CCNA3 - Lab 6.2.4 Part A: Configuring and Verifying Point-to-Point OSPF

Step 1: Connect the equipment

1. Connect the Fa0/0 interface of each router to the Fa0/1 interface of each switch using a straightthrough cable.
2. Connect each host to the Fa0/2 switch port of each switch using a straight-through cable.
3. Connect serial cables from each router to the other router as shown in the topology.

Step 2: Perform basic configurations on the routers

1. Connect a PC to the console port of the router to perform configurations using a terminal emulation program.
2. On all routers, configure the hostname, passwords, and message-of-the-day banner and disable DNS lookups according to the addressing table and topology diagram.

Step 3: Configure the router interfaces

Step 4: Verify IP addressing and interfaces

1. Use the show ip interface brief or the show protocols command to verify that the IP addressing is correct and that the interfaces are active.
2. After all interfaces are verified, be sure to save the running configuration to the NVRAM of the router.

Step 5: Configure Ethernet interfaces of PC1, PC2, and PC3

1. Configure the Ethernet interfaces of PC1, PC2, and PC3 with the IP addresses and default gateways from the addressing table.
2. Test the PC configuration by pinging the default gateway from each PC.

Step 6: Configure OSPF on Router 1

1. Configure OSPF on the R1 router. Enter a process ID of 1 for the process-ID parameter. R1(config)#router ospf 1
2. Configure the network statement for the LAN. When you are in the Router OSPF configuration submode, configure the LAN 172.16.1.16/28 to be included in the OSPF updates that are sent out of R1. Use an area ID of 0 for the OSPF area-id parameter. Zero will be used for the OSPF area ID in all network statements in this topology.

R1(config-router)#network 172.16.1.16 0.0.0.15 area 0

1. Configure the router to advertise the 192.168.10.0/30 network attached to the Serial 0/0/0 interface.

R1(config-router)#network 192.168.10.0 0.0.0.3 area 0

1. Configure the router to advertise the 192.168.10.4/30 network attached to the Serial 0/0/1 interface. R1(config-router)#network 192.168.10.4 0.0.0.3 area 0
2. Return to privileged EXEC mode and save the configuration.

Step 7: Configure OSPF on the R2 router

1. Enable OSPF routing on the R2 router using the router ospf command. Use a process ID of 1.

R2(config)#router ospf 1

1. Configure the router to advertise the LAN network 10.10.10.0/24 in the OSPF updates.

R2(config-router)#network 10.10.10.0 0.0.0.255 area 0

Step 8: Configure OSPF on the R3 router

Configure OSPF on the R3 router using the router ospf and network commands. Use a process ID of 1. Configure the router to advertise the three directly connected networks. When you are finished, return to privileged EXEC mode.

Step 9: Configure OSPF router IDs

1. The OSPF router ID is used to uniquely identify the router in the OSPF routing domain. A router ID is an IP address. Cisco routers derive the router ID in one of three ways, and with the following precedence:
2. Examine the current router IDs in the topology.
3. The router ID can also be seen in the output of the show ip protocols, show ip ospf, and show ip ospf interfaces commands.

Step 10: Verify OSPF operation

1. On the R1 router, use the show ip ospf neighbor command to view the information about the
2. On the R1 router, use the show ip protocols command to view information about the routing protocol operation.

Step 11: Examine OSPF routes in the routing tables

View the routing table on the R1 router. OSPF routes are denoted in the routing table with an O.

Step 12: Configure OSPF cost

1. Use the show ip route command on the R1 router to view the OSPF cost to reach the 10.10.10.0/24 network.
2. Use the show interfaces serial0/0/0 command on the R1 router to view the bandwidth of the Serial 0/0/0 interface.

Step 13: Reflection

What are some advantages of using OSPF as a routing protocol? Jawaban: supports VLSM and CIDR, uses cost metrics to choose the best path, and each router has a complete picture of the entire network.

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CCNA3 - Lab 6.2.4 Part B: Configuring and Verifying Multi-access OSPF

Step 1: Connect the equipment

Connect the Fa0/0 interface of each router to the switch using a straight-through cable. Three routers are sharing a common Ethernet multi-access network, 192.168.1.0/24. Each router will be configured with an IP address on the FastEthernet interface and a loopback address for the router ID.

