Currently internet routing table is growing drastically and every ISP is looking to move ahead over IPv6. But what I think ISP really no needs to migrate the whole backbone over IPv6 because the core doesn’t have more than 5000 – 10000 routes in extreme conditions. Enabling IPV6 simply putting an extra overhead with OSPFv3 and really cumbersome to memorize the schema. So it’s very difficult for operations to troubleshoot the problems with no time.
Customers can use the IPv6 but BGP 6VPE is the best solution to provide the MPLS services or vrf nat also works for same.
Till the time organizations are thinking of rolling out IPv6 services. But after watching LISP video I got feel good factor that Cisco Engineers are doing great job to stop the depletion of increasing routing table. Farinacci along with team has proposed the LISP solution so that the internet routing table could be decrease. Currently internet is having approx 288000 routes and increasing day by day.
LISP stands for LOcator/ID Separation Protocol which will help us to reduce the internet routing table size. But still it is in the deployment phase and everyone is waiting eagerly. As per LISP architecture designers will add a new network layer underneath the network layer, in other terms one can say it’s like encapsulation, legacy of Cisco. Currently every source is having information of every destination consequence internet routing table size increases. Hopefully we will be getting LISP in the coming years.