A-level Computing 2009/AQA/Problem Solving, Programming, Operating Systems, Databases and Networking/Communication and Networking

Communication Methods
Baud, bit rate,	bandwidth, latency Asynchronous data transmission Start and stop bits Odd and even parity Handshaking Protocol Baseband and Broadband
 * Define both serial and parallel transmission methods and describe where they are used
 * Consider the effect of distance on the transmission of data.
 * Define	these terms.
 * Differentiate between baud and bit rate.
 * Consider the relationship between bit rate and bandwidth.
 * Define	asynchronous data transmission.
 * Describe the purpose of start and stop bits in asynchronous data transmission.
 * Explain the use of parity checks.
 * Explain what is handshaking in the context of data transmission.
 * Explain what is meant by a protocol in this context.
 * Define each mode of network operation and describe where each is appropriate.

Networks
Networks Local Area Networks & Wide Area Networks Network adapter Topology (Bus & Star) Network	Segment Peer-to-peer networking & Server-based networking Thin client computing & Web services Wireless networking (Wi-Fi & Bluetooth) Inter-networking Routers	particularly, Gateways
 * Contrast wide area and local area networks
 * Define the term topology.
 * Differentiate between physical and logical network topologies
 * Describe in general terms the operation of these networks.
 * Compare the advantages and disadvantages of each.
 * Candidates should be able to compare local area networking with standalone operation.
 * Define	the term and explain why local-area networks based on a	bus topology are segmented.
 * Explain these terms and describe situations where these might be used.
 * Compare and contrast thin client computing (software as a service, AJAX, Web 2.0, etc) vs rich client computing (client-server, peer-to-peer), web services as examples of ‘systems architectures’.
 * Radio-based LAN protocols for connecting mobile/portable devices.
 * Explain the meaning of the term inter-networking.
 * Define	these and consider where and why they are used.
 * Consider how routing is achieved across the Internet and how local area networks are connected to the Internet via gateways.
 * Consider how a	subnet	mask is	used to	identify the network identifier part of an IP address.
 * Be familiar with the role of MAC addresses in routing packets/frames.
 * Distinguish between routable and non-routable IP addresses.

Server Side Scripting
Common Gateway Interface (CGI)

Server-side scripting – the basis of dynamic web page content.

Practical experience of writing simple server-side scripts.

Accessing data from a DBMS using server-side scripts.

Internet Security
Firewalls Encryption Digital Signatures and Digital	Certificates Virus detection Computer Security Procedures
 * Packet filtering.
 * Proxy	Server.
 * Private/Public key encryption.
 * How they are obtained and used.
 * Discuss worms, spam, phishing, pharming as well as viruses, also vulnerabilities that these exploit and how to address them through improved code quality, monitoring, protection.
 * Authentication
 * Authorisation
 * Accounting.