Step 2: Perform basic configurations on the routers

Step 3: Configure and activate Ethernet and Loopback addresses

Step 4: Verify IP addressing and interfaces

1. Use the show ip interface brief or the show protocols command to verify that the IP addressing is correct and that the interfaces are active.
2. After all interfaces are verified, be sure to save the running configuration to the NVRAM of the router.

Step 5: Configure OSPF on the DR router

The DR and BDR election process takes place as soon as the first router has its interface enabled for OSPF on the multi-access network. If OSPF is already configured for an interface, this can happen as the routers are powered on.

Step 6: Configure OSPF on the BDR router

1. Configure the OSPF process on the router with the second highest router ID to ensure that this router becomes the BDR. Use the router ospf command in global configuration mode to enable OSPF on the R2 router.  What console message was displayed as a result of the OSPF commands on R2 and what does this mean? Jawaban: An OSPF adjacency message displayed indicating an adjacency was formed with the R3 router (Nbr 192,168.31.33). When the hello packet is received, the neighbor relationship is formed.

00:08:51: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.31.33 on

FastEthernet0/0 from LOADING to FULL, Loading Done

1. Use the show ip ospf interface command to verify that the OSPF has been configured correctly and that R2 is the BDR.

Step 7: Configure OSPF on the DRother router

1. Configure the OSPF process on the router with the lowest router ID last. This router will be designated as DRother instead of DR or BDR. Use the router ospf command in global configuration mode to enable OSPF on the R1 router
2. Use the show ip ospf interface command to verify that the OSPF has been configured correctly and that R1 is a DRother.

Step 8: Use the OSPF priority to determine the DR and BDR

1. Use the ip ospf priority interface command to change the OSPF priority of the R1 router to 255. This is the highest possible priority.
2. Use the ip ospf priority interface command to change the OSPF priority of the R3 router to 100.
3. Use the ip ospf priority interface command to change the OSPF priority of the R2 router to 0. A priority of 0 causes the router to be ineligible to participate in an OSPF election and become a DR or BDR.
4. Shut down and re-enable the FastEthernet0/0 interfaces to force an OSPF election. As the interfaces are shut down, the OSPF adjacencies are lost.

Step 9: Reflection

1. When the OSPF process starts, what happens if there is no active interface on the router? Jawaban: OSPF will not start.
2. What can be done to ensure there will be an active interface on a router? Jawaban: Configure a loopback interface.
3. How are the DR and BDR elected in an OSPF network? Jawaban: The DR is chosen with the highest OSPF priority value. The BDR is chosen with the second highest priority value. If the priority is the same, the OSPF election for DR is decided on the highest Router ID.
4. What OSPF interface priority value prevents a router from being elected as a DR? jawaban: 0

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CCNA3 - Lab 6.3.1 Configuring and Propagating an OSPF Default Route

Step 1: Connect the equipment

Connect each of the routers, switches, and hosts as shown in the topology diagram.

Step 2: Perform basic configurations on the routers

1. Connect a PC to the console port of the router to perform configurations using a terminal emulation program.
2. On Routers 1, 2, and 3, configure the hostname, console, Telnet, privileged passwords, and message-of-the-day banner and disable DNS lookups according to the addressing table and topology diagram.

Step 3: Configure the ISP router

1. Configure serial and loopback interfaces on Router 3.
2. On Router 3, configure a default route to both the 192.168.0.0 and the 192.168.1.0 networks.

Step 4: Configure the Area 0 OSPF routers

1. Configure loopback, FastEthernet, and serial interfaces on Router 1 and Router 2.
2. Save the running configuration to the NVRAM of each router.

 Step 5: Configure the hosts with the proper IP address, subnet mask, and default gateway

Each workstation should be able to ping the attached router. Troubleshoot as necessary. Remember to assign a specific IP address and default gateway to the workstation. At this point, the workstations will not be able to communicate with each other.

Step 6: Verify connectivity

Ping from R2 to both the ISP and R1 routers. Were the pings successful? Jawaban: yes

Step 7: Configure OSPF routing on both Area 0 routers

1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks are in Area 0.

Step 8: Test network connectivity

Ping the R1 host from the R2 host. Was it successful? Jawaban: yes

Step 9: Observe OSPF traffic

1. At the privileged EXEC mode, enter the command debug ip ospf events and observe the output. You may have to wait at least 40 seconds for the hello packet to be sent before observations can be recorded
2. Turn off debugging by entering no debug ip ospf events or undebug all.

