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UNIT 8INTEGRATING THE COURSE ELEMENTS
LESSON 1A SMALL PEER-TO-PEER NETWORK Activities 1 Draw a peer-to-peer Ethernet network consisting of 12 nodes using two 8-port hubs. Show the hubs as being daisy-chained (cas-caded). Describe a typical node on this peer-to-peer network by answer the fol-lowing: 2 Describe the computer hardware (use current and reasonable val-ues): a Type and speed of CPU PC, 450mhz b Amount of RAM 64 mb c Amount of hard disk storage 4 gigabytes d Type of NIC (EISA or PCI) PCI e Type of cabling used to connect to the hub. Category5 UTP f Type of connectors on the cable. RJ45 3 Describe the software components: a Type of operating system Window 98 b Networking software installed TCP/IP c Default protocol BEUI 4 Fill in the appropriate protocol stack entries and Ethernet frame header entries corresponding to the protocol stack. Assume net-working software is TCP/IP. Eth IP TCP APPL Eth Extended Activities 1 If a lab is available, build, configure, and operate a peer-to-peer network. 2 Share the following resources between peers: a Files b Directories c CD-ROM d Floppy drive e Printers 3 Transfer files from the shares to other peers. In the case of a printer, print files to the print share. 4 Are there any other devices that can be shared? Discuss. 5 Use a Web search engine and find utilities available for a peer-to-peer networking environment. Also try www.download.com and www.shareware.com. LESSON 2NETWORK SERVERS AND SERVICES Activities A small group of users running a popular desktop operating system have outgrown their peer-to-peer network and wish to upgrade to a cli-ent/ server environment. In addition to transferring the company files over to a server, the users also require access to two laser printers, a high-end plotting device, and the Internet. Some of the users have requested that remote access from their home PCs be available on the new system. The printers and plotter all have a built-in TCP/IP stack and Ethernet NIC. They run a handful of standard applications, such as word processing, spreadsheets, and e-mail, as well as two custom applications for the plotting device. 1 Draw a network diagram illustrating the new client/server system, making sure all user requirements are fully met. Assume five users currently, with growth to four more users in the next six months. 2 Label all the components, both hardware and software. Include the server operating system as well as the clients operating system. Be sure to label the Internet access device as well. Note any additional software installed at the server and clients, such as networking soft-ware. Be thorough. You may choose to connect the clients to the server with either a hub or switch. Extended Activities 1 If a server is available, log on to a client/server network. 2 Enter a user name and password to access the server. Can a single user name and password be used for everyone? 3 Compare functions that a peer-to-peer network supports versus functions that a client/server supports. What are some functions/ support that are only available in a client/server environment? Dis-cuss. 4 Go to Web sites such as www.shiva.com and www.microsoft.com, and find information on virtual private networks (VPNs). What are VPNs used for? Discuss some applications. LESSON 3TRAFFIC ISOLATION IN A NETWORK Activities Consider the following diagram depicting a network: 1 What portion of the header will the switch use to move information to an Intranet Server? Ethernet header 2 What portion of the header will the router use to move information through the network? IP Header 3 What device(s) form the backbone of this network? Router Intranet Servers Router Hub Clients Clients Router Switch Hub Web Servers Hub Clients Clients Switch Hub HTTP Web Page Rqst Eth Eth TCP IP HTTP Web Page Rqst WAN WAN TCP IP Browser HTTP TCP IP Ethernet UTP Server HTTP TCP IP Ethernet UTP Consider the following network: 4 Is the switch performing port switching or segment switching? Segment with hubs, port with servers. 5 Trace the path from one of the clients on the left to the Web Serv-ers. Does traffic from this client reach the right-most hub? No; it will be isolated by the second switch. 6 Fill in the process name circles for the clients and the intranet serv-ers shown in the diagram. HTTP TCP IP Ethernet Extended Activities Perform the following exercise that demonstrates the differences between using hubs and switches. This exercise is intended for a Win-dows 95 peer-to-peer environment with sharing enabled on all clients. 1 Configure a network in a peer-to-peer, Windows 95 network using a hub. 2 Transfer a large file (>25 MB) from one client to another client with-out going through a central hub (disconnect workgroup hub from central hub if attached). Record the time it takes to transfer the file. 3 Transfer a large file to and from each client (or multiple clients) connected via a hub. Record the time it takes to transfer the file. Because multiple files are transferred simultaneously, average the time. 4 Tie all Workgroups hubs together into a central hub and transfer the same number of files between clients as in Step 3 of this exercise. In the WestNet lab you will have to tie the hub to the wall, which then goes to the patch panel. From the patch panel, tie into the hub. Record the time it takes to transfer the files. Discuss results. 5 Replace the central hub with a switch and repeat Step 4. Record the time it takes to transfer the files. Discuss results. LESSON 4CONNECTIVITY TO OTHER NETWORKS Activities 1 A router is a cost-effective solution to traffic isolation. True or False False. Routers are typically more expensive than switches. 2 A switch looks at the network address to decide where to forward the data. True or False False. A switch (level 2) looks at the Frame address to make a switching decision. 