1.5 System Architecture - Network topologies, protocols and layers

1.5 System Architecture - Network topologies, protocols and layers

1. What is a network?

   • A computer network is a number of computers linked together to allow them to share data.

2. Topologies

   • Star Topologies
     • In a star network, each device is connected by an individual cable directly to the server. Star networks are usually the layout of choice in schools and offices because they tend to be the most reliable of the topologies.
       • Used in Schools
   • Mesh Topologies
     • In a mesh network, each device is connected to each other

3. Encryption

   • Encryption is a method of scrambling data with a key code which makes no sense. On an open or public WiFi network anyone can join and sniff out packets of data from other users. Therefore encryption is used. If intercepted the data will have no meaning In order to read the data the user is required to decrypt the data using the key.

4. Protocols

   • HTTPS = Hyper text transfer protocol secure which is a more secure HTTP.
   • HTTP = Hyper text transfer protocol which are rules used when transferring data.
   • TCP = Transmission Control Protocol
     • FTP = File transfer protocol which are rules which have to be followed when transferring files.
     • POP = Post Office Protocol which is rules followed when receiving emails on a mail server

5. Layers

   • There are a number of tools used by developers and computer scientists, but the easiest is the idea of layers. Data can be modified without affecting different layers, network components are standardised and troubleshooting is easier if error occurs