Step 10: Create a default route to the ISP

On R2 only, enter a static default route.

R2(config)#ip route 0.0.0.0 0.0.0.0 200.20.20.1

Step 11: Verify the default static route

Verify the default static route by looking at the R2 routing table.

Step 12: Verify connectivity from the R2 router

1. Verify connectivity from R2 by pinging the ISP Serial 0/0/1 interface from the R2 router.

Is the ping successful? yes

1. Next, on the host attached to R2, open a command prompt and ping the Serial 1 interface on the ISP router.

Is the ping successful? Yes

1. This time, ping the loopback interface address of the ISP router, which represents the ISP connection to the Internet.

Step 13: Verify connectivity from the R1 router.

Verify the connection between the ISP and R1 by pinging the Serial 0/0/1 interface of the ISP router on R2.

Step 14: Redistribute the static default route

Propagate the gateway of last resort to the other routers in the OSPF domain. At the configure router prompt on R2, enter default-information originate.

R2(config-router)#default-information originate

Step 15: Reflection

1. How does OSPF reach networks outside of the domain? Jawaban: OSPF must know about the network or OSPF must have a default route.
2. What does a router use to generate a gateway of last resort? Jawaban: Default route.

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CCNA3 - Lab 6.3.2 Configuring OSPF Summarization

Step 1: Connect the equipment

1. Connect Router 1 to Routers 2 and 3 with serial cables. Connect Router 2 to Router 3 with a serial cable.
2. Connect the Router 2 Fa0/0 interface to the Switch 2 Fa0/1 interface using a straight-through cable.
3. Connect the Router 3 Fa0/0 interface to the Switch 3 Fa0/1 interface using a straight-through cable.
4. Connect Host 2 to Switch 2 and Host 3 to Switch 3 to the Fa0/2 interface using straight-through cables.
5. Connect Host 1 to the Router 1 Fa0/0 interface using a crossover cable.
6. Connect a PC with a console cable to perform configurations on the routers and switches.

Step 2: Perform basic configurations on the routers

1. Establish a console session with Router 1 and configure hostname, passwords, and interfaces as shown in the addressing table. Save the configuration.
2. Establish a console session with Router 2. Configure hostname, passwords, and interfaces according to the addressing table. Save the configuration.
3. Establish a console session with Router 3. Configure hostname, passwords, and interfaces according to the addressing table. Save the configuration.

Step 3: Perform basic configurations on the switches

1. Establish a console session with Switch 2 and configure hostname and passwords according to the addressing table. Save the configuration.
2. Perform a similar configuration on Switch 3, configuring the hostname and passwords as described for SW 2. Save the configuration.

Step 4: Configure the hosts with the proper IP address, subnet mask, and default gateway

1. Configure each host with the proper IP address, subnet mask, and default gateway for the network on which it resides. Host 1 should be assigned the address 209.165.201.1/24. Host 2 and Host 3 should be assigned IP addresses in the 192.168.10.0/28 and 192.168.10.32/28 networks respectively. All three PCs use the Fa0/0 interface of their attached router as their default gateway.
2. Each workstation should be able to ping the attached router. If the ping is not successful, troubleshoot as necessary. Check and verify that the workstation has been assigned the correct IP address and default gateway.

Step 5: Configure OSPF routing with default summarization

1. On Border, configure OSPF as the routing protocol with a process ID of 1 and advertise the appropriate networks.
2. Perform a similar configuration on R2, using the same process ID and advertising the appropriate networks. Remember to advertise the FastEthernet interface.
3. On R3, perform a similar configuration, using the same process ID and advertising the appropriate networks.

Step 6: Configure and redistribute a default route for Internet access

1. From the Border router to Host 1, the host simulating the Internet, create a static route to network 0.0.0.0 0.0.0.0, using the ip route command and the next hop interface. This will forward any unknown-destination address traffic to the PC simulating the Internet by setting a gateway of last resort on the Border router.
2. Border will advertise this route to the other routers if this command is added to its OSPF configuration.

