Abstract:
This study investigates the potential benefits and challenges of using layer 3 Internet Protocol version 6 (IPv6) configuration commands. Although any other type of layers 3 devices could have been used in this study, only Cisco routers and multilayer switches are considered. The study is conducted using a simulator called Graphical Network Simulator-3 (GNS3). Even though real Cisco Internetwork Operating System (IOS) software is reliably used in this simulator, an avoidable limitation of this method involves not using this software on real routers and multilayer switches. However, it has been found that contrary to Cisco documentation, using the outgoing local interface as next hop address causes IPv6 static routing not to work; it only works when the neighbouring global unicast address is used as the next hop address. Other findings show that when static addresses are configured with Routing Information Protocol Next Generation (RIPng), Enhanced Interior Gateway Routing Protocol version 6 (EIGRPv6) or Open Shortest Path First version 3 (OSPFv3), RIPng has the best round-trip time (RTT), while OSPFv3 gives the best traceroute results. Likewise, 64-bit Extended Unique Identifier (EUI-64) addresses produce better RTT and traceroute results with RIPng than with EIGRPv6 and OSPFv3. Nonetheless, one challenge for RIPng involves failure to start the RIPng process by misconfiguring the ipv6 router rip name and ipv6 rip name enable commands. The benefit of EIGRPv6 is that its RTT is faster than that of OSPFv3 and even if the router identifiers (router-ids) are configured the same on all the routers, the EIGRPv6 process still works well. However, configuring different autonomous system numbers and failing to configure the "no shutdown" or router-id commands results in routing challenges. On the other hand, configuring the same router-id on different layer 3 devices causes OSPFv3 not to work. In spite of this challenge, when OSPFv3 is used with Hot Standby Router Protocol version 2 (HSRPv2), it generates faster RTT than EIGRPv6 and RIPng. However, the success rate of OSPFv3 for failover time of the active router to the standby router is 4% lower than EIGRPv6. In comparison to Internet Protocol version 4 (IPv4), configuring of static and EUI-64 address commands is a very challenging task, because of the hexadecimal nature of IPv6 addresses. Despite this challenge, one benefit of these commands is the ability to use slash notation such as /64 for the prefix length. When used on dual stack commands, static addresses give better native router processing performance with no encapsulation overheads. However, configuring these addresses on dual stack commands in large networks is a challenge. With regard to manual IPv6 tunnelling, configuring the tunnel interface addresses in the same network and failure to configure the tunnel mode ipv6ip command, prevents this technique from working. Although IPv6 static Network Address Translation-Protocol Translation (NAT-PT) commands are easy to configure and to troubleshoot, the NAT-PT router raises the challenge of being a single point of failure in the network. On the whole, given these benefits and challenges, implementing IPv6 in industrial networks should not be scary. The results of this study are useful guidelines on how to efficiently design and configure IPv6 networks in a smooth way.
