200-101 Interconnecting Cisco Networking Devices Part 2

Page 1   
Question 1

Which three statements are typical characteristics of VLAN arrangements? (Choose three.)

  • A. A new switch has no VLANs configured.
  • B. Connectivity between VLANs requires a Layer 3 device.
  • C. VLANs typically decrease the number of collision domains.
  • D. Each VLAN uses a separate address space.
  • E. A switch maintains a separate bridging table for each VLAN.
  • F. VLANs cannot span multiple switches.


Answer : B,D,E

Explanation: By default, all ports on a new switch belong to VLAN 1 (default & native VLAN). There are also some well-known VLANs (for example: VLAN 1002 for fddi-default; VLAN 1003 for token-ring) configured by default -> A is not correct. To communicate between two different VLANs we need to use a Layer 3 device like router or Layer 3 switch -> B is correct. VLANs dont affect the number of collision domains, they are the same -> C is not correct. Typically, VLANs increase the number of broadcast domains.We must use a different network (or sub-network) for each VLAN. For example we can use 192.168.1.0/24 for VLAN 1, 192.168.2.0/24 for VLAN 2 -> D is correct. A switch maintains a separate bridging table for each VLAN so that it can send frame to ports on the same VLAN only. For example, if a PC in VLAN 2 sends a frame then the switch look-ups its bridging table and only sends frame out of its ports which belong to VLAN 2 (it also sends this frame on trunk ports) -> E is correct. We can use multiple switches to expand VLAN -> F is not correct.

Question 2

Refer to the exhibit.


Which two statements are true about interVLAN routing in the topology that is shown in the
exhibit? (Choose two.)

  • A. Host E and host F use the same IP gateway address.
  • B. Router1 and Switch2 should be connected via a crossover cable.
  • C. Router1 will not play a role in communications between host A and host D.
  • D. The FastEthernet 0/0 interface on Router1 must be configured with subinterfaces.
  • E. Router1 needs more LAN interfaces to accommodate the VLANs that are shown in the exhibit.
  • F. The FastEthernet 0/0 interface on Router1 and the FastEthernet 0/1 interface on Switch2 trunk ports must be configured using the same encapsulation type.


Answer : D,F

Explanation: http://www.cisco.com/en/US/tech/tk389/tk815/technologies_configuration_example09186a 00800949fd.shtml

Question 3

Refer to the exhibit.


Given the output shown from this Cisco Catalyst 2950, what is the reason that interface
FastEthernet 0/10 is not the root port for VLAN 2?

  • A. This switch has more than one interface connected to the root network segment in VLAN 2.
  • B. This switch is running RSTP while the elected designated switch is running 802.1d Spanning Tree.
  • C. This switch interface has a higher path cost to the root bridge than another in the topology.
  • D. This switch has a lower bridge ID for VLAN 2 than the elected designated switch.


Answer : C

Explanation: These four parameters are examined in order to make root bridge , root port , designated port. Other switch has lowest Sending Bridge ID or Sending Port ID so vlan 2 is not the root port. 1. A lower Root Bridge ID2. A lower path cost to the Root3. A lower Sending Bridge ID4. A lower Sending Port ID Topic 2, IP Routing Technologies

Question 4

Which command is used to display the collection of OSPF link states?

  • A. show ip ospf link-state
  • B. show ip ospf lsa database
  • C. show ip ospf neighbors
  • D. show ip ospf database


Answer : D

Explanation: http://www.cisco.com/en/US/docs/ios/iproute_ospf/command/reference/iro_osp3.html#wp1 01217 Examples The following is sample output from the show ip ospf database command when no arguments or keywords are used: Router# show ip ospf database OSPF Router with id(192.168.239.66) (Process ID 300)

Question 5

Refer to the exhibit.


The network associate is configuring OSPF on the Core router. All the connections to the
branches should be participating in OSPF. The link to the ISP should NOT participate in
OSPF and should only be advertised as the default route. What set of commands will
properly configure the Core router?