Border(config)#router ospf 1

Border(config-router)#default-information originate

Step 7: Verify the routing configuration

1. View the routing table on Border.
2. View the routing tables on R2 and R3.

How is the pathway for Internet traffic provided in their routing tables? There is a gateway of last resort leading to R3, and the default route shows up as a distributed OSPF route.

Step 8: Verify connectivity

1. Simulate sending traffic to the Internet by pinging from the host PCs to 209.165.201.1.

Were the pings successful? Yes.

Verify that hosts within the subnetted network can reach each other by pinging between Host 1 and Host 2.

Were the pings successful? Yes.

Step 9: Configure OSPF summarization

1. Compute a summary route for the corporate subnetworks. The networks have been assigned contiguously:
2. Configure the summary route in router configuration mode, starting with area 0 range followed by the summary route and its mask.

Step 10: Recheck routing tables to verify the summarization

View the effects of summarization using the following commands: Think about your answers to the previous questions. What advantage do you see in using summarization in this network? Jawaban: This makes the job of the Border router simpler and easier, as it can represent the whole network with one route. The ISP does not care about individual subnets; its job is simply to provide Internet access to the area. Convergence will be improved, as Border will not have to issue updates on every problem on every subnet.

Step 11: Reflection

List three effects of using summarization within an OSPF area? Jawaban: smaller routing table, lower memory and processor requirements, fewer lookups needed.

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CCNA3 - Lab 7.2.3.3 Configuring and Verifying a PPP Link

Step 1: Connect the equipment

Connect Router 1 and Router 2 with a serial cable connecting both Serial 0/0/0 interfaces as shown in the topology diagram.

Step 2: Perform basic configuration on Router 1

Connect a PC to the console port of the router to perform configurations using a terminal emulation program. On Router 1, configure the hostname, IP addresses, and passwords as provided in the addressing table. Save the configuration.

Step 3: Perform basic configuration on Router 2

On Router 2, configure the hostname, IP addresses, and passwords as provided in the addressing table. Save the configuration.

Step 4: Show the details of Serial 0/0/0 interface on R1

Enter the command show interface serial 0/0/0 to view the details of the interface.

Step 5: Show the details of Serial 0/0/0 interface on R2

Enter the command show interface serial 0/0/0 to view the details of the interface.

Step 6: Turn on PPP debugging

Turn on the PPP debug function on both routers by entering debug ppp negotiation at the privileged EXEC mode prompt.

Step 7: Change the encapsulation type

Change the encapsulation type to PPP by entering encapsulation ppp at the interface Serial 0/0 configuration mode prompt on both routers.

Step 8: Show the details of Serial 0/0/0 interface on R1

Enter the command show interface serial 0/0/0 to view the details of the interface.

Step 9: Show the details of Serial 0/0/0 interface on R2

Enter the command show interface serial 0/0/0 to view the details of the interface.

Step 10: Verify that the serial connection is functioning

Ping from R1 to R2 to verify that there is connectivity between the two routers.

Step 11: Reflection

1. What command allows you to view the details of a specific interface? Jawaban: show interface serial 0/0/0 (or whichever interface you select).
2. When should you use the debug function in a router? Jawaban: when you want to troubleshoot or to view what is occurring in real time on the network. Caution should be used to minimize the negative impact debugging has on network performance.
3. What is the default serial encapsulation on a Cisco router? Jawaban: HDLC

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CCNA3 - Lab 7.2.5.3 Configuring and Verifying PAP and CHAP Authentication

Step 1: Connect the equipment

Connect Router 1 and Router 2 with a serial cable connecting both Serial 0/0/0 interfaces as shown in the topology diagram.

Step 2: Perform basic configuration on Router 1

1. Connect a PC to the console port of the router to perform configurations using a terminal emulation program.
2. On Router 1, configure the hostname, IP addresses, and passwords as provided in the addressing table. Save the configuration.

Step 3: Perform basic configuration on Router 2

On Router 2, configure the hostname, IP addresses, and passwords as provided in the addressing table. Save the configuration.

Step 4: Configure PPP encapsulation on both R1 and R2

Change the encapsulation type to PPP by entering encapsulation ppp at the interface Serial 0/0

configuration mode prompt on both routers.

R1(config-if)#encapsulation ppp

R2(config-if)#encapsulation ppp

Step 5: Verify PPP encapsulation on R1 and R2

Enter the command show interface serial 0/0 to verify the PPP encapsulation on R1 and R2.

