Level 3 Technical Level IT: CYBER SECURITY IT: NETWORKING IT: PROGRAMMING IT: USER SUPPORT Y/507/6424 Unit 1 Fundamental principles of computing

Level 3 Technical Level IT: CYBER SECURITY IT: NETWORKING IT: PROGRAMMING IT: USER SUPPORT Y/507/6424 Unit 1 Fundamental principles of computing Mark scheme June 2019 Version 1.0: Final *196AY/MS* Mark schemes are prepared by the Lead Assessment Writer and considered, together with the relevant questions, by a panel of subject teachers. This mark scheme includes any amendments made at the standardisation events which all associates participate in and is the scheme which was used by them in this examination. The standardisation process ensures that the mark scheme covers the students’ responses to questions and that every associate understands and applies it in the same correct way. As preparation for standardisation each associate analyses a number of students’ scripts. Alternative answers not already covered by the mark scheme are discussed and legislated for. If, after the standardisation process, associates encounter unusual answers which have not been raised they are required to refer these to the Lead Examiner. It must be stressed that a mark scheme is a working document, in many cases further developed and expanded on the basis of students’ reactions to a particular paper. Assumptions about future mark schemes on the basis of one year’s document should be avoided; whilst the guiding principles of assessment remain constant, details will change, depending on the content of a particular examination paper. Further copies of this mark scheme are available from Copyright information For confidentiality purposes acknowledgements of third-party copyright material are published in a separate booklet which is available for free download from after the live examination series. Copyright © 2019 AQA and its licensors. All rights reserved. Level of response marking instructions Level of response mark schemes are broken down into levels, each of which has a descriptor. The descriptor for the level shows the average performance for the level. There are marks in each level. Before you apply the mark scheme to a student’s answer read through the answer and annotate it (as instructed) to show the qualities that are being looked for. You can then apply the mark scheme. Step 1 Determine a level Start at the lowest level of the mark scheme and use it as a ladder to see whether the answer meets the descriptor for that level. The descriptor for the level indicates the different qualities that might be seen in the student’s answer for that level. If it meets the lowest level then go to the next one and decide if it meets this level, and so on, until you have a match between the level descriptor and the answer. With practice and familiarity you will find that for better answers you will be able to quickly skip through the lower levels of the mark scheme. When assigning a level you should look at the overall quality of the answer and not look to pick holes in small and specific parts of the answer where the student has not performed quite as well as the rest. If the answer covers different aspects of different levels of the mark scheme you should use a best fit approach for defining the level and then use the variability of the response to help decide the mark within the level, ie if the response is predominantly level 3 with a small amount of level 4 material it would be placed in level 3 but be awarded a mark near the top of the level because of the level 4 content. Step 2 Determine a mark Once you have assigned a level you need to decide on the mark. The descriptors on how to allocate marks can help with this. The exemplar materials used during standardisation will help. There will be an answer in the standardising materials which will correspond with each level of the mark scheme. This answer will have been awarded a mark by the Lead Examiner. You can compare the student’s answer with the example to determine if it is the same standard, better or worse than the example. You can then use this to allocate a mark for the answer based on the Lead Examiner’s mark on the example. You may well need to read back through the answer as you apply the mark scheme to clarify points and assure yourself that the level and the mark are appropriate. Indicative content in the mark scheme is provided as a guide for examiners. It is not intended to be exhaustive and you must credit other valid points. Students do not have to cover