentional hacking, they can be traced back, and can be made legally liable for any damage they cause (if necessary). Gert Doering -- NetMaster -- Total number of prefixes smaller than registry allocations: 58081 (57882) SpaceNet AG Mail: netmaster@Space.Net Joseph-Dollinger-Bogen 14 Tel : +49-89-32356-0 80807 Muenchen Fax : +49-89-32356-299