Step 6: Verify that the serial connection is functioning

Ping from R1 to R2 to verify that there is connectivity between the two routers.

R1#ping 192.168.15.2

R2#ping 192.168.15.1

Step 7: Turn on PPP debugging

To display the authentication exchange process as it occurs, issue the command debug ppp

authentication at the privileged EXEC mode prompt.

R1#debug ppp authentication

R2#debug ppp authentication

Step 8: Configure PPP authentication on R1 with PAP

1. Configure the username and password on the R1 router.
2. In Cisco IOS releases 11.1 or later, PAP must be enabled on the interface because it is disabled by default. From the Serial 0/0/0 interface configuration mode prompt, enable PAP on the interface.

Step 9: Verify that the serial connection is functioning

Verify that the serial connection is functioning by pinging the serial interface of R2.

Step 10: Configure PPP authentication on R2 with PAP

1. Configure the username and password on the R2 router
2. In Cisco IOS releases 11.1 or later, PAP must be enabled on the interface because it is disabled by default. From the Serial 0/0/0 interface configuration mode prompt, enable PAP on the interface.

Step 11: Verify that the serial connection is functioning

Verify that the serial connection is functioning by pinging the serial interface of R1.

Step 12: Remove PAP from R1 and R2

Remove PAP from R1 and R2 by issuing the command no in front of the commands used to configure PAP.

Step 13: Configure PPP authentication on R1 with CHAP

1. f both CHAP and PAP are enabled, the first authentication method specified is requested during the link negotiation phase. If the peer suggests using the second method or simply refuses the first method, the second method is tried.
2. Save the configuration on R1 and R2 and reload both routers.
3. To display the authentication exchange process as it occurs, issue the command debug pppauthentication at the privileged EXEC mode prompt.
4. Configure the username and password on the R1 router.

Step 14: Configure PPP authentication on R2 with CHAP

Configure the username and password on the R2 router

Step 15: Verify that the serial connection is functioning

Verify that the serial connection is functioning by pinging the serial interface of R1.

Was it successful? Yes

Step 16: Verify the serial line encapsulation on R1

Enter the command show interface serial 0/0 to view the details of the interface.

Step 17: Verify the serial line encapsulation on R1

Enter the command show interface serial 0/0 to view the details of the interface.

Step 18: Turn off debugging on both R1 and R2

Turn off all debugging by issuing the undebug all command on both R1 and R2.

R1#undebug all

R2#undebug all

Step 19: Reflection

1. What is an advantage of using CHAP over PAP? Jawaban: CHAP is the preferred protocol because CHAP periodically verifies the identity of the remote node using a three-way handshake. CHAP provides protection against playback attack through the use of a variable challenge value that is unique and unpredictable. Because the challenge is unique and random, the resulting hash value will be unique and random.
2. Which PPP protocol is used for establishing a point-to-point link? Jawaban: LCP
3. Which PPP protocol is used for configuring the various Network Layer protocols? Jawaban: NCP

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CCNA Discovery 3 Module 9 Exam Answers Version 4.0

1. 
 
Refer to the exhibit. Based on the output shown, to which IP network should the workstations in the Support department belong? 
• 172.16.3.0 

2. 
 
Refer to the exhibit. A network administrator is doing proactive network maintenance. The administrator pings 192.168.1.100 and compares the results to the baseline data. Based on the comparison of the two pings, what is one possibility? 
• There are congestion problems on the network. 

3. 
 
Refer to the exhibit. Given the output generated by the debug ppp negotiation command, which statement is true? 
• The line protocol of the local router is now up. 

4. What is important to consider while configuring the subinterfaces of a router when implementing inter-VLAN routing? 
• The IP address of each subinterface must be the default gateway address for each VLAN subnet. 

5. 
 
Refer to the exhibit. A lab technician connects two routers together via a serial cable using the default interface configuration values. The interfaces are up; however, the technician is unable to ping between the two devices. What is the most likely problem? 
• No clock rate has been set on the DCE interface. 

6. 
 
Refer to the exhibit. Based on the output shown, why is VTP information unable to propagate the network? 
• The VTP domain names are different. 

