Welcome, in this new unit we are going to see the classification of networks in detail.
They are divided in three categories:
- According to its coverage:
- PAN (Personal area network): is a network of computers used for communication between computer devices (including personal digital devices) close to one person. The scope of a PAN is
of some meters. They can be connected to USB and FireWire cables from the computer.
A wireless personal area network (WPAN) is can also make it possible with networks such as IrDA and Bluetooth.
- LAN (local area network): a network that is limited to an area such as one room, a single building or one warehouse. A large LAN is usually divided into logical segments smaller groups called working groups.
- MAN (metropolitan area network): a network that connects the networks of two or more buildings but does not extend beyond the boundaries of a city.
- WAN (World Wide Area Network): it is a network that covers a wide geographical area. Internet is a WAN.
When you have finished of reading and understanding this part and the previous unit, go to Test 1.
- According to its topology: the topology or logical form of a network is defined as how to wire the cable to individual workstations
- Bus: in a bus network all the workstations, servers and printers are joined to one cable (the bus). At each end of the cable a terminator is fitted to stop signals reflecting back down the bus.
- Star: in a star network each device on the network has its own cable that connects to a switch or hub. A hub sends every packet of data to every device, whereas a switch only sends a packet of data to the destination device.
- Ring: in a ring network each device (workstation, server, printer) is connected to two other devices, this forms a ring for the signals to travel around. Each packet of data on the network travels in one direction and each device receives each packet in turn until the destination device receives it.
- Hybrid: bus, star and ring topologies are sometimes combined to form hybrid networks.
- Hierarchical: the nodes are placed in the form of a tree. It is similar to a series of networks in star interconnected, with the difference that it does not have a central node but a node Trunk, usually occupied by a hub or switch, from which branch out the other nodes. It is a variation of the network in bus, the failure of a node does not communication is interrupted because the same communications.
To conclude this section, you should reflect on advantages and disadvantages of main topologies (bus, star and ring).
Check your answer on Document 1.
- According to its functional relation:
- Client-Server: the server is a specific machine that uses a developed operating system especially for this type of network. The workstations share resources vvailable from this server. The execution of tasks is divided between the Client (or station) and server. This type of network provides better performance and the most appropriate levels of security for the network professional work.
- Peer to Peer: it is a type of network where all the equipment connected can play the role of server and workstation at the same time. In this case, if someone want to share a resource offers it to others. This is a type of network for simple jobs, where the volume of information exchanged is small and security is not a critical factor.
Finally, go to Test 2 and check your performance in these two last units.