1.
1. Which three actions might a Frame Relay switch perform when it detects an excessive build-up of frames in its queue? (Choose three.)
Correct Answer(s)
B. Drops frames from the queue that have the DE bit set
E. Sets the FECN bit on all frames it receives on the congested link
F. Sets the BECN bit on all frames it places on the congested link
Explanation
When a Frame Relay switch detects an excessive build-up of frames in its queue, it performs three actions. Firstly, it drops frames from the queue that have the DE (Discard Eligible) bit set. Secondly, it sets the FECN (Forward Explicit Congestion Notification) bit on all frames it receives on the congested link, indicating to the receiving device that congestion is occurring. Lastly, it sets the BECN (Backward Explicit Congestion Notification) bit on all frames it places on the congested link, informing the sending device about the congestion. These actions help manage and alleviate congestion in the Frame Relay network.
2.
2. Which best describes the benefit of using Frame Relay as opposed to a leased line or ISDN service?
Correct Answer
C. Customers only pay for the local loop and the bandwidth they purchase from the network provider.
Explanation
The benefit of using Frame Relay as opposed to a leased line or ISDN service is that customers only pay for the local loop and the bandwidth they purchase from the network provider. Unlike leased lines or ISDN services where customers pay for an end-to-end connection that includes the local loop and the network link, with Frame Relay, customers have the flexibility to choose and pay for only the local loop and the specific bandwidth they require from the network provider. This allows for more cost-effective and customizable network solutions for customers.
3.
Refer to the exhibit. Router R1 has been configured for Frame Relay connectivity to routers R2 and R3. What configuration option should be configured on the R2 and R3 serial interfaces in order for all routers to ping each other successfully?
Correct Answer
D. R2(config-if)# frame-relay map ip 10.1.1.1 201 broadcast
R2(config-if)# frame-relay map ip 10.1.1.3 201 broadcast
R3(config-if)# frame-relay map ip 10.1.1.1 301 broadcast
R3(config-if)# frame-relay map ip 10.1.1.2 301 broadcast
Explanation
The correct answer is the configuration option that includes the correct IP addresses and DLCIs for each router. In this case, R2 should have a frame-relay map command for IP address 10.1.1.1 with DLCI 201, and IP address 10.1.1.3 with DLCI 201. R3 should have a frame-relay map command for IP address 10.1.1.1 with DLCI 301, and IP address 10.1.1.2 with DLCI 301. This configuration allows for successful pinging between all routers.
4.
4. Which two items allow the router to map data link layer addresses to network layer addresses in a Frame Relay network? (Choose two.)
Correct Answer(s)
D. Inverse ARP
E. LMI status messages
Explanation
Inverse ARP and LMI status messages are the two items that allow the router to map data link layer addresses to network layer addresses in a Frame Relay network. Inverse ARP is used to dynamically map the network layer (IP) addresses to the data link layer (MAC) addresses in Frame Relay. LMI (Local Management Interface) status messages are used to exchange information between the router and the Frame Relay switch, including mapping tables that associate data link layer addresses with network layer addresses.
5.
Refer to the exhibit. Which two outcomes occur from the configuration shown? (Choose two.)
Correct Answer(s)
B. The router will use DLCI 22 to forward data to 10.1.1.1.
E. Frames sent by 10.1.1.1 arriving on interface serial 0/0/0 of RT_1 will have a data link layer address of 22.
Explanation
The configuration shown indicates that DLCI 22 is being used for forwarding data to the IP address 10.1.1.1. This means that the router will use DLCI 22 to send data packets to the destination IP address. Additionally, frames sent by 10.1.1.1 and arriving on interface serial 0/0/0 of RT_1 will have a data link layer address of 22. This suggests that the frames will be encapsulated with DLCI 22 as the data link layer address during transmission.
6.
Refer to the exhibit. What can be determined about the Frame Relay switch from the output shown?
Correct Answer
D. It is experiencing congestion.
Explanation
The output shows that the Frame Relay switch has a high number of frames in BECN (Backward Explicit Congestion Notification) and FECN (Forward Explicit Congestion Notification) states. This indicates that the switch is experiencing congestion and is unable to process frames at the desired rate.
7.
Refer to the exhibit. What can be determined from the output?
