Le 21 janv. 2010 à 08:42, Xu Xiaohu a écrit :
> > +------------------------+ > | | > | | > | IPv6 Internet | > | | > +------+----------+------+ > | | > | | > +--+--+ +--+--+ > +---+6rd-A+-----+6rd-B+--+ > | +-----+ +-----+ | > | | > | IPv4 ISP | > | +-------+ | > +-------+ CPE-1 +--------+ > +---+---+ > | > +-----+-----+ > | | > | IPv6 Site | > +-----------+ > > In the above scenario, two 6rd BRs are configured with the same address for > anycast service. Assuming the nearest 6rd BR for the CPE is 6rd-A, all IPv6 > packets from the IPv6 site and destined to the IPv6 internet will be > tunneled towards 6rd-A by the CPE. Once 6rd-A lost connections to the IPv6 > Internet, some failover mechanism should be used to direct these packets > towards 6rd-B. > One possible solution is: 6rd-A withdraws the route to the > IPv6 Internet, which was advertised in IPv4 ISP network previously, as soon > as its connection to the IPv6 Internet is lost. This is in my understanding the right solution, precisely because protection against routing loops can be achieved by preventing tunnels between BRs. > Another solution is: > establish a softwire tunnel between the two 6rd BRs for failover route. With > the latter solution, some normal packets tunneled in the softwire during > failover will be filtered mistakenly. That's why the other solution should be preferred. RD _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
