Cisco 642-902 Online Practice Questions and Exam Preparation

Cisco 642-902 Online Questions & Answers

• Question 281:

  Refer to the exhibit.

  

  Which statement about dynamic routing protocols for this network is true?

  A. No dynamic interior routing protocol can summarize as shown.
  B. Unless configured otherwise, EIGRP would automatically summarize the prefixes as shown in the exhibit.
  C. With this IP addressing scheme, EIGRP can be manually configured to summarize prefixes at the specified summarization points.
  D. The IP address design lends itself to OSPF. Each summarizing router would be an ABR, summarizing to the next area in the address hierarchy.
  C. With this IP addressing scheme, EIGRP can be manually configured to summarize prefixes at the specified summarization points.

  ---

  Summarization may be manually applied at any point in the network. You can configure manual summarization on any router interface. Consider summarization for both upstream and downstream neighbors. Upstream neighbors should receive a consolidated route, and downstream neighbors can receive a default route.

• Question 282:

  Which command displays the number of times that the OSPF Shortest Path First (SPF) algorithm has been executed?

  A. show ip protocol
  B. show ip ospf
  C. show ip ospf database
  D. show ip ospf interface
  B. show ip ospf

  ---

  The following table describes the output of the "show ip ospf" command and their meanings: Table52 show ip ospf Field Descriptions

  

  Reference:http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123cgcr/iprrp_r /ip2_s3g.htm#wp1036469

• Question 283:

  Which two conditions can cause BGP neighbor establishment to fail? (Choose two.)

  A. There is an access list blocking all TCP traffic between the two BGP neighbors.
  B. The IBGP neighbor is not directly connected.
  C. BGP synchronization is enabled in a transit autonomous system with fully-meshed IBGP neighbors.
  D. The BGP update interval is different between the two BGP neighbors.
  E. The BGP neighbor is referencing an incorrect autonomous system number in its neighbor statement.
  A. There is an access list blocking all TCP traffic between the two BGP neighbors.
  E. The BGP neighbor is referencing an incorrect autonomous system number in its neighbor statement.

  ---

  BGP uses TCP port 179 to establish and maintain neighbor relationships, so any access lists or firewalls must permit this port for BGP to function. By default, EBGP multi-hop is not enabled, so the EBGP peer must be directly connected in order for the local BGP router to know how to reach the EBGP peer. BGP uses neighbor statements that specify the AS number of the BGP peer. If it is the same number as the local BGP router process, then the BGP router knows that IBGP is used. If the AS number for the specified peer is different, then EBGP is used. Either way, the specified neighbor must be configured correctly, or the BGP peers will not become neighbors.

• Question 284:

  Which two methods use IPsec to provide secure connectivity from the branch office to the headquarters office? (Choose two.)

  A. DMVPN
  B. MPLS VPN
  C. Virtual Tunnel Interface (VTI)
  D. SSL VPN
  E. PPPoE
  A. DMVPN
  C. Virtual Tunnel Interface (VTI)

  ---

  Reference: http://www.ccnpguide.com/ccnp-route-642-902-vpns-and-ipsec/

• Question 285:

  A network administrator recently redistributed RIP routes into an OSPF domain. However, the administrator wants to configure the network so that instead of 32 external type-5 LSAs flooding into the OSPF network, there is only one.

  

  What must the administrator do to accomplish this?

  A. Configure summarization on R1 with area 1 range 172.16.32.0 255.255.224.0
  B. Configure summarization on R1 with summary-address 172.16.32.0 255.255.224.0
  C. Configure area 1 as a stub area with area 1 stub
  D. Configure area 1 as a NSSA area with area 1 stub nssa
  B. Configure summarization on R1 with summary-address 172.16.32.0 255.255.224.0

  ---

  In many cases, the router doesn't even need specific routes to each and every subnet (for example, 172.16.1.0/24). It would be just as happy if it knew how to get to the major network (for example, 172.16.0.0/16) and let another router take it

  from there. In our telephone network example, the local telephone switch should only need to know to route a phone call to the switch for the called area code. Similarly, a router's ability to take a group of subnetworks and summarize them as

  one network (in other words, one advertisement) is called route summarization. Besides reducing the number of routing entries that a router must keep track of, route summarization can also help protect an external router from making

  multiple changes to its routing table due to instability within a particular subnet. For example, let's say that we were working on a router that connected to 172.16.2.0/24. As we were working on the router, we rebooted it several times. If we

  were not summarizing our routes, an external router would see each time 172.16.2.0/24 went away and came back. Each time, it would have to modify its own routing table. However, if our external router were receiving only a summary route

  (i.e., 172.16.0.0/16), then it wouldn't have to be concerned with our work on one particular subnet. This is especially a problem for EIGRP, which can create stuck in active (SIA) routes that can lead to a network melt-down.

