The IPv6 infrastructure we started with took advantage of the fact that the University’s core network uses VLAN technology extensively. This way we were able to add an IPv6 router independent from the rest of the IPv4 infrastructure. Therefore no harm could be done to running IPv4, be it the danger of higher resource usage (like CPU power) or caused by the necessity to use experimental IOS versions.

So we placed a dedicated Cisco 7206 router next the IPv4 infrastructure (see Figure 13-2). It is connected to the upstream network 6WiN via an IPv6-in-IPv4-Tunnel. It gets access to every VLAN we want to provide IPv6 services to. This IPv6 traffic is routed through the dedicated router and IPv4 uses the production network.

Management of the IPv6 network is limited. However, as it mainly consists of a single router, it is not so complex to monitor. We use mainly Argus and MRTG to obtain and visualize the network status.

Only a few VLANs are integrated into the IPv6 network. To give the user the opportunity to use IPv6, we offer most of the key services (DNS, Web, FTP, SMTP, NTP, NNTP, jabber, etc.) with dedicated servers we setup over time during the projects lifetime.