Cisco 200-105 Free Practice Questions

Answer: A,D,E 

Explanation: 

http://www.cisco.com/en/US/docs/ios/12_2/wan/command/reference/wrffr4.html#wp102934 

Answer: A,B,D 

Explanation: 

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cf 

a.shtml 

Convergence 

Cisco enhanced the original 802.1D specification with features such as Uplink Fast, 

Backbone Fast, and Port Fast to speed up the convergence time of a bridged network. The 

drawback is that these mechanisms are proprietary and need additional configuration. 

Alternate and Backup Port Roles 

These two port roles correspond to the blocking state of 802.1D. A blocked port is defined 

as not being the designated or root port. A blocked port receives a more useful BPDU than 

the one it sends out on its segment. 

Remember that a port absolutely needs to receive BPDUs in order to stay blocked. RSTP 

introduces these two roles for this purpose. 

Rapid Transition to Forwarding State 

Rapid transition is the most important feature introduced by 802.1w. The legacy STA 

passively waited for the network to converge before it turned a port into the forwarding 

state. The achievement of faster convergence was a matter of tuning the conservative 

default parameters (forward delay and max_age timers) and often put the stability of the 

network at stake. The new rapid STP is able to actively confirm that a port can safely 

transition to the forwarding state without having to rely on any timer configuration. There is 

now a real feedback mechanism that takes place between RSTP-compliant bridges. In order to achieve fast convergence on a port, the protocol relies upon two new variables: edge ports and link type. 

Answer: B 

Explanation: The Process ID for OSPF on a router is only locally significant and you can use the same number on each router, or each router can have a different number-it just doesn't matter. The numbers you can use are from 1 to 65,535. Don't get this confused with area numbers, which can be from 0 to 4.2 billion. 

Answer:  

Explanation: 

+ holddown timer: prevents a router from improperly reinstating a route from a regular routing update 

+ split horizon: prevents information about a route from being sent in the direction from which the route was learned 

+ defining a maximum: prevents invalid updates from looping the internetwork indefinitely 

+ route poisoning: causes a routing protocol to advertise an infinite metric for a failed route 

+ triggered update: decreases convergence time by immediately sending route information in response to a topology change 

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. 

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 router’s 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. 

Answer: C 

Explanation: 

Cisco Frame Relay Configurations http://www.ciscopress.com/articles/article.asp?p=170741&seqNum=9 show frame-relay map The show frame-relay map privileged EXEC mode command shows the contents of the next hop protocol address to DLCI mapping table on the router. The table contains both dynamic mapped and static mapped entries. The below example shows a sample output of the show frame-relay map command. Router#show frame-relay map Serial1/2 (up): ip 172.16.1.4 dlci 401(0x191,0x6410), dynamic, broadcast,, status defined, active Serial1/2 (up): ip 172.16.1.5 dlci 501(0x1F5,0x7C50), dynamic, broadcast,, status defined, active Serial1/2 (up): ip 172.16.1.2 dlci 301(0x12D,0x48D0), dynamic, broadcast,, status defined, active 

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. 

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. 

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 is 12 (learned from Router_A) + 1 = 13 for 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. 

Answer: C,E,F 

Explanation: 

EIGRP performs an auto-summarization each time it crosses a border between two different major networks, so when R2 advertises the routes to R4 it will advertise only the summarized routes of 10.0.0.0/8 and 172.16.0.0/16, along with the 192.168.1.0/24 route coming from R3. 

Answer: A,D 

Explanation: 

From the output of the “show ip ospf database”: r120#show ip ospf data 

OSPF Router with ID (10.0.0.120) (Process ID 1) 

Next, who are the other routers in our area? Router Link States (Area 1) Link ID.ADV Router.Age.Seq#.Checksum Link count 

10.0.0.111.10.0.0.111.600.0x8000023A 0x0092B3 1 

10.0.0.112.10.0.0.112.1246.0x80000234 0x009CAC 1 

10.0.0.113.10.0.0.113.148.0x8000022C 0x004399 3 

10.0.0.120.10.0.0.120.152.0x80000240 0x0046CB 1 This tells us there are four routers in Area 1. The router with RID 10.0.0.113 has 3 links in Area 1, every one else has only 1 link. Also the router will chose the highest loopback interface as its OSPF router ID (if available). 

Answer: A,D,E 

Explanation: Cisco VPN solutions provide exceptional security through encryption and authentication technologies that protect data in transit from unauthorized access and attacks. A Cisco VPN helps you: Use highly secure communications, with access rights tailored to individual users Quickly add new sites or users, without significantly expanding your existing infrastructure Improve productivity by extending corporate networks, applications, and collaboration tools Reduce communications costs while increasing flexibility 

Answer: B,C 

Explanation: http://www.ciscopress.com/articles/article.asp?p=170741&seqNum=5 

Configuring Frame Relay Subinterfaces On partially meshed Frame Relay networks, the problem of split horizon can be overcome by using Frame Relay subinterfaces. Frame Relay provides a mechanism to allow a physical interface to be partitioned into multiple virtual interfaces. In a similar way, using subinterfaces allows a partially meshed network to be divided into a number of smaller, fully meshed point-to-point networks. Generally, each point-to-point subnetwork is assigned a unique network address. This allows packets received on one physical interface to be sent out from the same physical interface, albeit forwarded on VCs in different subinterfaces. There are two types of subinterfaces supported by Cisco routers: point-to-point and multipoint subinterfaces. 

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 doesn’t 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 

Answer: C 

Explanation: 

"Show interface pos8/0/0" command showing LMI enq sent which show frame-relay encapsulation enabled on this interface. Cisco supports three different Local Management Interface (LMI) types for Frame Relay: Cisco, ANSI Annex D, and Q933-A Annex A http://www.ciscopress.com/articles/article.asp?p=170741&seqNum=3