  Summarization Example

  We have the following networks that we want to advertise as a single summary route:

  *

  172.16.100.0/24

  *

  172.16.101.0/24

  *

  172.16.102.0/24

  *

  172.16.103.0/24

  *

  172.16.104.0/24

  *

  172.16.105.0/24

  *

  172.16.106.0/24

• Question 286:

  What are three reasons to control routing updates via route filtering? (Choose three).

  A. to hide certain networks from the rest of the organization
  B. for easier implementation
  C. to control network overhead on the wire
  D. for simple security
  E. to prevent adjacencies from forming
  A. to hide certain networks from the rest of the organization
  C. to control network overhead on the wire
  D. for simple security

  ---

  Route filtering hide certain networks from the rest of the organization and it also controls network overhead. Not only this, it also provides security to the routing updates.

• Question 287:

  A network administrator is troubleshooting an EIGRP connection between RouterA, IP address 10.1.2.1, and RouterB, IP address 10.1.2.2.

  

  Given the debug output on RouterA, which two statements are true?

  A. RouterA received a hello packet with mismatched autonomous system numbers.
  B. RouterA received a hello packet with mismatched hello timers.
  C. RouterA received a hello packet with mismatched authentication parameters.
  D. RouterA received a hello packet with mismatched metric-calculation mechanisms.
  E. RouterA will form an adjacency with RouterB.
  F. RouterA will not form an adjacency with RouterB.
  D. RouterA received a hello packet with mismatched metric-calculation mechanisms.
  F. RouterA will not form an adjacency with RouterB.

  ---

  If the k-value mismatch occurs, Router A will never form an adjacency with Router B since it is one of the basic requirements of adjacency. If you see the exhibit, Router A received HELLO packet with a mismatched metric.

• Question 288:

  How is network layer addressing accomplished in the OSI protocol suite?

  A. Internet Protocol address
  B. Media Access Control address
  C. Packet Layer Protocol address
  D. Network Service Access Point address
  E. Authority and Format Identifier address
  D. Network Service Access Point address

  ---

  OSI network-layer addressing is implemented by using two types of hierarchical addresses: network service access-point addresses and network-entity titles.

  A network service-access point (NSAP) is a conceptual point on the boundary between the network and the transport layers. The NSAP is the location at which OSI network services are provided to the transport layer. Each transport-layer entity is assigned a single NSAP, which is individually addressed in an OSI internetwork using NSAP addresses.

• Question 289:

  When implementing a 6to4 tunnel, which IPv6 address is the correct translation of the IPv4 address 192.168.99.1?

  A. c0a8:6301:2002::/48
  B. 2002:c0a8:6301::/48
  C. 2002:c0a8:6301::/8
  D. 2002::/16
  B. 2002:c0a8:6301::/48

  ---

  16 bits for the most significant 6to4 reserved bits (2002::/16) plus 32 bits source ipv4 address (traslated in HEX format) = 48 bits, Topic 5: Implement an IPv4 or IPv6 based redistribution solution, given a network design and a set of requirements

• Question 290:

  Refer to the exhibit.

  

  There are two eBGP links between AS100 and AS200. Currently the router A to router E link has an average inbound load of 65% and the router B to router F link has an average inbound load of 20%. After further investigation, it is found that traffic to the 10.10.1.16/28 subnet is using 45% of the bandwidth on the A to router E link and traffic to the 10.10.1.32/28 subnet is using 20% of the bandwidth on the A to router E link. Traffic to the 10.10.1.48/28 subnet is using 20% of the bandwidth on the B to router F link. If you want to influence how AS200 sends traffic to AS100, which two commands would you configure in AS100 to influence AS200 to use the eBGP links more evenly? (Choose two.)

  A. neighbor 192.168.30.2 route-map as_50 out
  B. neighbor 192.168.20.2 route-map as_50 out
  C. route-map as_50 permit 10 match ip address 50 set metric 150 access-list 50 permit 10.10.1.16 0.0.0.240
  D. route-map as_50 permit 10 match ip address 50 set metric 150 access-list 50 permit 10.10.1.32 0.0.0.15
  A. neighbor 192.168.30.2 route-map as_50 out
  D. route-map as_50 permit 10 match ip address 50 set metric 150 access-list 50 permit 10.10.1.32 0.0.0.15