Overview ofOSPFv3 and IS–IS OSPFv3 and IS–IS are link state protocols and have some similarities butdiffer inrouting behavior. Both protocols use the same routing algorithm todetermine the shortest paths to all destinations within a network. While OSPFwas natively developed to route datagram in IP, IS–IS was natively developedfor ISO CLNS environments but was later adopted by IETF to support routing inIP (Kaur et al., 2014). Both routing protocols have now become popular due tothe widespread adoption of IP.15 Open shortestpath first version 3 (OSPFv3) OSPFv3 is the modified version of OSPF that is used to support routingin IPv6. InOSPFv3, some basic techniques used in OSPF are still maintained. Thesetechniques include designated router election, flooding, shortest path firstcalculation, and area support.
While these basic mechanisms are stillmaintained in OSPFv3, some necessary changes have also been introduced becauseof the difference in protocol structure between IPv4 and IPv6. (Coltum et al,2008). OSPF was developed by the IETF in 1987. The version now used in IPv4 isOSPFv2. It was published in RFC 2328.
OSPFv2 was later updated to OSPFv3 tosupport IPv6. OSPFv3 was release in 1999 and was published in RFC 5340. OSPFv3is a link state protocol which works by using Dijkstra’s algorithm to determinethe shortest path to a destination within a network. To determine the shortestpath to each destination, OSPFv3 first constructs a shortest path tree from thenetwork. The shortest path tree contains all pathsleading to remote networks. From the shortestpath tree, OSPFv3 then selects all resulting best paths and use them topopulate its routing table (Lammle, 2007).
OSPF supports hierarchical networkdesign, enabling network designers to separate larger networks into smallerones called Areas. Separating larger networks into areas minimizes the amountof routing information that can be propagated at a time. This reducesconvergence time of the network.
Also, when any fault occurs in the wholenetwork it can be traced to each area within the