  • A. Core(config-router)# default-information originate Core(config-router)# network 10.0.0.0 0.255.255.255 area 0 Core(config-router)# exit Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
  • B. Core(config-router)# default-information originate Core(config-router)# network 10.10.2.13 0.0.0.242 area 0 Core(config-router)# exit Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
  • C. Core(config-router)# default-information originate Core(config-router)# network 10.10.2.16 0.0.0.15 area 0 Core(config-router)# exit Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14
  • D. Core(config-router)# default-information originate Core(config-router)# network 10.10.2.32 0.0.0.31 area 0 Core(config-router)# exit Core(config)# ip route 0.0.0.0 0.0.0.0 10.10.2.14


Answer : C

Explanation: There are two ways to inject a default route into a normal area.1. If the ASBR already has the default route in its routing table, you can advertise theexisting 0.0.0.0/0 into the OSPF domain with the default-information originate router configuration command.2. If the ASBR doesnt have a default route, you can add the keyword always to the default- information originate command (default-information originate always).This command will advertise a default route into the OSPF domain, regardless of whether it has a route to 0.0.0.0. Another benefit of adding always keyword is that it can add stability to the internetwork. For example, if the ASBR is learning a default route from another routing domain such as RIP and this route is flapping, then without the always keyword, each time the route flaps, the ASBR will send a new Type 5 LSA into the OSPF domain causing some instability inside the OSPF domain. With the always keyword, the ASBR will advertise the default inside the OSPF domain always,In the example shown here, only choice C is correct as the wildcard mask correctly specifies the 10.10.2.16 0.0.0.15 networks, which include all IP addresses in the 10.10.2.16-10.10.2.31 range. In this question we were told that the ISP link should NOT be configured for OSPF, making choice A incorrect. http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00801 ec9f0.shtml

Question 6

What can be done to secure the virtual terminal interfaces on a router? (Choose two.)

  • A. Administratively shut down the interface.
  • B. Physically secure the interface.
  • C. Create an access list and apply it to the virtual terminal interfaces with the access-group command.
  • D. Configure a virtual terminal password and login process.
  • E. Enter an access list and apply it to the virtual terminal interfaces using the access-class command.


Answer : D,E

Explanation: It is a waste to administratively shut down the interface. Moreover, someone can still access the virtual terminal interfaces via other interfaces -> A is not correct. We can not physically secure a virtual interface because it is virtual -> B is not correct. To apply an access list to a virtual terminal interface we must use the access-class command. The access-group command is only used to apply an access list to a physical interface -> C is not correct; E is correct. The most simple way to secure the virtual terminal interface is to configure a username & password to prevent unauthorized login -> D is correct.

Question 7

Refer to the exhibit.


The network is converged. After link-state advertisements are received from Router_A,
what information will Router_E contain in its routing table for the subnets 208.149.23.64
and 208.149.23.96?

  • A. O 208.149.23.64 [110/13] via 190.173.23.10, 00:00:07, FastEthernet 0/0 O 208.149.23.96 [110/13] via 190.173.23.10, 00:00:16, FastEthernet 0/0
  • B. O 208.149.23.64 [110/1] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/3] via 190.173.23.10, 00:00:16, FastEthernet 0/0
  • C. O 208.149.23.64 [110/13] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/13] via 190.172.23.10, 00:00:16, Serial 1/0 O 208.149.23.96 [110/13] via 190.173.23.10, 00:00:16, FastEthernet 0/0
  • D. O 208.149.23.64 [110/3] via 190.172.23.10, 00:00:07, Serial 1/0 O 208.149.23.96 [110/3] via 190.172.23.10, 00:00:16, Serial 1/0


Answer : A

Explanation: Router_E learns two subnets subnets 208.149.23.64 and 208.149.23.96 via Router_A through FastEthernet interface. The interface cost is calculated with the formula 108 /Bandwidth. For FastEthernet it is 108 / 100 Mbps = 108 / 100,000,000 = 1. Therefore the cost is12(learned from Router_A)+ 1=13for both subnets - B is not correct. The cost through T1 link is much higher than through T3 link (T1 cost = 108 / 1.544 Mbps = 64; T3 cost = 108 / 45 Mbps = 2) so surely OSPF will choose the path through T3 link -> Router_E will choose the path from Router_A through FastEthernet0/0, not Serial1/0 - C & D are not correct. In fact, we can quickly eliminate answers B, C and D because they contain at least one subnet learned from Serial1/0 - they are surely incorrect.

