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Redesign the configuration of Problem 8-12 using the Clos criteria. Problem 8-12 We need a three-stage space-division switch with N = 100. We use 10 crossbars at the first and third stages and 4... Repeat Problem P13-8 for a Gigabit Ethernet LAN. Problem P13-8 In a Standard Ethernet LAN, the average size of a frame is 1000 bytes. If a noise of 2 ms occurs on the LAN, how many frames are... What are the two major services provided by telephone companies in the United States? Repeat Problem P14-7 using ADSL implementations (consider the minimum rates). Problem P14-7 Calculate the minimum time required to download one million bytes of information using a 56K modem. A stream of data is being carried by STS-1 frames. If the data rate of the stream is 49.530 Mbps, how many frames per second should leave one empty byte after the H3 byte? Compare the medium of a wired LAN with that of a wireless LAN in todays communication environment. In Figure 17.5, do we have a loop problem if we change each hub in the LANs to a link-layer switch? Figure 17.5 Figure 17.5 Loop problem in a learning switch a. Station A sends a frame to station D... Does each port of the switch in Figure 17.3 need a link-layer address? Explain. Figure 17.3 Figure 17.3 Link-layer switch Switch Switching table Address Port 4 71:2B:13:45:61:41 71:2B:13:45:61:42 2... List four types of delays in a packet-switched network. An organization is granted the block 130.56.0.0/16. The administrator wants to create 1024 subnets. a. Find the number of addresses in each subnet. b. Find the subnet prefix. c. Find the first and... Assume router R2 in Figure 18.35 receives a packet with destination address 140.24.7.42. How is the packet routed to its final destination? Figure 18.35 Figure 18.35 Longest mask matching... A packet has arrived in which the offset value is 300 and the payload size is 100 bytes. What are the number of the first byte and the last byte? Redraw Figure 19.18 for the case where the mobile host acts as a foreign agent. Figure 19.18 Data transfer Home network Mobile host Remote network original home Remote host Home ag ent Internet... In Figure 19.4, a. Show how wrapped sum can be calculated from the sum using modular arithmetic. b. Show how checksum can be calculated from the wrapped sum using modular arithmetic. Figure 19.4... Can you explain why BGP uses the services of TCP instead of UDP? Create the shortest path tree and the forwarding table for node B in Figure 20.8. Figure 20.8 Example of a link-state database A B C DE F G A02 00 B| 20 5 00 3 00 4 00 A C00 D 3 0 3 4 3. o0 0 4 00 4... In a very small AS using OSPF, is it more efficient to use only one single area (backbone) or several areas? Distinguish between multicasting and multiple unicasting. The AS number in an organization is 24101. Find the range of multicast addresses that the organization can use in the GLOP block. Explain why broadcasting the first or the first few messages is not important in PIM-DM, but it is important in PIM-SM? Distinguish between compatible and mapped addresses and explain their applications. Assume you need to write and test a client-server application program on two hosts you have at home. a. What is the range of port numbers you would choose for the client program? b. What is the range... Assume that our network may corrupt packets, but it never loses or duplicates a packet. We are also concerned about flow control. We do not want the sender to overwhelm the receiver with packets.... A client residing on a host with IP address 122.45.12.7 sends a message to the corresponding server residing on a host with IP address 200.112.45.90. If the well-known port is 161 and the ephemeral... What can you say about each of the following TCP segments, in which the value of the control field is: a. 000000 b. 000001 c. 010001 d. 000100 e. 000010 f. 010010 In a TCP connection, the initial sequence number at the client site is 2171. The client opens the connection, sends three segments, the second of which carries 1000 bytes of data, and closes the... The maximum window size of the TCP was originally designed to be 64 KB (which means 64 1024 = 65,536 or actually 65,535). Can you think of a reason for this? In TCP, can the sender window be smaller, larger, or the same size as the receiver window? Assume a TCP server is expecting to receive byte 6001. It receives a segment with the sequence number 6001 that carries 2000 bytes. If the server has bytes 4001 to 5000 to send, what should the... If originally RTT S = 14 ms and is set to 0.2, calculate the new RTT S after the following events (times are relative to event 1): Event 1: 00 ms Segment 1 was sent. Event 2: 06 ms Segment 2 was... The following is a dump of an SCTP general header in hexadecimal format. 