Which three routing characteristics are relevant for DMVPN Phase 3? (Choose three.)
Click on the arrows to vote for the correct answer
A. B. C. D. E. F.ACD.
DM VPN (Dynamic Multipoint Virtual Private Network) is a Cisco technology that provides a scalable and cost-effective solution for connecting remote sites with a hub site over the public internet. DM VPN Phase 3 is the latest version of DM VPN, which offers many new features and improvements over the previous versions.
The three routing characteristics that are relevant for DM VPN Phase 3 are:
B. Hubs must preserve the original IP next-hop: In DM VPN Phase 3, the hub router preserves the original IP next-hop address in the packet header when forwarding packets to the spokes. This is important because it allows the spoke routers to use their own routing tables to determine the best path to reach the final destination. If the hub router were to replace the original IP next-hop address with its own IP address, the spoke routers would be forced to use the hub router as the next-hop for all traffic, which could cause suboptimal routing and increased latency.
E. Spokes are routing neighbors with hubs and other spokes: In DM VPN Phase 3, the spokes are configured as routing neighbors with both the hub router and other spokes. This allows the spokes to exchange routing information with each other, which improves the overall scalability and efficiency of the network. In addition, DM VPN Phase 3 supports spoke-to-spoke communication, which means that two spokes can communicate directly with each other without having to go through the hub router.
F. Hubs are routing neighbors with other hubs and must use the same routing protocol as that used on hub-spoke tunnels: In DM VPN Phase 3, the hub routers are also configured as routing neighbors with each other, and they must use the same routing protocol as that used on the hub-spoke tunnels. This ensures that all routers in the network have consistent and up-to-date routing information, which is essential for proper network operation. In addition, DM VPN Phase 3 supports multiple hub routers, which provides redundancy and improves network availability.
C. Split-horizon must be turned off for RIP and EIGRP: In DM VPN Phase 3, split-horizon must be turned off for RIP (Routing Information Protocol) and EIGRP (Enhanced Interior Gateway Routing Protocol). Split-horizon is a feature that prevents a router from advertising a route back out of the same interface on which it was learned. In a DM VPN network, this can cause routing loops and suboptimal routing. By turning off split-horizon for RIP and EIGRP, the routers can exchange routing information more efficiently and accurately.
A. Hubs must not preserve the original IP next-hop: This statement is incorrect for DM VPN Phase 3. As mentioned earlier, the hub router must preserve the original IP next-hop address in the packet header when forwarding packets to the spokes.
D. Spokes are only routing neighbors with hubs: This statement is incorrect for DM VPN Phase 3. As mentioned earlier, the spokes are configured as routing neighbors with both the hub router and other spokes.
In conclusion, DM VPN Phase 3 offers many new features and improvements over the previous versions, including support for spoke-to-spoke communication, multiple hub routers, and improved routing efficiency and scalability. The three routing characteristics that are relevant for DM VPN Phase 3 are hub preservation of the original IP next-hop, spokes as routing neighbors with hubs and other spokes, and hubs as routing neighbors with other hubs using the same routing protocol.