Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
What is the main purpose of route summarization in a routed network?
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
To combine multiple routes into a smaller set of broader advertisements
This is correct because summarization reduces and simplifies route information by aggregating prefixes.
B
Distractor review
To force every subnet to use the default route only
This is wrong because summarization does not mean all traffic must use only the default route.
C
Distractor review
To assign IP addresses dynamically to routers
This is wrong because DHCP handles dynamic addressing, not route summarization.
D
Distractor review
To convert access ports into trunks
This is wrong because summarization is a routing concept, not a switchport mode feature.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting answers that confuse route summarization with unrelated networking functions, such as dynamic IP address assignment or switchport mode changes. For example, options mentioning DHCP or trunk ports may seem plausible to candidates unfamiliar with routing concepts. The trap lies in misunderstanding that route summarization only aggregates routing prefixes to reduce routing table size and does not affect IP address assignment or Layer 2 switchport configurations. Recognizing this distinction is crucial to avoid selecting incorrect options that describe unrelated network operations.
Technical deep dive
How to think about this question
Route summarization is a routing technique that aggregates multiple contiguous network prefixes into a single, broader advertisement. This reduces the number of routes a router must maintain and advertise, which simplifies the routing table and decreases routing protocol overhead. Summarization is especially useful in hierarchical network designs where multiple subnets can be represented by a single summary route, improving scalability and efficiency. In Cisco routing protocols such as OSPF and EIGRP, route summarization is configured to advertise a summarized route instead of multiple specific routes. This reduces the size of routing updates and limits the propagation of routing changes, which helps stabilize the network. The router chooses to advertise the summary route when it has routes that fall within the summarized range, effectively hiding the more specific routes from other routers. A common exam trap is confusing route summarization with unrelated concepts like DHCP or switchport configurations. Route summarization does not assign IP addresses or change switchport modes; it strictly deals with routing information aggregation. Practically, improper summarization can cause routing black holes if the summary route covers addresses not actually reachable, so careful planning is essential in real networks.
KKey Concepts to Remember
- Route summarization combines multiple contiguous network prefixes into a single broader route advertisement to reduce routing table size.
- Cisco routing protocols such as OSPF and EIGRP use summarization to limit routing update size and improve network stability.
- Summarization helps reduce routing protocol overhead by decreasing the number of individual routes exchanged between routers.
- A router advertises a summary route only when it has specific routes that fall within the summarized address range.
- Route summarization does not assign IP addresses dynamically; that function is handled by DHCP, not routing protocols.
- Summarization is unrelated to switchport configurations and does not convert access ports into trunk ports.
- Improper summarization can cause routing black holes if the summary route includes unreachable addresses.
- Effective summarization improves network scalability by simplifying routing information and reducing routing churn.
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 combines multiple contiguous network prefixes into a single broader route advertisement to reduce routing table size.
What is the correct answer to this question?
The correct answer is: To combine multiple routes into a smaller set of broader advertisements — Route summarization combines multiple more-specific routes into a smaller set of broader advertisements. In plain language, it helps reduce routing-table size and can simplify the information routers exchange with each other. This can improve scalability and reduce churn because the network does not need to advertise every small route individually when a broader summary is appropriate. Summarization is not about creating VLAN tags or assigning DHCP leases. It is a routing design technique used to make route information more compact and manageable.
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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