all of the points mentioned in the Indicative content to reach the highest level of the mark scheme. An answer which contains nothing of relevance to the question must be awarded no marks. The following annotation is used in the mark scheme: ; - means a single mark // - means alternative response / - means an alternative word or sub-phrase A. - means acceptable creditworthy answer R. - means reject answer as not creditworthy NE. - means not enough I. - means ignore DPT. - in some questions a specific error made by a candidate, if repeated, could result in the candidate failing to gain more than one mark. The DPT label indicates that this mistake should only result in a candidate failing to gain one mark on the first occasion that the error is made. Provided that the answer remains understandable, subsequent marks should be awarded as if the error was not being repeated. Question Guidance Mark 01 Mark is for AO4 NOT; R. more than one box ticked 1 02 Mark is for AO5 230 bytes; R. more than one box ticked 1 03 Mark is for AO5 binary; R. more than one box ticked 1 04 Mark is for AO3 examines all packets of data coming into the network; R. more than one box ticked 1 05 Mark is for AO5 high-level; R. more than one box ticked 1 Question Guidance Mark 06.1 1 mark for AO4 Output; R. More than one word for the answer 1 06.2 1 mark for AO4 The output from the ANPR is a vehicle registration number; A. Make/model of car; other answers which indicate a unique vehicle is identified. A. Letters/numbers. A. Any other creditable answer. 1 Question Guidance Mark 07.1 2 marks for AO3 Guidance for examiners: Utilities generally fit into the following categories: • disk utilities • system utilities • storage/file management utilities. 1 mark for each utility named, such as: • anti-virus • (systems) backup • systems optimiser, eg memory cleaner/management • system information/profiler • system preferences • disk formatter/Disk (Utility) • disk cleaner // clean up tools • file management • text editor • graphic editor • registry cleaner/editor • screensaver • screenshot/snipping tools/utilities • data/file/disk compression/compressing • task manager/Activity Monitor • command line interface/Terminal 2 07.2 4 marks for AO3 1 mark for each of the following points. (If both points are not included, a maximum of 3 marks may be awarded): • over time files may become fragmented; • a disk defragmenter optimises space; 1 mark for each expansion point, such as: • space for storage becomes less contiguous; • as files are deleted // new files are added; • a disk defragmenter analyses stored data on a drive // scans a drive for parts of files that aren’t stored in the same area; • moving/rearranging (parts of) files to contiguous areas of storage; • therefore storage space is increased; • read/write times are reduced; as read/write head needs to move less/wait less for next cluster to be found; A. Any other creditable answer. 4 Question Guidance Mark 08 3 marks for AO4 Max. 2 marks if no example given. 1 mark for each point, such as: Causes of failure: • overheating; • processor malfunction; • storage disk failure; • memory component; • server overload; 1 mark for each explanatory point, such as: • prevent loss of data; • gives time to react/act to prevent failure; • preventative replacement of components; • cost of systems failure; • potential reputational damage; 3 Question Guidance Mark 09.1 1 mark for AO3 A code library is (a set of) common routines//collection of (pre-written) code; 1 09.2 3 marks for AO3 Maximum 3 marks from: • It is useful because the code for each routine is already written; so that a programmer does not have to spend time creating code to do that task; • The code can be used by many programs // adds additional functionality; • The code can be reused by a programmer; • Reduce duplication of code; • Code is known to be error free; • Code is pre-compiled, (so program compilation is quicker); • Example of library module/function (eg import random); description of use; A. explanations that comment on standard behaviour of code. A. Any other creditable answer. 3 09.3 1 mark for AO5 Any relevant programming language, for example: • C • C++ • C# • Java • JavaScript • Ruby • Visual Studio • CSS 1 Question Guidance Mark 10.1 2 marks for AO4 1 mark for calculating each expression accurately. Expression 1 25.5; Expression 2 42; 2 10.2 1 mark for AO4 16.5; A. -16.5; A. error carried forward from Question 09.1 1 11.1 1 mark for AO1 Maximum of 1 mark from: • ensures resilience of system; • if one computer breaks down the other will continue; • you need to make sure that critical systems keep running; • relevant references to pipelining; • relevant references to simultaneous calculations / coordinated computations; A. Any other creditable answer. 