04320017 00000001 00000000 a. What is the source port number? b. What is the destination port number? c. What is the value of... An SCTP client opens an association using an initial tag of 806, an initial TSN of 14534, and a window size of 20,000. The server responds with an initial tag of 2000, an initial TSN of 670, and a... Write the relational algebra formula to apply an INTERSECT relational operator to the tables shown in Figure Q3.13. Figure Q3.13: Database name: Ch03_VendingCo Table name: MACHINE MACHINE_PRODUCT... Based on the following query: SELECT P_CODE, SUM(LINE_UNITS) FROM LINE GROUP BY P_CODE HAVING SUM(LINE_UNITS) > (SELECT MAX(LINE_UNITS) FROM LINE); Should you create an index? If so, what would the... Based on the following query: SELECT CUS_CODE, MAX(LINE_UNITS*LINE_PRICE) FROM CUSTOMER NATURAL JOIN INVOICE NATURAL JOIN LINE WHERE CUS_AREACODE = 615 GROUP BY CUS_CODE; How would you rewrite the... Use the fact database and patron collection created in the text for use with MongoDB. Write a query to retrieve the documents of patrons that are faculty and checked out book 5235, or that are... Change the STORE_REPS table so that only a Y or N can be entered in the Comm column. Which command can you use to change the existing data in a table? Modify the zip code on order 1017 to 33222. Execute a command that undoes the previous deletion. Create a sequence for populating the Customer# column of the CUSTOMERS table. When setting the start and increment values, keep in mind that data already exists in this table. The options should be... Convert the following table to an equivalent collection of tables that are in third normal form. This table contains information about patients of a dentist. Each patient belongs to a household.... What happens if you revoke an object privilege that was granted with the WITH GRANT OPTION? What if the privilege is removed from a user who had granted the same object privilege to three other users? Add a new customer row by using the sequence created in Question 1. The only data currently available for the customer is as follows: last name = Shoulders, first name = Frank, and zip = 23567. Data... Create a sequence that generates integers starting with the value 5. Each value should be three less than the previous value generated. The lowest possible value should be 0, and the sequence... The owner of Colonial Adventure Tours knows the importance of the SQL language in database management. He realizes that he can use SQL to perform the same functions that you performed with queries in... In the following exercises, you will use the data in the Solmaris Condominium Group database shown in Figures 1-21 through 1-25 in Chapter 1. (If you use a computer to complete these exercises, use a... In the following exercises, you will use the data in the TAL Distributors database shown in Figure 2-1 in Chapter 2. (If you use a computer to complete these exercises, use a copy of the original TAL... The following exercises are based on the TAL Distributors database as designed in Example 1 in this chapter. In each exercise, represent your answer in DBDL and with a diagram. You may use any of the... Which orders shipped after April 1, 2009? List each order number and the date it shipped. Which books arent in the Fitness category? List each book title and category. Which customers live in Georgia or New Jersey? Put the results in ascending order by last name. List each customers customer number, last name, and state. Write this query in two different ways. List all authors whose last name contains the letter pattern IN. Put the results in order of last name, then first name. List each authors last name and first name. Display the book title and category for all books in the Children and Cooking categories. Create three different queries to accomplish this task: a) A search pattern operation, b) A logical operator,... For the following exercises, you will address problems and answer questions from the Solmaris Condominium Group staff. You do not use the Solmaris database for any of these exercises. 1. The log... Determine which orders havent yet shipped and the name of the customer who placed the order. Sort the results by the date on which the order was placed. Which of the following queries contains a non-equality join? a. SELECT title, authorid FROM books, bookauthor WHERE books.isbn = bookauthor.isbn AND retail > 20; b. SELECT title, name FROM books JOIN... The following SQL statement contains which type of join? SELECT title, order#, quantity FROM books FULL JOIN orderitems ON books.isbn = orderitems.isbn; a. Equality b. Self-join c. Non-equality d.... Given the following query: SELECT zip, order# FROM customers NATURAL JOIN orders; Which of the following queries is equivalent? a. SELECT zip, order# FROM customers JOIN orders WHERE... Which of the following is a valid SQL statement? a. SELECT SYSDATE; b. SELECT UPPER (Hello) FROM dual; c. SELECT TO_CHAR (SYSDATE, 'Month DD, YYYY') FROM dual; d. All of the above e. None of the above Create a list of all book titles and costs. Precede