(A500U20-1) 7 11. The transfer speeds between the nodes of a network have the values shown in this diagram. A B C H G F E D 100 Kbps 100 Kbps 50 Kbps 100 Kbps 50 Kbps 50 Kbps 50 Kbps 250 Kbps 250 Kbps 250 Kbps 40 Kbps 50 Kbps 100 Kbps 200 Kbps 200 Kbps The cost for routing data between nodes is calculated by dividing 1Mbps by the transfer speed of the link. For example: Cost for the link A to B = = = 4 Data are transmitted between source and destination by the route which has the lowest total cost. (a) Copy the table below into your answer booklet. Complete the table to show the cost and transmission route that would be taken from source to destination. [4] Source Destination Cost Route A F E G (b) Calculate, to the nearest second and showing all of your working, the time required to transfer 220 KB (Kilo Bytes) of data from node G to node H. [4] 12. Partitioning of main memory is a responsibility of the operating system’s memory management function. Explain the need for partitioning of main memory, the different methods that can be used for partitioning and possible consequences associated with these methods. [9] END OF PAPER © WJEC CBAC Ltd. 1Mbps 250Kbps 1000 000 250 000