North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: If you have nothing to hide
> > > > > Validation of routing policy to ensure others aren't abusing you (pointing > > default, for example). As for orders of magnitude, once an IP option is > > in a packet, the damage is essentially done, otherwise looking up the > > path to an address in the options is no more impactive than looking up the > > address in the original destination field. > > Well, no. Not really. > First off, following the 80/20 rule (or in this case 99.x/(100-99.x) > rule) says that hardware implementations which get optioned packets > punt them to software. This is at every hop. > > Second, the IP source route is a stack of IP addresses, which must be > modified at every hop. This implies not just software forwarding, but > also significantly more work than an IP lookup. As I said, once the option is in the packet, the damage is done. If the performance sucks for the person using the source-routing, who cares, assuming packets without IP options are forwarded without delay. If I'm not mistaken, most (if not all) vendors still punt the packets with source-routing options to software, even if they end up dropping the packet due to administrative decision. > eric
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