1 11.2 1 mark for AO1 Maximum of 1 mark from: • A core is the same as a CPU/processor; • It carries out/processes instructions/tasks; A. Any other creditable answer. 1 11.3 2 marks for AO1 1 mark for any of the following points up to a maximum of 2 marks: • the forecast needs to be calculated very quickly; • because result needed before actual event occurs; • weather forecasting requires a lot of computing power/resources to carry out the millions of calculations required // to react to constant changes; • more calculations can be carried out at the same time // at a faster rate; • intensive programming requirements of complex software; R. repetition of points in 11.1 and 11.2 2 Question Guidance Mark 12.1 9 marks for AO3 Indicative content: Memory management • Manage the computer’s memory Processor management • Manage the computer’s processor(s)CPU • Schedules which processes are to be executed Input/output management • Manages input/output devices • Interacts with/manages/handles the (automatic) installation of device drivers • Handles peripheral device interrupts • Control network communication • Allow devices to send and receive data Managing storage • Manage secondary storage devices • Loading data and programs into the computer’s memory • Storage space management (disk quotas) • To ensure that storage space is allocated fairly and efficiently to specific tasksusers Managing security • User authentication • To make sure that users must prove who they are to access the system • Protect against malware • Block access to specific vulnerable operations or system areas. For example, software can only be installed with admin access. 9 Managing applications • Control access to applications • Prevent users or processes using unauthorised programs // allow users or processes to use authorised programs • Control application access • Prevent/allow an application access to data (or devices) A. User interface; 12.2 1 mark for AO3 Maximum of 1 mark from: • Linux is free/Unix is not free; • Linux is completely open source (source code is available)/Unix is proprietary (source code is not available); • Linux is customisable; • Linux is extensible; • Linux works on a wider range of platforms than most Unix environments; • Common kernel in Linux distributions (not in Unix); • Linux operates using the Ext3 file system while Unix does not; A. Any other creditable answer. 1 12.3 1 mark for AO3 Maximum of 1 mark from: • Each distributor wants to add functionality // (as Linux is open source) is source code can be customised (and redistributed); • Each distribution is aimed at a different market; A. Any other creditable answer. 1 Question Guidance Mark 13.1 2 marks for AO2 Only credit steps from one process. 1 mark for any valid step. Maximum 2 marks: BIOS steps: • interrupt Boot process to access BIOS screen; • access Boot Menu section of BIOS; • change order of access to bootable media to set USB/removable devices; • save changes; EFI/UEFI steps may vary from above and include: Windows: • press recovery key; • add new boot option; • disable secure boot option; MacOS: • hold down a key (eg alt) at boot; which brings up a menu where the boot drive can be selected; • change startup disk in system preferences; and reboot the computer; • restart computer in target disk mode; A. Any other creditable answer. 2 13.2 4 marks for AO2 1 mark for each of the following points to a maximum of 4 marks: • supports larger capacity boot devices; UEFI supports drive capacities larger than 2 TB; • faster boot times; UEFI is modular so only loads the components necessary at boot time; • better security; operating system can be checked for validity (malware check); • secure booting; supports Secure Boot; • provides GUI // (sometimes) mouse controlled; • provides a shell environment (to execute other UEFI applications) • supports networking functionality; for remote UEFI support; • independent CPU drivers / architecture; • (modular design) can be extended later on (as hardware advances); • supports unlimited partitions; • other expansion point; A. Any other creditable answer. 