Correct Answer
B. Serial 0/0/0 has the feature frame-relay inverse-arp enabled
Explanation
The output shows that Serial 0/0/0 has the feature frame-relay inverse-arp enabled. This means that the router is using Inverse ARP (Address Resolution Protocol) to dynamically map IP addresses to DLCIs (Data Link Connection Identifiers) in a frame-relay network. Inverse ARP allows the router to automatically discover the DLCI associated with a particular IP address, simplifying the configuration process.
8.
Refer to the exhibit. What effect does the point-to-point configuration on subinterface S0/0.110 have on the operation of the router?
Correct Answer
C. It eliminates split horizon issues without increasing the likelihood of routing loops.
Explanation
The point-to-point configuration on subinterface S0/0.110 eliminates split horizon issues without increasing the likelihood of routing loops. Split horizon is a technique used in routing protocols to prevent routing loops by not advertising a route back out of the interface it was learned from. In a point-to-point configuration, there is only one possible path between two devices, so split horizon is not necessary. By eliminating split horizon, the router can advertise routes more efficiently and prevent unnecessary routing loops. The other options are incorrect because they do not relate to the effect of the point-to-point configuration on the router's operation.
9.
Refer to the exhibit. Which statement explains why the Frame Relay connection between R1 and R2 is failing?
Correct Answer
D. The frame-relay map commands are using incorrect DLCIs.
Explanation
The Frame Relay connection between R1 and R2 is failing because the frame-relay map commands are using incorrect DLCIs. This means that the Data Link Connection Identifiers (DLCIs) specified in the frame-relay map commands do not match the DLCIs assigned by the service provider. As a result, the routers are unable to establish a successful connection over the Frame Relay network.
10.
10. What best describes the use of a data-link connection identifier (DLCI)?
Correct Answer
B. Locally significant address used to identify a virtual circuit
Explanation
A data-link connection identifier (DLCI) is a locally significant address that is used to identify a virtual circuit. This means that the DLCI serves as a label or identifier for a specific connection within a Frame Relay network. It helps to differentiate and establish a connection between different virtual circuits within the network. The DLCI is used to route data packets to the correct destination across the network.
11.
Refer to the exhibit. Router R1 has been configured for Frame Relay connectivity to routers R2 and R3. Which set of configuration options for routers R2 and R3 would provide each router connectivity to R1?
Correct Answer
D. R2(config)# interface serial0/0/1.201 point-to-point
R2(config-if)# frame-relay interface-dlci 201
R3(config)# interface serial0/0/1.301 point-to-point
R3(config-if)# frame-relay interface-dlci 301
Explanation
The correct answer is the last set of configuration options. In this configuration, R2 is configured with a point-to-point interface on serial0/0/1.201 and R3 is configured with a point-to-point interface on serial0/0/1.301. The frame-relay interface-dlci command is used to specify the Data Link Connection Identifier (DLCI) for each interface, with R2 using DLCI 201 and R3 using DLCI 301. This configuration allows each router to establish a direct point-to-point connection with R1, providing connectivity between all three routers.
12.
Refer to the exhibit. Frame Relay connectivity has been configured in the network and OSPF is used as the routing protocol. Router R1 can successfully ping the router R2 serial interface. When R1 attempts to ping network 192.168.3.0/24 the ping fails. What additional configuration should be applied on all routers to remedy the problem?
Correct Answer
A. Add the broadcast keyword in the Frame Relay map command on both routers.
Explanation
Adding the broadcast keyword in the Frame Relay map command on both routers will allow the routers to forward broadcast traffic over the Frame Relay network. By default, Frame Relay does not forward broadcast traffic, so adding the broadcast keyword will enable the routers to send and receive broadcast packets. This will allow router R1 to successfully ping network 192.168.3.0/24.
13.
13. Which statement about Frame Relay subinterfaces is correct?
Correct Answer
B. Point-to-point subinterfaces act like leased lines and eliminate split-horizon routing issues.
Explanation
Point-to-point subinterfaces act like leased lines and eliminate split-horizon routing issues. This means that each subinterface is treated as a separate connection, allowing for direct communication between the two endpoints without any routing restrictions. This eliminates the need for split-horizon routing, which prevents routing loops in networks with redundant connections. By using point-to-point subinterfaces, the Frame Relay network can efficiently transmit data without the risk of routing issues.
14.
Refer to the exhibit. What can be determined about the configuration of router R1 from the exhibited output?
Correct Answer
B. The LMI type for the Serial 0/0/0 interface has been left to its default configuration.
Explanation
The correct answer suggests that the LMI type for the Serial 0/0/0 interface has not been modified and is still in its default configuration. This means that the router is using the default LMI type for that interface, which could indicate that LMI updates are being received properly. However, the other options do not provide any information about the LMI updates or the configuration of the interface.