Question 8

Refer to the exhibit.


Given the output from the show ip eigrp topology command, which router is the feasible
successor?
A)

B)

C)

D)

  • A. Exhibit A
  • B. Exhibit B
  • C. Exhibit C
  • D. Exhibit D


Answer : B

Explanation: http://networklessons.com/eigrp/eigrp-neighbor-and-topology-table-explained/ To be the feasible successor, the Advertised Distance (AD) of that route must be less than the Feasible Distance (FD) of the successor. From the output of the show ip eigrp topology 10.0.0.5 255.255.255.255 we learn that the FD of the successor is 41152000. Now we will mention about the answers, in the Composite metric is (/) statement the first parameter is the FD while the second parameter is the AD of that route. So we need to find out which route has the second parameter (AD) less than 41152000 -> only answer B satisfies this requirement with an AD of 128256.

Question 9

Refer to the exhibit.


Given the output for this command, if the router ID has not been manually set, what router
ID will OSPF use for this router?

  • A. 10.1.1.2
  • B. 10.154.154.1
  • C. 172.16.5.1
  • D. 192.168.5.3


Answer : C

Explanation: CCNA Tutorial: The OSPF Router ID (RID) http://www.thebryantadvantage.com/CCNACertificationExamTutorialOSPFRouterIDRID.ht m When determining the Router ID (RID) of an OSPF-enabled router, OSPF will always use the numerically highest IP address on the routers loopback interfaces, regardless of whether that loopback is OSPF-enabled. What if there is no loopback? OSPF will then use the numerically highest IP address of the physical interfaces, regardless of whether that interface is OSPF-enabled.

Question 10

Refer to Exhibit:


The internetwork infrastructure of company XYZ consists of a single OSPF area as shown
in the graphic. There is concern that a lack of router resources is impeding internetwork
performance. As part of examining the router resources, the OSPF DRs need to be known.
All the router OSPF priorities are at the default and the router IDs are shown with each
router. Which routers are likely to have been elected as DR? (Choose two.)

  • A. Corp-1
  • B. Corp-2
  • C. Corp-3
  • D. Corp-4
  • E. Branch-1
  • F. Branch-2


Answer : D,F

Explanation: There are 2 segments on the topology above which are separated by Corp-3 router. Each segment will have a DR so we have 2 DRs. To select which router will become DR they will compare their router-IDs. The router with highest (best) router-ID will become DR. The router-ID is chosen in the order below: The highest IP address assigned to a loopback (logical) interface. If a loopback interface is not defined, the highest IP address of all active routers physical interfaces will be chosen. In this question, the IP addresses of loopback interfaces are not mentioned so we will consider IP addresses of all active routers physical interfaces. Router Corp-4 (10.1.40.40) & Branch-2 (10.2.20.20) have highest active IP addresses so they will become DRs.

Question 11

What does a router do if it has no EIGRP feasible successor route to a destination network
and the successor route to that destination network is in active status?

  • A. It routes all traffic that is addressed to the destination network to the interface indicated in the routing table.
  • B. It sends a copy of its neighbor table to all adjacent routers.
  • C. It sends a multicast query packet to all adjacent neighbors requesting available routing paths to the destination network.
  • D. It broadcasts Hello packets to all routers in the network to re-establish neighbor adjacencies.


Answer : C

Explanation: Introduction to EIGRP Reference: http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080093f07.shtml Explanation: Feasible Successors A destination entry is moved from the topology table to the routing table when there is a feasible successor. All minimum cost paths to the destination form a set. From this set, the neighbors that have an advertised metric less than the current routing table metric are considered feasible successors. Feasible successors are viewed by a router as neighbors that are downstream with respect to the destination. These neighbors and the associated metrics are placed in the forwarding table. When a neighbor changes the metric it has been advertising or a topology change occurs in the network, the set of feasible successors may have to be re-evaluated. However, this is not categorized as a route recomputation. Route States A topology table entry for a destination can have one of two states. A route is considered in the Passive state when a router is not performing a route recomputation. The route is in Active state when a router is undergoing a route recomputation. If there are always feasible successors, a route never has to go into Active state and avoids a route recomputation. When there are no feasible successors, a route goes into Active state and a route recomputation occurs. A route recomputation commences with a router sending a query packet to all neighbors. Neighboring routers can either reply if they have feasible successors for the destination or optionally return a query indicating that they are performing a route recomputation. While in Active state, a router cannot change the next- hop neighbor it is using to forward packets. Once all replies are received for a given query, the destination can transition to Passive state and a new successor can be selected. When a link to a neighbor that is the only feasible successor goes down, all routes through that neighbor commence a route recomputation and ent

