Actualtests offers free demo for cisco 200 105 exam. "Interconnecting Cisco Networking Devices Part 2 (ICND2 v3.0)", also known as 105 200 exam, is a Cisco Certification. This set of posts, Passing the Cisco ccna routing and switching icnd2 200 105 official cert guide exam, will help you answer those questions. The icnd2 200 105 Questions & Answers covers all the knowledge points of the real exam. 100% real Cisco ccna routing and switching icnd2 200 105 official cert guide exams and revised by experts!
Q17. - (Topic 2)
Refer to the exhibit.
If the router Cisco returns the given output and has not had its router ID set manually, what value will OSPF use as its router ID?
A. 192.168.1.1
B. 172.16.1.1
C. 1.1.1.1
D. 2.2.2.2
Answer: D
Explanation:
If a router-id is not configured manually in the OSPF routing process the router will automatically configure a router-id determined from the highest IP address of a logical interface (loopback interface) or the highest IP address of an active interface. If more than one loopback interfaces are configured, the router will compare the IP addresses of each of the interfaces and choose the highest IP address from the loopbacks.
Q18. - (Topic 2)
Which parameter would you tune to affect the selection of a static route as a backup, when a dynamic protocol is also being used?
A. hop count
B. administrative distance
C. link bandwidth
D. link delay
E. link cost
Answer: B
Explanation:
What Is Administrative Distance?
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.
Q19. - (Topic 3)
Which two statements about using the CHAP authentication mechanism in a PPP link are true? (Choose two.)
A. CHAP uses a two-way handshake.
B. CHAP uses a three-way handshake.
C. CHAP authentication periodically occurs after link establishment.
D. CHAP authentication passwords are sent in plaintext.
E. CHAP authentication is performed only upon link establishment.
F. CHAP has no protection from playback attacks.
Answer: B,C
Explanation:
Understanding and Configuring PPP CHAP Authentication http://www.cisco.com/en/US/tech/tk713/tk507/technologies_tech_note09186a00800b4131. shtml
One-Way and Two-Way Authentication CHAP is defined as a one-way authentication method. However, you use CHAP in both directions to create a two-way authentication. Hence, with two-way CHAP, a separate three-way handshake is initiated by each side. In the Cisco CHAP implementation, by default, the called party must authenticate the calling party (unless authentication is completely turned off). Therefore, a one-way authentication initiated by the called party is the minimum possible authentication. However, the calling party can also verify the identity of the called party, and this results in a two-way authentication. One-way authentication is often required when you connect to non-Cisco devices.
Q20. - (Topic 2)
Refer to the exhibit.
How will the router handle a packet destined for 192.0.2.156?
A. The router will drop the packet.
B. The router will return the packet to its source.
C. The router will forward the packet via Serial2.
D. The router will forward the packet via either Serial0 or Serial1.
Answer: C
Explanation:
Router has pointed default router to 192.168.4.1 and this subnet is connected via serial 2 interface. Router does not have router for the 192.0.2.156. so it will use the default gateway
192.168.4.1. A default route identifies the gateway IP address to which the router sends all IP packets for which it does not have a learned or static route.
Q21. - (Topic 1)
What is one benefit of PVST+?
A. PVST+ supports Layer 3 load balancing without loops.
B. PVST+ reduces the CPU cycles for all the switches in the network.
C. PVST+ allows the root switch location to be optimized per VLAN.
D. PVST+ automatically selects the root bridge location, to provide optimized bandwidth usage.
Answer: C
Explanation:
Per VLAN Spanning Tree (PVST) Introduction http://www.cisco.com/en/US/tech/tk389/tk621/tk846/tsd_technology_support_sub-protocol_home.html Per VLAN Spanning Tree (PVST) maintains a spanning tree instance for each VLAN configured in the network. This means a switch can be the root bridge of a VLAN while another switch can be the root bridge of other VLANs in a common topology. For example, Switch 1 can be the root bridge for Voice data while Switch 2 can be the root bridge for Video data. If designed correctly, it can optimize the network traffic. http://www.ciscopress.com/articles/article.asp?p=102157&seqNum=4
Topic 2, Routing Technologies
Q22. - (Topic 1)
Which two states are the port states when RSTP has converged? (Choose two.)
A. discarding
B. listening
C. learning
D. forwarding
E. disabled
Answer: A,D
Explanation:
Understanding Rapid Spanning Tree Protocol (802.1w)
http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cf a.shtml
Port States There are only three port states left in RSTP that correspond to the three possible operational states. The 802.1D disabled, blocking, and listening states are merged into a unique 802.1w discarding state. RSTP only has 3 port states which are discarding, learning and forwarding. When RSTP has converged there are only 2 port states left: discarding and forwarding.
