Question 1mediummulti select
Full question →mediummulti selectObjective-mapped
Which two statements accurately describe route summarization?
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
It can reduce the number of individual routes that must be advertised.
This is correct because summarization aggregates routes into fewer advertisements.
B
Best answer
It can help improve routing scalability by simplifying route information.
This is correct because fewer, broader routes can reduce control-plane complexity.
C
Distractor review
It forces every router to use only a default route.
This is wrong because summarization does not eliminate the use of more specific routes where needed.
D
Distractor review
It is the same thing as PAT overload.
This is wrong because summarization is a routing concept, not a NAT function.
E
Distractor review
It automatically encrypts routing updates.
This is wrong because summarization and encryption are separate topics.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is mistaking route summarization for default routing or NAT-related functions. Some candidates incorrectly believe summarization forces routers to use only a default route, which is false because summarization still advertises specific aggregated routes, not just a default. Others confuse summarization with PAT overload, a NAT feature unrelated to routing. Additionally, some think summarization automatically encrypts routing updates, which it does not. These misconceptions can lead to incorrect answers and misunderstandings about routing behavior in Cisco networks.
Technical deep dive
How to think about this question
Route summarization is a routing optimization technique that combines multiple contiguous network routes into a single, broader route advertisement. This reduces the size of routing tables and the volume of routing updates exchanged between routers, which is critical for maintaining efficient network performance and scalability. Summarization is commonly used in distance-vector and link-state routing protocols such as EIGRP and OSPF to aggregate routes at area boundaries or autonomous system edges. The decision to summarize routes depends on the network design and addressing scheme. A router performing summarization selects a summary address that encompasses all specific routes within a range, advertising this single route instead of multiple individual routes. This reduces routing overhead and simplifies route processing. Cisco routers support manual summarization on interfaces or routing process boundaries, and some protocols like EIGRP can perform automatic summarization at classful boundaries unless disabled. A common exam trap is confusing route summarization with default routing or NAT functions like PAT overload. Summarization does not force routers to use only default routes; it aggregates specific routes into broader prefixes. It also does not involve encryption of routing updates. Understanding these distinctions helps avoid misinterpreting summarization’s purpose and behavior in Cisco routing environments, ensuring accurate configuration and troubleshooting.
KKey Concepts to Remember
- Route summarization aggregates multiple specific routes into a single broader route advertisement to reduce routing table size.
- Cisco routers can perform manual route summarization on interfaces or routing boundaries to optimize routing updates.
- Summarization improves routing scalability by decreasing the number of routes advertised and simplifying routing information.
- Routing protocols like EIGRP and OSPF support route summarization to limit routing update scope and control-plane load.
- Route summarization does not force routers to use only a default route; it preserves more specific routes within the summary.
- Summarization is distinct from NAT functions such as PAT overload and does not involve encrypting routing updates.
- Proper summarization requires contiguous network addresses to create an effective summary route without routing conflicts.
- Incorrectly assuming summarization replaces all specific routes with a default route is a common exam mistake.
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?
Route summarization aggregates multiple specific routes into a single broader route advertisement to reduce routing table size.
What is the correct answer to this question?
The correct answer is: It can reduce the number of individual routes that must be advertised. — Route summarization combines multiple specific routes into a smaller number of broader advertisements. In plain language, it lets a router describe a group of networks with one shorter, more general route instead of announcing each one individually. This can reduce routing-table size and improve scalability. It can also reduce the amount of routing information that must be exchanged across certain boundaries. The wrong answers often confuse summarization with default routing or encryption. The two correct statements are the ones that preserve its aggregation and scaling purpose.
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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