JYSS 2018 P1 Solution

Answers 1 (a) RING Network - Any TWO from: [textbook] Advantages Disadvantages • Can operate over larger distances and handle more data • If a computer or cable in the network fails, the entire network may fail as the data cannot be passed on • Data packets that are sent between two computers will pass through intermediate computers, hence a central server is not required to manage the network • Adding a new computer to the ring network would mean that the whole communication ring needs to be temporarily interrupted -shared resources -less efficient than star because it needs to travel through all other work stations first to get to destination work station -a faulty connection between two stations can cause network failure -it is difficult to add a new station/device as it has to come between 2 existing stations -this type works well during heavy loading -it is possible to create large networks using this topology (b) STAR Network - Any TWO from: [textbook] Advantages Disadvantages • The load on each section of cabling is reduced as each computer uses a separate cable from the rest • Uses more cabling than other topologies and hence costs more • If a fault occurs at a computer or cable, it is easy to isolate the fault and do a replacement without affecting the rest of the network • If the central network device fails, the entire network fails -shared resources -cable failure isolates/affects only the work station where cable failed -if one station/connection fails the other devices are not affected -if the central hub breaks down, the whole network fails -it is easier to identify faults using this type of topology -it is easy to expand this type of network

2 2 1 mark for each correct tick 3 Description It is more difficult to debug the code since one error can produce many other associated errors. The speed of execution of program loops is slower. Compiler It produces fast, executable code that runs directly on the processor. Interpreter It is easier to debug the code since an error is displayed as soon as it is found. Statement True (/) False (/) Firewalls can monitor incoming and outgoing traffic. ü Firewalls cannot block access to a certain website. ü Firewalls can be software and hardware. ü Firewalls can act as intermediary servers. ü Firewalls can block unauthorised traffic. ü

3 4E Computing P1 2018 Prelim [Turn over 4 (a) (i) – value of count starts at 1 so only 999 iterations – value of count reaches 1000, but before 1000th input (ii) – line 1 should read count = 0 – line 5 should read count = 1001 (or count >1000) – change to appropriate loop structure [2] (b) (i) – normal/valid (test data) – any value in given range (1 to 12) e.g. 4 (ii) – abnormal/invalid (test data) – any value which is outside the range/any value not acceptable – i.e. letters, negative numbers, values > 12 e.g. adfrk, -20, 36 (iii) – extreme/boun