Q23. - (Topic 2)
What are two enhancements that OSPFv3 supports over OSPFv2? (Choose two.)
A. It requires the use of ARP.
B. It can support multiple IPv6 subnets on a single link.
C. It supports up to 2 instances of OSPFv3 over a common link.
D. It routes over links rather than over networks.
Answer: B,D Explanation:
Here is a list of the differences between OSPFv2 and OSPFv3:
They use different address families (OSPFv2 is for IPv4-only, OSPFv3 can be used for IPv6-only or both protocols OSPFv3 introduces new LSA types OSPFv3 has different packet format OSPFv3 uses different flooding scope bits (U/S2/S1) OSPFv3 adjacencies are formed over link-local IPv6 communications OSPFv3 runs per-link rather than per-subnet OSPFv3 supports multiple instances on a single link, Interfaces can have multiple IPv6 addresses OSPFv3 uses multicast addresses FF02::5 (all OSPF routers), FF02::6 (all OSPF DRs) OSPFv3 Neighbor Authentication done with IPsec (AH) OSPFv2 Router ID (RID) must be manually configured, still a 32-bit number
Reference: http://www.networkworld.com/article/2225270/cisco-subnet/ospfv3-for-ipv4-and-ipv6.html
Q24. - (Topic 2)
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 router’s 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 router’s 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.
Q25. - (Topic 1)
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
Q26. - (Topic 3)
What can be done to Frame Relay to resolve split-horizon issues?(Choose two.)
A. Disable Inverse ARP.
B. Create a full-mesh topology.
C. Develop multipoint subinterfaces.
D. Configure point-to-point subinterfaces.
E. Remove the broadcast keyword from the frame-relay map command.
Answer: B,D
Explanation:
IP split horizon checking is disabled by default for Frame Relay encapsulation to allow routing updates to go in and out of the same interface. An exception is the Enhanced Interior Gateway Routing Protocol (EIGRP) for which split horizon must be explicitly disabled. Certain protocols such as AppleTalk, transparent bridging, and Internetwork Packet Exchange (IPX) cannot be supported on partially meshed networks because they require split horizon to be enabled (a packet received on an interface cannot be transmitted over the same interface, even if the packet is received and transmitted on different virtual circuits). Configuring Frame Relay subinterfaces ensures that a single physical interface is treated as multiple virtual interfaces. This capability allows you to overcome split horizon rules so packets received on one virtual interface can be forwarded to another virtual interface, even if they are configured on the same physical interface.
Q27. - (Topic 3)
Which two statistics appear in show frame-relay map output? (Choose two.)
A. the number of BECN packets that are received by the router
B. the value of the local DLCI
C. the number of FECN packets that are received by the router
D. the status of the PVC that is configured on the router
E. the IP address of the local router
Answer: B,D
Explanation:
Frame Relay Commands (map-class frame-relay through threshold ecn)
http://www.cisco.com/en/US/docs/ios/12_2/wan/command/reference/wrffr4.html#wp102934
Examples
The following is sample output from the show frame-relay map command:
Router#show frame-relay map Serial 1 (administratively down): ip 10.108.177.177
dlci 177 (0xB1,0x2C10), static, broadcast,
CISCO
TCP/IP Header Compression (inherited), passive (inherited)
Q28. - (Topic 2)
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
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 enter the Active state.
Q29. - (Topic 3)
It has become necessary to configure an existing serial interface to accept a second Frame Relay virtual circuit. Which of the following are required to solve this? (Choose three)
A. configure static frame relay map entries for each subinterface network.
B. remove the ip address from the physical interface
C. create the virtual interfaces with the interface command
D. configure each subinterface with its own IP address
E. disable split horizon to prevent routing loops between the subinterface networks
F. encapsulate the physical interface with multipoint PPP
Answer: B,C,D
Explanation:
How To Configure Frame Relay Subinterfaces http://www.orbit-computer-solutions.com/How-To-Configure-Frame-Relay-Subinterfaces.php
Step to configure Frame Relay subinterfaces on a physical interface:
1. Remove any network layer address (IP) assigned to the physical interface. If the physical interface has an address, frames are not received by the local subinterfaces.
2. Configure Frame Relay encapsulation on the physical interface using the encapsulation frame-relay command.
3. For each of the defined PVCs, create a logical subinterface. Specify the port number, followed by a period (.) and the subinterface number. To make troubleshooting easier, it is suggested that the subinterface number matches the DLCI number.
