Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
An IPv6 host has a global unicast address and a correct default route learned from a router advertisement, but the next-hop entry shown on the host uses a link-local address rather than a global unicast address. What is the best explanation?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
IPv6 hosts commonly use the router’s link-local address as the next hop on the local segment.
This is correct because IPv6 next-hop behavior often relies on the router’s link-local address on the local link.
B
Distractor review
The host has learned the wrong default route because IPv6 gateways must always be global unicast.
This is wrong because link-local next-hop use is normal in IPv6.
C
Distractor review
The host can reach only local destinations when the next hop is link-local.
This is wrong because link-local next-hop use still supports off-link forwarding through the local router.
D
Distractor review
The router advertisement has failed because it did not provide a MAC address.
This is wrong because the issue described is not an RA failure.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A common exam trap is believing that the next-hop address for an IPv6 default route must be a global unicast address. Many candidates incorrectly assume that because the destination is global, the next-hop must also be global. However, IPv6 standards specify that the next-hop on the local link is typically the router's link-local address. Misunderstanding this leads to confusion about routing tables and default gateway behavior, causing candidates to mark answers that claim the route is incorrect or the router advertisement failed. Recognizing that link-local next hops are normal prevents this mistake.
Technical deep dive
How to think about this question
IPv6 addressing includes several address types, with global unicast addresses used for routable communication across the internet and link-local addresses used for communication on the local network segment. When an IPv6 host receives a router advertisement, it learns the default gateway's address, which is often the router's link-local address. This is because the host only needs to forward packets to the router on the local link before they are routed onward. The link-local address uniquely identifies the router interface on the local segment without requiring a global address. The IPv6 routing process on a host uses the next-hop address to determine where to send packets destined for off-link addresses. Although the default route learned via router advertisement is global, the next-hop IP in the routing table is typically the router's link-local address. This is a design choice in IPv6 to ensure local link communication is efficient and unambiguous. The host sends packets to the router's link-local address, which the router then forwards appropriately. A common exam trap is assuming the next-hop must be a global unicast address because the destination is global. However, IPv6 standards specify that the next-hop for a default route on a local link is often the router's link-local address. This behavior is normal and expected. Practically, this means the host uses the router's link-local address for the immediate hop, while the router handles forwarding beyond the local network, ensuring proper routing without confusion or address conflicts.
KKey Concepts to Remember
- IPv6 hosts use link-local addresses to communicate with routers on the local link for next-hop forwarding.
- Router advertisements provide default routes with next-hop addresses that are often link-local rather than global unicast.
- The next-hop address in an IPv6 routing table points to the router's link-local address for local segment forwarding.
- IPv6 routing separates the concept of a global destination address from the next-hop address used for local delivery.
- Hosts forward packets to the router's link-local address, which then routes packets to global destinations.
- Using link-local addresses as next hops prevents ambiguity and ensures efficient local link communication in IPv6.
- IPv6 standards allow and expect the next-hop for default routes to be a link-local address on the local segment.
- Confusing the next-hop address type can lead to incorrect assumptions about IPv6 routing behavior and troubleshooting errors.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
IPv6 hosts use link-local addresses to communicate with routers on the local link for next-hop forwarding.
What is the correct answer to this question?
The correct answer is: IPv6 hosts commonly use the router’s link-local address as the next hop on the local segment. — That behavior is normal in IPv6. In practical terms, the host only needs to reach the router on the local segment, so it uses the router’s link-local address as the next-hop target. The packet still leaves the local link toward remote destinations, but the immediate neighbor on that link is identified by link-local addressing. This is an important IPv6 concept because many people assume the default gateway must be a globally routable address. It does not. On the local link, the host is really forwarding to its directly attached router interface, and the router’s link-local address is enough for that local handoff.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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