Question 1.
According to the following exhibit, company 1 contains two autonomous systems (AS1 and AS2) connected via ISP A, which has an AS number of 100. Router B and Router C are advertising an aggregate of X.X.X.0/23 so that AS1 is able to reach the two server farms. The two links from AS2 are not being used efficiently.

How can AS2 use both of the links coming into it?
Exhibit:
 

A. advertise each X.X.X.0/24 independently from Router B and Router C
B. create another link between Router A in AS1 and ISP A
C. configure iBGP between Router B and Router C to load-share traffic once it reaches AS2
D. configure two static routes in Router A for X.X.X.0/23 pointing to Router B and Router C

Answer: A

Question 2.
Study the topology provided in this exhibit. Which configuration change will maximize the efficiency of both the routing design and data forwarding plane?
Exhibit:
 

A. Configure Router B with a static route for the aggregate to Null0
B. Configure Router A to advertise 10.0.0.0/8 instead of the default route to Router B
C. Configure Router B to advertise the more specific prefixes in addition to the aggregate
D. Configure Router B to advertise the more specific prefixes instead of the aggregate

Answer: A

Explanation:
Null0 is an interface that doesn’t exist. The null0 interface can be used with static routes to route a packet into a black hole of sorts. In other words, if you have traffic that you do not want to reach a particular destination, you can create the static route for that destination with the next-hop interface pointing to null0. Any traffic that enters the Router destined for the network specified in the static route will be sent to the null0 interface and dropped.

When working with classless and classful routing, you should crate a static route with the classful variant of the classless route and point it to interface null0.
Example: ip route 10.0.0.0 255.0.0.0 null0

Question 3.
Which two reasons are valid for aggregating routing information within a network? (Choose two)

A. To reduce the amount of information any specific Router within the network must store and 
    process
B. To isolate the impact of DDoS attacks
C. To improve optimal routing within the network
D. To reduce the impact of topology changes

Answer: A, D

Explanation:
Route aggregation, or route summarization, is the process of advertising a single route for multiple routes. This is useful in limiting the number of routes that will be stored in a routing table, thus cutting down on the amount of memory and processing power required.

Question 4.
Which three statements are correct about OSPF route summarization? (Choose three.)

A. Route summarization can lead to a more stable network.
B. A flat addressing scheme is required in order to summarize OSPF routes.
C. OSPF type 5 external routes can be summarized only at the ASBRs.
D. OSPF internal routes can be summarized only at the ABRs.

Answer: A, C, D

Explanation:
Route summarization is the consolidation of multiple routes into a single route for better performance. It is also the key of scalability in OSPF because it reduces LSA flooding and Link State Database and routing table sizes, which reduces memory and CPU utilization on the Routers. In OSPF environment either we can summarize routes in ASBR or ABR. ASBR can summarize the external routes and ABR can summarize internal routes between Area.
Example:
Inter-Area Route summarization:
Router(Config)#Router ospf 1
Router(Config-Router)#Area area-id range address mask
External Route Summarization:
Router(Config)#Router ospf 1
Router(Config-Router)#summary-address ip mask

Question 5.
EIGRP performs route summarization at the interface level with the “ip summaryaddress” command. 

Which three statements correctly describe EIGRP route summarization? (Choose three)

A. By default, EIGRP automatically summarizes internal routes, but only each time a major 
    network boundary is crossed.
B. EIGRP route summarization can reduce the query diameter to help prevent SIA problems.
C. Summary routes are inserted in the routing table with a next hop of null 0 and a high 
    administrative distance, to prevent black holing of traffic.
D. The metric for each summarized route is inherited from the lowest metric of the component 
    routes.

Answer: A, B, D

Question 6.
Why build link state flooding domain boundaries in large-scale networks running OSPF or IS-IS? (Choose two.)

A. Doing so provides logical break points at which to troubleshoot individual parts of the network, 
    rather than trying to troubleshoot the whole network at once.
B. Doing so limits the extent of SPF and allows the use of PRC for some best path calculations.
C. Flooding domain borders block the transmission of external routing information in the network, 
    which improves scaling and convergence times.
D. Network administrators can quickly find specific destinations when detailed link state 
    information is sorted by flooding domain in the link state database.

Answer: A, B

Question 7.
Which two options are true about the impact flooding domain boundaries have when built in OSPF? (Choose two)

A. They decrease convergence time by reducing the complexity and size of the shortest path 
    trees in the individual areas.
B. They isolate network failures within a domain.
C. They decrease convergence time by automatically summarizing reachability information 
    transmitted through the network, thereby decreasing the number of routes that must be 
    installed in each Router's routing table.
D. They increase convergence time by adding the time required to run two full Shortest Path First 
    computations on the area border Routers.

Answer: A, B

Question 8.
Which two reasons are correct about building a flooding domain boundary in a link-state network? (Choose two.)

A. To provide an administrative boundary between portions of the network
B. To segregate complex and rapidly changing portions of the network from one another
C. To aggregate reachability information
D. To increase the size of the Shortest Path First tree

Answer: B, C

Explanation:
Low-speed links and large numbers of spokes may require multiple flooding domains or areas to be supported effectively. You should balance the number of flooding domains on the hub against the number of spokes in each flooding domain. The link speeds and the amount of information being passed through the network determine the right balance. Design for these situations must balance the number of areas and the Router impact of maintaining an LSA database and doing Dijkstra calculations per area against the number of remote Routers in each area

Question 9.
What are three reasons to summarize link state topology information? (Choose three)

A. To reduce the amount of routing information being advertised
B. To create boundaries for containing potential network changes and instabilities
C. To permit traffic engineering between areas
D. To hide detailed topology information

Answer: A, B, D

Explanation:
Route summarization is the consolidation of multiple routes into a single route for better performance. It is also the key of scalability in OSPF because it reduces LSA flooding, Link State Database and routing table sizes, which reduces memory and CPU utilization on the Routers.

Question 10.
Scalability is provided in the server farm module by which of the following design strategies?

A. Redundant servers at the access level
B. High port densities at the access level
C. Modular block design at the access level
D. Up to 10 Gbps of bandwidth at the access level

Answer: C

Explanation:
The primary objectives in the design of a large-scale, shared-enterprise server farm are: 
• Performance— Up to 10 Gbps outbound bandwidth capacity is required from the server farm for most enterprises.
• Scalability— A critical requirement in every server farm. Server load balancing is most often deployed. As the number of servers requiring higher-bandwidth connections increases, port densities can exceed the capacity of a single switch or server farm block. Applying a modular block design to server farm deployments permits flexible growth.
• Availability— Availability is generally ensured through the overall network design. Networks are designed to minimize the occurrence of service problems and the time to recover from problems, for example, with backup recovery policies and procedures.
• Security— Security is an integral part of the network design. A single vulnerability could compromise the enterprise. Specialized security expertise is often required.
• Manageability— Manageability means much more than knowing if a server or other network element is up or down. Good manageability tools and qualified personnel lower operations costs and reduce wasted time, and they yield higher overall satisfaction.

Reference: 
CCDP Self-Study: Designing Cisco Network Architectures (ARCH) by Keith Hutton; Amir Ranjbar

	Web www.certsbraindumps.com