4. Configure an IP address for the interface and set the bandwidth.
5. Configure the local DLCI on the subinterface using the frame-relay interface-dlci command. Configuration Example: R1>enable R1#configure terminal R1(config)#interface serial 0/0/0 R1(config-if)#no ip address R1(config-if)#encapsulation frame-relay R1(config-if)#no shutdown R1(config-if)#exit R1(config-subif)#interface serial 0/0/0.102 point-to-point R1(config-subif)#ip address 192.168.1.245 255.255.255.252 R1(config-subif)#frame-relay interface-dlci 102 R1(config-subif)#end R1#copy running-config startup-config
Q30. - (Topic 1)
Which two of these statements regarding RSTP are correct? (Choose two.)
A. RSTP cannot operate with PVST+.
B. RSTP defines new port roles.
C. RSTP defines no new port states.
D. RSTP is a proprietary implementation of IEEE 802.1D STP.
E. RSTP is compatible with the original IEEE 802.1D STP.
Answer: B,E
Explanation:
http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cf a.shtml
Port Roles The role is now a variable assigned to a given port. The root port and designated port roles remain, while the blocking port role is split into the backup and alternate port roles. The Spanning Tree Algorithm (STA) determines the role of a port based on Bridge Protocol Data Units (BPDUs). In order to simplify matters, the thing to remember about a BPDU is there is always a method to compare any two of them and decide whether one is more useful than the other. This is based on the value stored in the BPDU and occasionally on the port on which they are received. This considered, the information in this section explains practical approaches to port roles.
Compatibility with 802.1D RSTP is able to interoperate with legacy STP protocols. However, it is important to note that the inherent fast convergence benefits of 802.1w are lost when it interacts with legacy bridges.
Q31. - (Topic 2)
Refer to the exhibit.
Assume that all of the router interfaces are operational and configured correctly. How will router R2 be affected by the configuration of R1 that is shown in the exhibit?
A. Router R2 will not form a neighbor relationship with R1.
B. Router R2 will obtain a full routing table, including a default route, from R1.
C. R2 will obtain OSPF updates from R1, but will not obtain a default route from R1.
D. R2 will not have a route for the directly connected serial network, but all other directly connected networks will be present, as well as the two Ethernet networks connected to R1.
Answer: A
Explanation:
Open Shortest Path First http://en.wikipedia.org/wiki/Open_Shortest_Path_First
The configuration of R1 shows "router ospf 1" however, the diagram also shows that both routers should be in the backbone OSPF Area of "0". When routers are in different OSPF areas they will not form a neighbor relationship. Neighbor relationships As a link state routing protocol, OSPF establishes and maintains neighbor relationships in order to exchange routing updates with other routers. The neighbor relationship table is called an adjacency database in OSPF. Provided that OSPF is configured correctly, OSPF forms neighbor relationships only with the routers directly connected to it. In order to form a neighbor relationship between two routers, the interfaces used to form the relationship must be in the same area. Generally an interface is only configured in a single area, however you can configure an interface to belong to multiple areas. In the second area, such an interface must be configured as a secondary interface. (A neighbor state simulation shows how neighbor state changes from Down to Full Adjacency progressively with exchanging Hello, DD, Request, Update, and Ack packets).
Q32. - (Topic 2)
Refer to the exhibit.
The company uses EIGRP as the routing protocol. What path will packets take from a host on 192.168.10.192/26 network to a host on the LAN attached to router R1?
R3# show ip route Gateway of last resort is not set 192 168.20.0/24 is variably subnetted, 6 subnets, 2 masks D 192.168.20.64/26 [90/2195456] via 192.168.20.9, 00:03:31, Serial0/0 D 192.168.20.0/30 [90/2681856] via 192.168.20.9, 00:03:31, Serial0/0 C 192.168.20.4/30 is directly connected, Serial0/1 C 192.168.20.8/30 is directly connected, Serial0/0
C 192.168.20.192/26 is directly connected, FastEthernet0/0
D 192.168.20.128/26 [90/2195456] via 192.168.20.5,00:03:31, Serial0/1
A. The path of the packets will be R3 to R2 to R1
B. The path of the packets will be R3 to R1 to R2
C. The path of the packets will be both R3 to R2 to R1 and R3 to R1
D. The path of the packets will be R3 to R1
Answer: D
Explanation:
http://www.orbitco-ccna-pastquestions.com/CCNA---EIGRP-Common-Question.php
Looking at the output display above, the LAN attached to router R1 belongs to 192.168.20.64/26 subnet and learned this network via 192.168.20.9 which will be an IP address in 192.168.20.8/30 sub-network. This means that packets destined for
192.168.20.64 will be routed from R3 to R1.