Networking case-projects 3

Case Project 3-1 Old-Tech Corporation has 10 computers in its main office area, which is networked in a star topology using 10 Mbps Ethernet hubs and wants to add five computers in the manufacturing area. One problem with the existing network is data throughput. Large files are transferred across the network regularly, and the transfers take quite a while. In addition, when two or more computers are transferring large files, the network becomes unbearably slow for users. Adding the manufacturing computers will only make this problem worse and result in another problem. Because the ceiling is more than 30 feet high, there’s no easy way to run cables to computers, and providing a secure pathway for cables is next to impossible. Devise a solution to this company’s networking problems. As part of your solution, answer the following questions:

  • What changes in equipment are required to bring this company’s network up to date to solve the shared-bandwidth problem?

Use a big ladder and run the cables. If using a ladder is not a good option, then wireless access points could be used. Cables could be run across the ceiling (only a few because you wouldn’t need a ton of access points). Or an indoor point-to-point connection could be used with no data loss using equipment like ubiquiti nanobeams. Alternatively, wireless repeaters could be used but you would lose some network speed. Indoor point to point connections can be set up as long as the access point and station(s) aren’t too close to each other. Additionally, you can replace the hubs with switches. Probably gigabit switches with appropriate cat cables. There are 10Gb switches and ethernet cards if one gigabit is not enough. Although a wireless point-to-point connections wouldn’t really be able to transmit anywhere near 1Gb or higher. There are really power pieces of equipment for that, but I don’t think they are meant for that close of proximity. Also, the firewall traffic shaping could manage how much bandwidth a computer or other network device can use so if something is regularly causing issues it could be limited so it doesn’t use 100% of the wan connection or a lot of the lan connection.

  • What topology and which type of device can be used in the manufacturing area to solve the cabling difficulties?

Multiple star topologies (connecting to various switches) are fine but they’d want to use a switch that could handle all the traffic. Perhaps a switch with a 10Gb trunk ports and single gigabit ethernet ports.

 

Case Project 3-2 EBiz.com has 250 networked computers and five servers and uses a star topology wired network to reach employees’ offices, with a bus interconnecting three floors in its office building. Because of a staggering influx of Internet business, the network administrator’s task is to boost network performance and availability as much as possible. The company also wants a network design that’s easy to reconfigure and change because workgroups form and disband frequently, and their membership changes regularly. All computers must share sensitive data and control access to customer files and databases. Aside from the customer information and billing databases, which run on all servers, employees’ desktop computers must run standard word-processing and spreadsheet programs. Use the following write-on lines to evaluate the requirements for this network. After you finish, determine the best network topology or topology combination for the company. On a blank piece of paper, sketch the network design you think best suits EBiz.com’s needs. Remember: High performance and easy reconfiguration are your primary design goals!

  • What type of topology should be used in this network?
    • Sounds like the way they have it configured is fine. I guess it depends where on the network congestion could possibly be. The bus would have to handle a lot of data potentially so 10 gig trunk ports on the switches connected to it would probably be good. Then the servers and computers could connect to those switches. Obviously if 50 people decide to transfer files to a different floor over that bus then that would max the bandwidth of that bus. So, a faster bus would have to be used or multiple buses with traffic divided between them. Fiber optics might be optimal for the bus to increase speed. You could have 100Gb bus that way.
  • Will the network be peer to peer or server based?
    • Server based would be recommended due to the size of the network
  • How many computers will be attached to the network?
    • 255, but many more could be.
  • What kind of networking device is easiest to reconfigure? What kind offers the best access to the network medium’s bandwidth between pairs of devices?
    • Switches are pretty easy. You can reconfigure all the ports at once, setting up vlans for all of them or various kinds of rules. Additional switches can also be added to the switch stack for ‘easy’ expandability.
    • Switches would be good for guaranteeing bandwidth between lan devices. For example, there are gigabit switches that can handle 1gb sending/receiving on all 48 ports at the same time. So 96gbits total. So, all transfers and downloads would have up to 1gb throughput.

Case Project 3-3 ENorm, Inc. has two sites in Pittsburgh that are four miles apart. Each site consists of a large factory with office space for 25 users at the front of the factory and up to 20 workstations in two work cells on each factory floor. All office users need access to an inventory database that runs on a server at the Allegheny Street location; they also need access to a billing application with data residing on a server at the Monongahela site. All factory floor users also need access to the inventory database at the Allegheny Street location.

Office space is permanently configured, but the manufacturing space must be reconfigured before each new manufacturing run begins. Wiring closets are available in the office space. Nothing but a concrete floor and overhead girders stay the same in the work cell areas. The computers must share sensitive data and control access to files. Aside from the two databases, which run on the two servers, office computers must run standard word-processing and spreadsheet programs. Work cell machines are used strictly for updating inventory and quality control information for the Allegheny Street inventory database. Workstations in the manufacturing cells are switched on only when they’re in use, which might occur during different phases of a manufacturing run. Seldom is a machine in use constantly on the factory floor.

Use the following write-on lines to evaluate the requirements for this network. After you finish, determine the best network topology or topology combination for the company. On a blank piece of paper, sketch the network design you think best suits ENorm, Inc.’s needs.

  • Will the network be peer to peer or server based?
    • Server based, lots of people, and computers may not be on in certain areas at certain times. I’d have the two location be on the same lan via an IPsec VPN tunnel so they’d be able to access each other’s servers. They could communicate via a point to point connection if dishes on their roofs have line of sight.
  • How many computers will be attached to the network?
    • It doesn’t say how many floors there are so it could be 1000 for all I know.
  • What topology works best for the offices, given the availability of wiring closets?
  • They could have wireless and ethernet on a star topology.
  • What topology works best for the factory floor, given its need for constant reconfiguration?
  • Wireless in star. They could put access points on the girders. They’d need access points on each floor due to concrete.