Cisco 200-101 Online Practice Questions and Exam Preparation

Cisco 200-101 Online Questions & Answers

• Question 121:

  What command visualizes the general NetFlow data on the command line?

  A. show ip flow export
  B. show ip flow top-talkers
  C. show ip cache flow
  D. show mls sampling
  E. show mls netflow ip
  C. show ip cache flow

• Question 122:

  What are two characteristics of Frame Relay point-to-point subinterfaces? (Choose two.)

  A. They create split-horizon issues.
  B. They require a unique subnet within a routing domain.
  C. They emulate leased lines.
  D. They are ideal for full-mesh topologies.
  E. They require the use of NBMA options when using OSPF.
  B. They require a unique subnet within a routing domain.
  C. They emulate leased lines.

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  http://www.ciscopress.com/articles/article.asp?p=170741andseqNum=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.

• Question 123:

  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.
  A. Router R2 will not form a neighbor relationship with R1.

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  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).

• Question 124:

  

  After the network has converged, what type of messaging, if any, occurs between R3 and R4?

  A. No messages are exchanged.
  B. Hellos are sent every 10 seconds.
  C. The full database from each router is sent every 30 seconds.
  D. The routing table from each router is sent every 60 seconds.
  B. Hellos are sent every 10 seconds.

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  HELLO messages are used to maintain adjacent neighbors so even when the network is converged, hellos are still exchanged. On broadcast and point-to-point links, the default is 10 seconds, on NBMA the default is 30 seconds.

• Question 125:

  Refer to the exhibit.

  

  The following commands are executed on interface fa0/1 of 2950Switch.

  2950Switch(config-if)# switchport port-security 2950Switch(config-if)# switchport port-security mac-address sticky 2950Switch(config-if)# switchport port-security maximum 1 The Ethernet frame that is shown arrives on interface fa0/1. What two functions will occur when this frame is received by 2950Switch? (Choose two.)

  A. The MAC address table will now have an additional entry of fa0/1 FFFF.FFFF.FFFF.
  B. Only host A will be allowed to transmit frames on fa0/1.
  C. This frame will be discarded when it is received by 2950Switch.
  D. All frames arriving on 2950Switch with a destination of 0000.00aa.aaaa will be forwarded out fa0/1.
  E. Hosts B and C may forward frames out fa0/1 but frames arriving from other switches will not be forwarded out fa0/1.
  F. Only frames from source 0000.00bb.bbbb, the first learned MAC address of 2950Switch, will be forwarded out fa0/1.
  B. Only host A will be allowed to transmit frames on fa0/1.
  D. All frames arriving on 2950Switch with a destination of 0000.00aa.aaaa will be forwarded out fa0/1.

• Question 126:

  Select and Place:

  

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• Question 127:

  

  To allow or prevent load balancing to network 172.16.3.0/24, which of the following commands could be used in R2? (Choose two.)

  A. R2(config-if)#clock rate
  B. R2(config-if)#bandwidth
  C. R2(config-if)#ip ospf cost
  D. R2(config-if)#ip ospf priority
  E. R2(config-router)#distance ospf
  B. R2(config-if)#bandwidth
  C. R2(config-if)#ip ospf cost

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  OSPF Cost http://www.cisco.com/en/US/tech/tk365/technologies_white_paper09186a0080094e9e.shtml#t6 The cost (also called metric) of an interface in OSPF is an indication of the overhead required to send packets across a certain interface. The cost of an interface is inversely proportional to the bandwidth of that interface. A higher bandwidth indicates a lower cost. There is more overhead (higher cost) and time delays involved in crossing a 56k serial line than crossing a 10M ethernet line. The formula used to calculate the cost is: cost= 10000 0000/bandwith in bps For example, it will cost 10 EXP8/10 EXP7 = 10 to cross a 10M Ethernet line and will cost 10 EXP8/1544000 =64 to cross a T1 line. By default, the cost of an interface is calculated based on the bandwidth; you can force the cost of an interface with the ip ospf cost interface subconfiguration mode command.

• Question 128:

  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
  B. the value of the local DLCI
  D. the status of the PVC that is configured on the router

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  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#wp1029343

  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)

• Question 129:

  Refer to the exhibit.

  

  Each of these four switches has been configured with a hostname, as well as being configured to run RSTP. No other configuration changes have been made. Which three of these show the correct RSTP port roles for the indicated switches and interfaces? (Choose three.)