7. The enterprise mail server software recently went through a minor update. A network administrator notices an excessive amount of traffic between a database server and the newly updated mail server, compared to the baseline data. What is the first action the administrator should do to investigate the problem? 
• Check the log to see what software components are producing the excess traffic. 

8. 
 
Refer to the exhibit. Users are reporting that they cannot access the Internet. Routers R1 and R2 are configured with RIP version 2 as shown. If R2 receives a packet with a destination address on the Internet, how is the packet routed? 
• The packet is routed to R1 and then forwarded out Fa0/0 on R1. 

9. 
 
Refer to the exhibit. Both routers are configured using RIPv1. Both routers are sending updates about the directly connected routes. R1 can successfully ping the serial interface of R2. The routing table on R1 does not contain any dynamically learned routes from R2, and the routing table on R2 shows no dynamically learned routes from R1. What is the problem? 
• VLSM is not supported by RIPv1. 

10. 
 
Refer to the exhibit. Host 192.168.1.14 is unable to download email from 192.168.2.200. After reviewing the output of the show running-config command, what problem is discovered? 
• The destination host address in an ACL statement is incorrect. 

11. An employee called the help desk to report a laptop that could not access a web-based application on the Internet. The help desk technician asked the employee to open a Windows command prompt and type the ipconfig /all command. Which problem-solving technique did the technician choose? 
• divide-and-conquer 

12. 
 
Refer to the exhibit. Based on the network diagram and the output shown, which statement is true? 
• The command was entered on router R1. 

13. 
 
Refer to the exhibit. An ACL is configured to prevent access by network 192.168.1.0 to network 192.168.2.0, but it is not working properly. What problem is discovered after observing the output of the show running-config command? 
• The ACL is applied to the wrong interface, but the right direction. 

14. 
 
Although all networks are reachable, the network administrator notices abnormal routing behavior after configuring OSPF on each router. According to the partial output from the debug ip ospf events command, which statement is true about the contents of the routing table in RA? 
• It will show network 172.16.3.0 learned from RB. 

15. A network at a large building failed, causing a severe disruption in business activities. The problem was eventually detected and resolved by replacing a piece of failed network equipment. Investigation led to the conclusion that a network design problem was the main cause of the disruption. Loss of a single piece of equipment should not have been able to cause such a large problem. What two terms best describe this type of design weakness? (Choose two.) 
• large failure domain 
• single point of failure 

16. 
 
Refer to the exhibit. The network administrator is troubleshooting the connectivity issue between RA and RB. According to the partial configuration, what is the cause of the problem? 
• password mismatch for PPP authentication 

17. 
 
Refer to the exhibit. ABC Company is using the 172.16.0.0/18 network. It is standard company practice to use the first 50 addresses for switches and servers and assign the last usable address to the router. The remaining addresses are assigned to the hosts. After assigning the addresses, the network technician tests connectivity from the host above and is not able to ping the router. What could be the problem? 
• The router interface is in the wrong subnet. 

18. 
 
Refer to the exhibit. A network administrator is troubleshooting a problem. No users are able to access the 10.10.2.0/24 network, but are able to access all other networks. Assuming R3 is configured correctly and based on the output shown, what is most likely the problem? 
• The EIGRP process number on R2 is incorrect.  

19. 
 
Refer to the exhibit. The network administrator correctly configures RTA to perform inter-VLAN routing. Using the show vlan command, the administrator verifies that port Fast Ethernet 0/4 is the first available port in the default VLAN on SW2. The administrator connects RTA to port 0/4 on SW2, but inter-VLAN routing does not work. What could be the possible cause of the problem with the SW2 configuration? 
• Port 0/4 is configured in access mode. 

20. 
 
Refer to the exhibit. The network administrator is unable to ping from the console of router R3 to host 10.10.4.63. What is the problem? 
• There is an addressing problem on the link between routers R2 and R3. 

21. 
 
Refer to the exhibit. A network administrator has implemented subnetting using the network 192.168.25.0 and a /28 mask. Workstation 1 is not able to ping with Workstation 2. What is a possible cause for this lack of communication? 
• Workstation 1 is not on the same network that the RTA router LAN interface is on. 

22. Which two statements describe when a network administrator should perform a network baseline? (Choose two.) 
• It should be performed when all switch Cisco IOS versions are upgraded. 
• It should be done when the network is performing at normal activity levels. 

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