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A-level Computing/AQA/Problem Solving, Programming, Operating Systems, Databases and Networking/Communication and Networking
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Communication Methods
A-level_Computing/AQA/Problem_Solving,_Programming,_Operating_Systems,_Databases_and_Networking/Communication_and_Networking/Communication_Methods Communication Methods
Specification: Communication Methods
Define both serial and parallel transmission methods and describe where they are used
Consider the effect of distance on the transmission of data.
Baud, bit rate, bandwidth, latency
Define these terms.
Differentiate between baud and bit rate.
Consider the relationship between bit rate and bandwidth.
Asynchronous data transmission
Define asynchronous data transmission.
Start and stop bits
Describe the purpose of start and stop bits in asynchronous data transmission.
Odd and even parity
Explain the use of parity checks.
Handshaking
Explain what is handshaking in the context of data transmission.
Protocol
Explain what is meant by a protocol in this context.
Baseband and Broadband
Define each mode of network operation and describe where each is appropriate.
Networks
A-level Computing/AQA/Problem Solving, Programming, Operating Systems, Databases and Networking/Communication and Networking/Networks A-level Computing/AQA/Problem Solving, Programming, Operating Systems, Databases and Networking/Communication and Networking/Wireless_Networks Networks Wireless Networks
Specification: Networks
Networks
Local Area Networks & Wide Area Networks
Contrast wide area and local area networks
Network adapter
Topology (Bus & Star)
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.
Network Segment
Define the term and explain why local-area networks based on a bus topology are segmented.
Peer-to-peer networking & Server-based networking
Explain these terms and describe situations where these might be used.
Thin client computing & Web services
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’.
Wireless networking (Wi-Fi & Bluetooth)
Radio-based LAN protocols for connecting mobile/portable devices.
Inter-networking
Explain the meaning of the term inter-networking.
Routers particularly, Gateways
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
A-level_Computing/AQA/Problem_Solving,_Programming,_Operating_Systems,_Databases_and_Networking/Communication_and_Networking/Server-side_scripting Server-side scripting
Specification: 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
A-level_Computing/AQA/Problem_Solving,_Programming,_Operating_Systems,_Databases_and_Networking/Communication_and_Networking/Internet_Security Internet security
Specification: Internet Security
Firewalls
Packet filtering.
Proxy Server.
Encryption
Private/Public key encryption.
Digital Signatures and Digital Certificates
How they are obtained and used.
Virus detection
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.
Computer Security Procedures
Authentication
Authorisation
Accounting.