  A. SwitchA, Fa0/2, designated
  B. SwitchA, Fa0/1, root
  C. SwitchB, Gi0/2, root
  D. SwitchB, Gi0/1, designated
  E. SwitchC, Fa0/2, root
  F. SwitchD, Gi0/2, root
  A. SwitchA, Fa0/2, designated
  B. SwitchA, Fa0/1, root
  F. SwitchD, Gi0/2, root

  ---

  The question says "no other configuration changes have been made" so we can understand these switches have the same bridge priority. SwitchC has lowest MAC address so, it will become root bridge and 2 of its ports (Fa0/1 and Fa0/2) will be designated ports (DP). Because SwitchC is the root bridge the 2 ports nearest SwitchC on SwitchA (Fa0/1) and SwitchD (Gi0/2) will be root ports (RP) -> B and F are correct.

  SwitchB must have a root port so which port will it choose? To answer this question we need to know about STP cost and port cost. In general, "cost" is calculated based on bandwidth of the link. The higher the bandwidth on a link, the lower the value of its cost. Below are the cost values you should memorize: Link speed Cost SwitchB will choose the interface with lower cost to the root bridge as the root port so we must calculate the cost on interface Gi0/1 and Gi0/2 of SwitchB to the root bridge. This can be calculated from the "cost to the root bridge" of each switch because a switch always advertises its cost to the root bridge in its BPDU. The receiving switch will add its local port cost value to the cost in the BPDU. SwitchC advertises its cost to the root bridge with a value of 0. Switch D adds 4 (the cost value of 1Gbps link) and advertises this value (4) to SwitchB. SwitchB adds another 4 and learns that it can reach SwitchC via Gi0/1 port with a total cost of 8. The same process happens for SwitchA and SwitchB learns that it can reach SwitchC via Gi0/2 with a total cost of 23 -> Switch B chooses Gi0/1 as its root port. Now our last task is to identify the port roles of the ports between SwitchA and SwitchB. It is rather easy as the MAC address of SwitchA is lower than that of SwitchB so Fa0/2 of SwitchA will be designated port while Gi0/2 of SwitchB will be alternative port.

• Question 130:

  What are the benefit of using Netflow? (Choose three.)

  A. Network, Application and User Monitoring
  B. Network Planning
  C. Security Analysis
  D. Accounting/Billing
  A. Network, Application and User Monitoring
  C. Security Analysis
  D. Accounting/Billing

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  NetFlow Definitions and Benefits

  Reference:

  http://www.cisco.com/en/US/products/sw/netmgtsw/ps1964/products_implementation_design_guide0918 6a00800d6a11.html#wp1030045

  NetFlow traditionally enables several key customer applications including:

  Network Monitoring--NetFlow data enables extensive near real time network monitoring capabilities. Flowbased analysis techniques may be utilized to visualize traffic patterns associated with individual routers and switches as well as on a

  network-wide basis (providing aggregate traffic or application based views) to provide proactive problem detection, efficient troubleshooting, and rapid problem resolution.

  Application Monitoring and Profiling--NetFlow data enables network managers to gain a detailed, timebased, view of application usage over the network. This information is used to plan, understand new services, and allocate network and

  application resources (e.g. Web server sizing and VoIP deployment) to responsively meet customer demands. User Monitoring and Profiling--NetFlow data enables network engineers to gain detailed understanding of customer/user utilization

  of network and application resources. This information may then be utilized to efficiently plan and allocate access, backbone and application resources as well as to detect and resolve potential security and policy violations. Network

  Planning--NetFlow can be used to capture data over a long period of time producing the opportunity to track and anticipate network growth and plan upgrades to increase the number of routing devices, ports, or higher- bandwidth interfaces.

  NetFlow services data optimizes network planning including peering, backbone upgrade planning, and routing policy planning. NetFlow helps to minimize the total cost of network operations while maximizing network performance, capacity,

  and reliability. NetFlow detects unwanted WAN traffic, validates bandwidth and Quality of Service (QOS) and allows the analysis of new network applications. NetFlow will give you valuable information to reduce the cost of operating your

  network. Security Analysis--NetFlow identifies and classifies DDOS attacks, viruses and worms in real- time. Changes in network behavior indicate anomalies that are clearly demonstrated in NetFlow data. The data is also a valuable forensic

  tool to understand and replay the history of security incidents.

  Accounting/Billing--NetFlow data provides fine-grained metering (e.g. flow data includes details such as IP addresses, packet and byte counts, timestamps, type- of-service and application ports, etc.) for highly flexible and detailed resource

  utilization accounting. Service providers may utilize the information for billing based on time-of-day, bandwidth usage, application usage, quality of service, etc. Enterprise customers may utilize the information for departmental charge- back or

  cost allocation for resource utilization.

  NetFlow Data Warehousing and Data Mining--NetFlow data (or derived information) can be warehoused for later retrieval and analysis in support of proactive marketing and customer service programs (e.g. figure out which applications and

  services are being utilized by internal and external users and target them for improved service, advertising, etc.). In addition, NetFlow data gives Market Researchers access to the "who", "what", "where", and "how long" information relevant to

  enterprises and service providers.