Tag Archives: Hub

1. Computer Systems, Computing Higher, Homework

Homework – Networks

Topics 5 and 6 – Networking

  1. Explain the difference between LAN’s and WAN’s with reference to transmission media, bandwidths and geographical spread. (2)
  2. Explain the difference between a mainframe computer with terminals and a network of computers. (2)
  3. Explain the differences between client server and peer-to-peer networks. (2)
  4. On a LAN describe the functions of file, print and web servers. (2)
  5. Describe a bus topology in terms of nodes and channels. Describe the consequences of failure of a node and a channel. (2)
  6. Describe the functions of a hub, switch and router on a network with particular reference to the differences between a hub and a switch. (3)
  7. Explain why a network computer needs a network interface card (NIC). (1)
  8. Explain briefly why networks are becoming increasingly widespread. (2)
  9. Explain how a virus may be spread to a computer and how it then may take effect. (2)
  10. The access a user has on the network depends on their permissions. Explain what is meant by permissions giving as an example the permissions you may have on your own folder and a shared folder on the network. (2)
Total Marks 20
1. Computer Systems, Computing Higher

Hub / Switch Comparison

Hub

  • A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.
  • Cheap to purchase and install
  • Problem – All devices on the network share the same bandwidth

Switch

  • Will look at traffic it receives and based on the destination address it will direct the traffic to the port.
  • Devices don’t share the same bandwidth. The network will not be slowed down.
  • Packet is delivered to address port. Problem – Require additional set-up and expensive to purchase.
1. Computer Systems, FAQ, Revision

FAQ – Hub or Switch

Simple description  of the functions  and  uses of a hub, switch and router

  • Hub
    • A Hub is a multi-port repeater. That means that data coming into one port is sent out of all other ports. This can result in congestion on the network as machines are swamped with data that id not for them, resulting in a slow down of network performance. A 100Mbps hub shares this with all machines, so each machine only gets a fraction of the speed.
  • Switch
    • A switch keeps a database of each machine on the network and which port of the switch they are connected to. These collision domains are controlled by the switch, which then results in a reduction of the number of collisions increasing the overall speed of the network. A 100Mbps switch gives each machine 100Mbps.
  • Router
    • A router is a device with two network cards that is responsible for routing data from one network to another. It does this by keeping track of IP addresses of computers on the networks and forwarding packets appropriately.

Remember the warriors of the net video is a good lead in, but look up the terms online.

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