Networking Requirements As shown in Figure 1, two IPv6 networks are connected to Device B on the IPv4 backbone network through Device A and Device C. To interconnect the two IPv6 networks, configure a manual IPv6 over IPv4 tunnel between Device A and Device C. Figure 1 Configuring a manual IPv6 over IPv4 tunnel   Precautions When configuring a manual IPv6 over IPv4 tunnel, note the following …