Question 12

Refer to the exhibit.


When running EIGRP, what is required for RouterA to exchange routing updates with
RouterC?

  • A. AS numbers must be changed to match on all the routers
  • B. Loopback interfaces must be configured so a DR is elected
  • C. The no auto-summary command is needed on Router A and Router C
  • D. Router B needs to have two network statements, one for each connected network


Answer : A

Explanation: Here we required same autonomous system between router A,B,C.Routing updated always exchange between in same EIGRP EIGRP autonomous system.you can configure more than one EIGRP autonomous system on the same router. This is typically done at a redistribution point where two EIGRP autonomous systems are interconnected. Individual router interfaces should only be included within a single EIGRP autonomous system. Cisco does not recommend running multiple EIGRP autonomous systems on the same set of interfaces on the router. If multiple EIGRP autonomous systems are used with multiple points of mutual redistribution, it can cause discrepancies in the EIGRP topology table if correct filtering is not performed at the redistribution points. If possible, Cisco recommends you configure only one EIGRP autonomous system in any single autonomous system. http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080093f07.shtml

Question 13

Which statement is true, as relates to classful or classless routing?

  • A. Classful routing protocols send the subnet mask in routing updates.
  • B. RIPv1 and OSPF are classless routing protocols.
  • C. Automatic summarization at classful boundaries can cause problems on discontiguous subnets.
  • D. EIGRP and OSPF are classful routing protocols and summarize routes by default.


Answer : C

Explanation: http://www.ciscopress.com/articles/article.asp?p=174107&seqNum=3 RIPv1, RIPv2, IGRP, and EIGRP all auto-summarize classful boundaries by default (OSPF does not).To make discontiguous networks work, meaning you don't want classful boundries to summarize, you need to turn off auto-summary.

Question 14

A router is running three routing processes: RIP, OSPF, and EIGRP, each configured with
default characteristics. Each process learns a route to the same remote network.
If there are no static routes to the destination and none of the routes were redistributed,
which route will be placed in the IP routing table?

  • A. the route learned through EIGRP
  • B. the route learned through OSPF
  • C. the route learned through RIP
  • D. the route with the lowest metric
  • E. all three routes with the router load balancing


Answer : A

Reference: http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094195.shtml Administrative distance is the feature that routers use in order to select the best path. Administrative distance defines the reliability of a routing protocol. Each routing protocol is prioritized in order of most to least reliable (believable) with the help of an administrative distance value. Lowest Administrative distance will be chosen first.

Question 15

What are two drawbacks of implementing a link-state routing protocol? (Choose two.)

  • A. the sequencing and acknowledgment of link-state packets
  • B. the requirement for a hierarchical IP addressing scheme for optimal functionality
  • C. the high volume of link-state advertisements in a converged network
  • D. the high demand on router resources to run the link-state routing algorithm
  • E. the large size of the topology table listing all advertised routes in the converged network


Answer : B,D

Explanation: Link State routing protocols, such as OSPF and IS-IS, converge more quickly than their distance vector routing protocols such as RIPv1, RIPv2, EIGRP and so on, through the use of flooding and triggered updates. In link state protocols, changes are flooded immediately and computed in parallel. Triggered updates improve convergence time by requiring routers to send an update message immediately upon learning of a route change. These updates are triggered by some event, such as a new link becoming available oor an existing link failing. The main drawbacks to link state routing protocols are the amount of CPU overhead involved in calculating route changes and memory resources that are required to store neighbor tables, route tables and a complete topology table. http://www.ciscopress.com/articles/article.asp?p=24090&seqNum=4

Page 1