4 Question Guidance Mark 14 2 marks for AO2 1 mark for an advantage, such as: • speeds up processes within the CPU; • instruction throughput increases / less delay between completed instructions; • an improvement on instructions per time unit executed / the cycle time of the processor is reduced; • (as you are able to pump in more instructions) you get a significant improvement in processor speed // pipelining increases the overall performance of the CPU; • (increase in the number of pipeline stages) means more instructions can be executed simultaneously // a batch of instructions can be processed more quickly; R. (individual) instructions are executed/processed more quickly. 1 mark for a disadvantage, such as: • more expensive to manufacture; • bottlenecks; • increased instruction latency; • throughput is difficult to predict; • pipelining is not suitable for all kinds of instructions; • (the longer the pipeline) the worse the problem of hazard for branch instructions; • hazards such as stall / flush / read-after-write / can lose the order of instructions; A. software needs to be specially written to take advantage of pipelining. 2 15 3 marks for AO3 If points given are only for one type of interrupt then a maximum of 2 marks. Maximum of 3 marks from: • An IRQ does not require an immediate response/can be dealt with later/can be ignored (temporarily); • An IRQ is a request from a device for a response; • An IRQ is dealt with at the end of the current instruction cycle; • An NMI does require an immediate response/can’t be ignored; • An NMI is a type of (hardware) interrupt that prioritises certain processes; • An NMI cannot be masked/ignored; • When an NMI is received the current instruction cycle is suspended; Maximum of 1 mark for correct example of interrupt generator, for example keypress A. Any other creditable answer. 3 Question Guidance Mark 16.1 2 marks for AO3 Maximum of 2 from: malware is malicious software; that can infect a computer; causing damage or nuisance; clarifying example; 2 16.2 1 mark for AO3 Maximum of 1 from: • virus; • worm; • trojan; • spyware; • rootkit; • keylogger (malware); A. Any other creditable answer. R. Ransomware R. A list of possible answers (credit only given to first answer) 1 16.3 3 marks for AO3 Software that is not updated can have security flaws; that can be exploited by criminals; Regular updating can prevent this; A. Answers explaining how the software inventory may be used to monitor updating of software. A. Any other creditable answer. 3 Question Guidance Mark Level Description Mark Range 3 Candidate named several pieces of security software and has explained all or discussed some and clearly understood their effectiveness in preventing attacks and minimising the after effects of attacks. 7 − 9 2 Candidate has named some pieces of security software. There is some explanation or a description of how all the software may be effective in preventing attacks or minimising the effects of attacks. 4 − 6 1 Candidate has named some security software. There may be no, or little, description of the software. 1− 3 No creditworthy material 0 Question Guidance Mark 17 4 marks for AO1 10 marks for AO2 1 mark for AO3 Indicative content: • Evaluation of need • Task to be performed • Laptop or desktop • Apple or Windows • Budget • Components such as processor, RAM, different manufacturers • Desktop – build or buy • Comparing manufacturers and specifications • Graphics capability/memory • Output required, eg HD/Ultra HD (and graphics card powerful enough for monitor) • Trade off (in price) between faster CPU and more memory • Software requirements which dictate power needed eg games vs office software. Operating system etc. • Integrated motherboard, or more powerful with separate sound or graphics cards etc • Expansion ports and speed (Gigabit) or Wi-Fi version • Or lack of expansion ports (Apple, all Thunderbolt) which requires breakout box for legacy connections (USB, Ethernet etc) • Internal or external storage (types of storage medium, pros and cons) 15 Assessment Outcomes Question AO1 AO2 AO3 AO4 AO5 Question Total SECTION A 1 4g (1) 1 2 5c (1) 1 3 5f (1) 1 4 3n (1) 1 5 5e (1) 1 6.1 4e (1) 1 6.2 4e (1) 1 7.1 3d (2) 2 7.2 3d (4) 4 8 4e (3) 3 9.1 3c (1) 1 9.2 3c (3) 3 9.3 5g (1) 1 10.1 4f (2) 2 10.2 4f (1) 1 11.1 1d (1) 1 11.2 1c (1) 1 11.3 1c (1) 1d (1) 2 12.1 3g (9) 9 12.2 3g (1) 1 12.3 3g (1) 1 13.1 2j (2) 2 13.2 2j (4) 4 14 2a (2) 2 15 2d (3) 3 Total A 4 11 22 9 4 50 SECTION B 16.1 4m (2) 2 16.2 4m (1) 1 16.3 4n (1) 4o (2) 3 16.4 3n (9) 9 17 1a(2) 1b(2) 2aefik lmnop (10) 3g (1) 15 Total B 4 10 16 0 0 30 Total A+B 8 21 38 9 4 80