English
Menu

Network Design and Operations

Branch router R2 is connected to head-office router R1 over a 10.255.0.0/30 link, with R1's end at 10.255.0.1 and R2's at 10.255.0.2. When a static route to the head-office network 192.168.1.0/24 is configured on R2, which address is appropriate as the next hop?

  1. A10.255.0.1
  2. B10.255.0.2
  3. C192.168.1.1 (R1's address on the head-office LAN)
Show answer and explanation

Answer: A. 10.255.0.1

A static route specifies the destination network and the address of the next router to hand packets to (the next hop). As a rule, the next hop is the address of a neighboring router on a network to which the router is directly connected. Here it is R1's address on the other end of the link, 10.255.0.1, and R2 uses ARP to find the MAC address for it before sending frames. When a branch has only one way out, a common alternative to writing a route for each destination is to configure just one default route, 0.0.0.0/0.

  • A. Correct. It is the address of R1, the directly connected neighbor router.
  • B. This is R2's own address, so it cannot be the next router to hand packets to.
  • C. This address is not on a network directly connected to R2, and R2 has no route to it, so it cannot be used as the next hop.
Practice this topic Back to topic

Related calculators

IP address and subnet calculatorFind the network and broadcast addresses, host range and host count from an IP address and a prefix or mask, with a binary view and subnet splittingDijkstra's algorithm calculatorCompute shortest paths and distances from a list of weighted edges, and follow each step of finalizing vertices in a table and a diagram

Books on Network Design and Operations Ad

As an Amazon Associate I earn from qualifying purchases.

More Network Design and Operations questions

  1. A router has learned routes to the same destination, 192.168.50.0/24, from both OSPF and RIP. On this router, the administrative distance, which expresses the preference for each route source (lower is preferred), is 110 for OSPF and 120 for RIP. Which route goes into the routing table?
  2. A router's routing table holds three routes: a static route 10.0.0.0/8 (next hop router A, administrative distance 1), 10.1.0.0/16 learned by OSPF (router B, 110) and 10.1.1.0/24 learned by RIP (router C, 120). To which router is a packet for 10.1.1.5 sent?
  3. Which statement correctly describes a link-state routing protocol?
  4. In OSPF, router R1 has three paths to a network beyond R4. Path A uses a 10 Gbps link R1–R5 and a 1 Gbps link R5–R4; path B is a direct 100 Mbps link R1–R4; and path C uses 1 Gbps links R1–R2, R2–R3 and R3–R4. The cost of each link is "reference bandwidth 10 Gbps ÷ link bandwidth", and the cost beyond R4 is the same for all paths. Which path does R1 choose?
  5. On the internet, which protocol exchanges routing information between the networks run by organizations such as ISPs (ASes, autonomous systems) and chooses routes based on attributes such as the sequence of ASes a route has passed through (AS_PATH) and on each organization's policy?

Comparisons in this topic