On Thu, Nov 7, 2013 at 7:40 PM, Hermin Anggawijaya <[email protected]> wrote: >> I'm seeing plenty of packets from link-local sources to global >> destinations >> ..... > >> 2) routers on the Internet do forward such packets (violating the rule >> mentioned above). >> Fixing #2 actually requires making forwarding decision based on src >> and dst (which is not happening now). > > To fix the above issue, wouldn't address scope checking be enough, rather > than the [src,dst] based routing > discussed ?
My point is that to do verify the scope, the router need to check *source* address while making forwarding decision. It looks like it is not happening now but it might get changed by [src, dst] based routing. > On Thu, Nov 7, 2013 at 8:58 AM, Jen Linkova <[email protected]> wrote: >> >> On Thu, Nov 7, 2013 at 5:45 PM, Fred Baker (fred) <[email protected]> wrote: >> > Examples of use cases are generally around multi-prefix campus networks. >> > There is a security use case that could be of value; at IETF 87, George >> > Michaelson of APNIC reported on ULAs seen in his darknet. The short report >> > is that he sees a fair bit of traffic with a ULA source address on the >> > backbone. An interesting potential use of source/destination routing would >> > counter that, and perhaps mitigate the need for ISP BCP 38 if generally >> > deployed; in a case where a network is using a ULA and a global prefix >> > (e.g., is not multihomed but has two prefixes, one of which is intended to >> > only be used within its network), the default route to the network egress >> > would use the global prefix as a source, and as a result traffic sent >> > outside the network with a ULA source prefix would in effect have no route. >> > The network could literally only emit traffic from its correct prefix. >> >> Looks like we (finally) have a chance to enforce the requirement from >> RFC4007, Section9: >> >> "If transmitting the packet on the chosen next-hop interface >> would cause the packet to leave the zone of the source >> address, i.e., >> cross a zone boundary of the scope of the >> source address, then the packet is discarded. " >> >> I'm seeing plenty of packets from link-local sources to global >> destinations which means that: >> 1) there are hosts with broken default address selection >> AND >> 2) routers on the Internet do forward such packets (violating the rule >> mentioned above). >> Fixing #2 actually requires making forwarding decision based on src >> and dst (which is not happening now). >> >> More data (sorry, shameless plug :)) >> https://ripe67.ripe.net/presentations/288-Jen_RIPE67.pdf >> >> -- >> SY, Jen Linkova aka Furry >> _______________________________________________ >> v6ops mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/v6ops > > -- SY, Jen Linkova aka Furry _______________________________________________ rtgwg mailing list [email protected] https://www.ietf.org/mailman/listinfo/rtgwg
