A-level Computing 2009/CIE/Computer systems, communications and software/Data transmission and networking


 * (a) describe the characteristics of a local area network (LAN) and a wide area network (WAN)
 * (b) show an understanding of the hardware and software needed for a local area network (LAN) and for accessing a wide area network (WAN)
 * (c) describe basic network topologies (bus, star and ring) explaining the benefits and drawbacks of each topology

* /Networking/


 * (d) describe the different types of data transmission: serial and parallel; simplex, half duplex and full duplex modes
 * (e) explain the relationship between bit rates and the time sensitivity of the data
 * (f) recognise that errors can occur in data transmission; explain the use of parity checks, echoing and checksums in detecting and correcting these errors, and the use of parity blocks to aid self-checking

* /Data transmission/


 * (g) explain the difference between packet switching and circuit switching

* /Circuit switching and packet switching/


 * (h) define the term protocol
 * (i) describe the need for communication between devices, and between computers, and explain the need for protocols to establish communication links
 * (j) explain the need for both physical and logical protocols and the need for layering in an interface

* /Protocols/