3 Routers are normally used to interconnect remote LANs. True or False True 4 A router that connects two local LAN segments (subnets) to a remote LAN has a total of three interface cards. True or False True 5 Where possible, it is more efficient to route traffic than switch traf-fic. True or False False. The opposite is true. Extended Activities Routers can be used to erect a "firewall" between parts of a network. The protocol used for routing by the Network Layers of the various communication architectures does not involve sending broadcast packets. By using routers, broadcast messages are kept behind a "fire-wall." When addressing and other problems occur, they are experi-enced by only a small group of users and are much easier to localize and resolve. 1 Why is it important to localize this type of traffic? Can a bridge also be used to isolate broadcast messages? Discuss. 2 Discuss the various common services that can be used to intercon-nect routers across WANs. What is considered "low-end" service? What is considered "high-end" service? 3 Use a Web search engine and find information on "backbone rout-ers." Compare various product offerings. LESSON 5INFORMATION FLOW FROM CLIENT TO WEB SERVER Activities Consider the following network: 1 Fill in the protocol stacks on the server and client, as well as the Ethernet frame with the appropriate information to complete the diagram. 2 Describe the flow of a request between the Web browser and Web server. 1. Hub broadcasts frame to all devices attached to hub including switch. 2. The switch forwards the frame to the router. 3. The router, based on the packet IP address, routes the information to the net-work with the web server. 4. The web server processes the informa-tion and replies to the client. 3 What kind of UTP cabling would be most likely be used in the LAN? Category 5 Intranet Servers Router Hub Clients Clients Router Switch Hub Web Servers Hub Clients Clients Switch Hub HTTP Web Page Rqst Eth Eth TCP IP HTTP Web Page Rqst WAN WAN TCP IP Browser HTTP TCP IP Ethernet UTP Server HTTP TCP IP Ethernet UTP 4 Could this LAN be operated at a speed of 100 Mbps, if it were run-ning at 10 Mbps, by just replacing the NICs? No, the hubs and switches would also need to be replaced. 5 The frame shown traveling between the routers has a WAN header. What happened to the Ethernet header? It was stripped (decapsulated) by the router and a new WAN header was added. 6 Describe the flow of information from Client A, across the WAN, to the Web server at the right of the network diagram. Client A sends a request for a Web page. The first hub would broad-cast the frame to all ports. The first switch would forward the frame to the router. The router would strip the link layer header and trailer and add the WAN header and trailer. The packet would be sent across the WAN. The final router would strip the WAN header and trailer and add a new LAN header and trailer. The new frame would be sent to the switch which would forward the frame and packet to the web server. 7 What type of WAN protocols could be used between the routers? Extended Activities Divide into focus groups. Discuss the following: 1 The differences between hubs, switches, and routers in light of the network configurations shown in this lesson. 2 Where network bottlenecks are likely to occur, and what might be done about alleviating potential network congestion (consider the server load). 3 Compare the Internet, intranets, and extranets. 4 List five applications that Web technologies address. 5 Where will the state of networking be three to five years from now. 1 List the four major components necessary to build a small peer-to-peer network. A computer and operating system capable of peer-to-peer network-ing Communication protocols A physical interface for each computer Physical connectivity components such as cables and connectors 1 What type of device is used with UTP cabling to create a star net-work configuration? Hub or Switch 2 Which of the following best describes the function of a MAC layer address: a Transmits a frame to the next NIC b Transmits a packet to the correct port c Transmits a frame to the final destination d Transmits a frame to the correct socket a Transmits a frame to the next NIC 3 Name the two types of fiber optic cables used to transmit data. Multimode and Singlemode 4 Name two types of cables commonly found in Ethernet networks. 10BaseT and 10Base2 5 Which of the following is found at the Network Layer of a protocol stack? a Datagram or packet b Frame c Bit or byte d LU a Datagram or packet 6 What is the difference between a LAN and WAN? Distance between devices in the network. 7 What does MAC stand for? Media Access Control 8 What does NIC stand for? Network Interface Card 9 What does MAU stand for? Multistation Access Unit 10 Name three common NOSs found in todays networks. Microsoft NT, Novell Network, AppleTalk 11 What unit of information does a bridge operate on? a Bit b Byte c Frame d Packet e Socket c Frame 12 What unit of information does a router operate on? a Bit b Byte c Frame d Packet e Socket c Packet 13 What does a repeater do? Repeats or regulates digital signals 14 Why is a hub used in a network? To concentrate network connections 15 Why is a switch used in a network? To provide isolation of LAN traffic and improve performance (copared to a hub-based network) 16 Is the OSI model still relevant? Explain. Yes, as a reference for understanding protocol layers, networking services, and networking products. 17 When would you use Frame Relay connectivity? To connect LANs to other LANs over a Metropolitan or wide area. 18 What is HTTP used for? To transfer documents between web clients and web servers. 19 Which will transmit a light signal the farthest distance? a Multimode cabling b Single-mode cabling c UTP cabling d STP cabling b 20 In a client/server arrangement, where are the requests normally generated? a Client b Server c Either of the above d NIC a |