15.
15. What is created between two DTEs in a Frame Relay network?
Correct Answer
D. Virtual circuit
Explanation
In a Frame Relay network, a virtual circuit is created between two DTEs (Data Terminal Equipment). A virtual circuit is a logical connection that allows data to be transmitted between the two devices. It provides a communication path that appears to be a dedicated physical circuit, even though it is actually sharing the physical network infrastructure with other virtual circuits. This allows for efficient and cost-effective data transmission in a Frame Relay network.
16.
16. Which Frame Relay topology is a compromise of costs, reliability, and complexity when the WAN contains one headquarters site, 40 regional sites, and several sites within each regional site?
Correct Answer
C. Partial mesh
Explanation
A partial mesh topology is a compromise of costs, reliability, and complexity when the WAN contains one headquarters site, 40 regional sites, and several sites within each regional site. In a partial mesh topology, not all sites are directly connected to each other, but there are still multiple connections between different sites. This allows for efficient communication between the headquarters and regional sites, as well as between the sites within each region. It strikes a balance between the high cost and complexity of a full mesh topology and the limited connectivity of a star or point-to-point topology.
17.
Refer to the exhibit. A ping is sent to address 192.168.50.10 from the Peanut router. Which DLCI will be used to send the ping?
Correct Answer
A. 110
Explanation
Based on the information given in the exhibit, the DLCI 110 will be used to send the ping.
18.
18. What two methods does Frame Relay technology use to process frames that contain errors? (Choose two.)
Correct Answer(s)
A. Frame Relay services depend on the upper layer protocols to handle error recovery.
D. The receiving device drops any frames that contain errors without notifying the sender.
Explanation
Frame Relay technology uses two methods to process frames that contain errors. Firstly, it depends on the upper layer protocols to handle error recovery. This means that the higher layer protocols, such as TCP/IP, are responsible for detecting and recovering from errors. Secondly, the receiving device drops any frames that contain errors without notifying the sender. This means that if a frame is found to have errors, it is simply discarded by the receiving device without any notification sent back to the sender. These two methods help to ensure efficient and reliable transmission of data over Frame Relay networks.
19.
Refer to the exhibit. Which two statements are true given the output shown? (Choose two.)
Correct Answer(s)
B. The local DLCI number is 401.
C. Inverse ARP is being used on this connection.
Explanation
The correct answer is that the local DLCI number is 401 and Inverse ARP is being used on this connection. This can be determined from the output shown in the exhibit. The line "Local DLCI 401" indicates that the local DLCI number is indeed 401. Additionally, the line "Type: dynamic, Status: active" suggests that Inverse ARP is being used, as Inverse ARP dynamically maps IP addresses to DLCI numbers.
20.
Refer to the exhibit. What can be known about the configuration of router R1 from the output?
Correct Answer
D. The command encapsulation frame-relay ietf has been used on the Serial 0/0/0 interface.
Explanation
The output indicates that the command "encapsulation frame-relay ietf" has been used on the Serial 0/0/0 interface of router R1.
21.
21. What consideration must be taken into account if RIP is used on Frame Relay multiaccess networks?
Correct Answer
A. To forward routing updates, address-to-DLCI mapping must be done via the use of the frame-relay map command coupled with the broadcast keyword.
Explanation
In order to forward routing updates on Frame Relay multiaccess networks, the address-to-DLCI mapping must be established using the frame-relay map command along with the broadcast keyword. This allows the routing updates to be sent as broadcast traffic to all connected nodes on the network. By using this mapping, the updates can be properly propagated and reach their intended destinations.
22.
Refer to the exhibit. You are a network administrator who has been tasked with completing the Frame Relay topology that interconnects two remote sites. Router HQ belongs to both the 172.16.1.0/24 and 172.16.2.0/24 subnets with IP addresses of 172.16.1.3 and 172.16.2.3 respectively. Traffic between R1 and R2 must travel through HQ first. How should the serial interface on HQ be configured to complete the topology?
Correct Answer
B. Two point-to-point subinterfaces
Explanation
To complete the Frame Relay topology and allow traffic between R1 and R2 to travel through HQ first, the serial interface on HQ should be configured with two point-to-point subinterfaces. This configuration will enable separate virtual circuits to be established between HQ and each of the remote sites. Each subinterface will have its own IP address, allowing for proper routing and communication between the sites.