(a)Suggest reasons why RAMs traditionally have been organized as only one bit per chip whereas ROMs are usually organized with multiple bits per chip. [7]
(b)Consider a dynamic RAM that must be given a refresh cycle 64 times per ms. Each refresh operation requires 150 ns; a memory cycle requires 250 ns. What percentage of the memory's total operating time must be given to refreshes? [7]
(c)In the context of RAID, what is the distinction between parallel access and independent access? [6]
(20)
Q. 3
(a)The CPU in a router can process 2 million packets/sec. The load offered to it is 1.5 million packets/sec. If a route from source to destination contains 10 routers, how much time is spent being queued and serviced by the CPUs? [7]
(b)An IP datagram using the strict source routing option has to be fragmented. Do you think the option is copied into each fragment, or is it sufficient to just put it in the first fragment? Explain your answer. [7]
(c)Give two examples of computer applications for which connection-oriented service is appropriate and also give two examples for which connection-less service is best. [6]
(20)
Q. 4
(a)A 32-bit computer has two selector channels and one multiplexor channel. Each selector channel supports two magnetic disk and two magnetic tape units. The multiplexor channel has two line printers, two card readers, and ten VDTs terminals connected to it. Assume the following transfer rates. Disk drive 800 Kbytes/s Magnetic tape drive 200 Kbytes Line printer 6.6 Kbytes/s Card Reader 1.2 Kbytes/s VDT 1 Kbytes/s Estimate the maximum aggregate I/O transfer rate in this system. [12]
(b)Consider a program that access a single I/O device and compare un- buffered I/O to the use of a buffer. Show that the use of buffer can reduce the running time by at most a factor of two. [8]
(20)
Q. 5
(a)An I/O -bound program is one that, if run alone, would spend more time waiting for I/O than using the processor. A processor-bound program is the opposite. Suppose a short term scheduling algorithm favors those programs that have used little processor time in the recent past. Explain why this algorithm favors I/O bound programs and yet does not permanently deny processor time to processor- bound programs? [10]
(b)Suppose that instead of using 16-bits for the network part of a class B address originally, 20 bits had been used. How many class B networks would there have been? [5]
(c)What is the distinction between instruction-level parallelism and machine parallelism? [5]
(20)
SECTION–B
Q. 6
(a)Explain the following different SELECT statement search conditions with examples using any database schema of your choice: Compound Comparison Search Condition Range search condition (BETWEEN/NOT BETWEEN) Set membership search condition (IN/NOT IN) Pattern match search condition (LIKE/NOT LIKE) [12]
(b)Explain ACID property of a transaction [4]
(c)Explain Transitive dependency using any example. [4]
(20)
Q. 7
(a)A common measure of transmission for digital data is the baud rate, defined as the number of bits transmitted per second. Generally, transmission is accomplished in packets consisting of a start bit, a byte (8 bits) of information, and a stop bit. Using these facts, answer the following: How many minutes would it take to transmit a 1024 ×1024 image with 256 intensity levels using a 56k baud modem? What would the time be at 750K baud, are representative speed of a phone DSL (Digital subscriber line) connection? [10]
(b)What effect would setting to zero the lower-order bit planes have on the histogram of an image in general? [5]
(c)What would be the effect on the histogram if we set to zero the higher order bit planes instead? [5]
(20)
Q. 8
(a)How SEO improves your website traffic? Explain with proper reasons and coding examples. [8]
(b)Suppose your web team is going to make a contract with the customer and you need to estimate the cost of application development. What pricing factors you consider to estimate the cost? [8]
(c)Write the jQuery code to slide elements up and down. Use HTML, CSS, and jQuery [4]
The 2023 CSS Computer Science paper set by the Federal Public Service Commission. Question wording only; questions marked “Not yet checked” have not been compared with the official paper yet. Open the official paper beside the questions to check any of them.
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