each books cost with asterisks so that the width of the displayed Cost field is 12. Determine the length of data stored in the ISBN field of the BOOKS table. Make sure each different length value is displayed only once (not once for each book). Using todays date, determine the age (in months) of each book that JustLee sells. Make sure only whole months are displayed; ignore any portions of months. Display the book title, publication date,... Which of the following lists only the last four digits of the contact persons phone number at American Publishing? a. SELECT EXTRACT (phone, -4, 1) FROM publisher WHERE name = 'AMERICAN PUBLISHING';... Produce a list of each customer number and the third and fourth digits of his or her zip code. The query should also display the position of the first occurrence of a 3 in the customer number, if it... Determine how many books are in the Cooking category. Display the number of books with a retail price of more than $30.00. Display the most recent publication date of all books sold by JustLee Books. Which of the following SQL statements lists all books written by the author of The Wok Way to Cook? a. SELECT title FROM books WHERE isbn IN (SELECT isbn FROM bookauthor HAVING authorid IN 'THE WOK... Determine which orders had a higher total amount due than order 1008. Determine which books were published by the publisher of The Wok Way to Cook. Find the probability when (a) k = 2 and = 0.01 for Poisson distribution. (b) p = 0.01 and k = 2 for geometric distribution. (c) Repeat (b) when binomial distribution is used and n = 10. What is the diversity reception? How can it be used to combat multipath? a. If both UTP and optical fiber can be used for a particular physical link, which should I choose? Why? b. If both OM3 fiber and OM4 fiber can be used for a particular physical link, which should I... In SCTP, the state of a receiver is as follows: a. The receiving queue has chunks 1 to 8, 11 to 14, and 16 to 20. b. There are 1800 bytes of space in the queue. c. The value of lastAck is 4. d. No... a. Convert the base 4 number 13023031 4 directly to hexadecimal. Check your result by converting both the original number and your answer to decimal. b. Convert the hexadecimal number 9B62 16... It is common to represent network connections in IT systems as a cloud. (See, for example, Figures 2.6, 2.7, 2.8, and 2.9). The cloud is obviously an abstraction as we defined abstraction in this... A high-quality photographic image requires 3 bytes per pixel to produce sixteen million shades of color. a. How large a video memory is required to store a 640 480 image during display? A 1600 900... The average latency on a disk with 2200 sectors is found experimentally to be 110 msec. a. What is the rotating speed of the disk? b. What is the transfer time for one sector? A multiplattered hard disk is divided into 1100 sectors and 40,000 cylinders. There are six platter surfaces. Each block holds 512 bytes. The disk is rotating at a rate of 4800 rpm. The disk has an... Suppose you wish to send a block of data to a tape drive for storage using DMA. What information must be sent to the tape controller before the DMA transfer can take place? Suppose that a CPU always executes the two instructions following a branch instruction, regardless of whether the branch is taken or not. Explain how this can eliminate most of the delay resulting... Most of the registers in the machine have two-way copy capability; that is, you can copy to them from another register, and you can copy from them to another register. The MAR, on the other hand, is... One large modern computer has a 48-bit memory address register. How much memory can this computer address? Write a Little Man program that adds a column of input values and produces the sum as output. The first input value will contain the number of values that follow as input to be added. Using the same format found in Exercise 5.19, add and multiply the following floating point numbers. Present your answers in both floating point and sign-and-magnitude formats. 3DEC0000 16 C24C0000... a. Consider a CPU with two parallel integer execution units. An addition instruction requires 2 clock pulses to complete execution, and a multiplication requires 15 clock pulses. Now assume the... Assume object x has only one table with two columns. What is the identifier for each column? The Fourier series coefficients of a periodic signal x(t), with fundamental frequency Ω 0 = Ï/4 are X 1 = X 1 =j, X 5 = X 5 = 2 and the rest are zero. Suppose x(t) is the input to a... Suppose you want to design a dc-source using a half-wave rectified signal x(t) and an ideal filter. Let x(t) be periodic, T 0 = 2, and with a period (a) Find the Fourier transform X(Ω) of... When you receive a set of tables, what steps should you take to assess their structure and content? Consider a causal LTI system with impulse response h[n], and input x[n] = x 1 [n] x 1 [n 2] + x 1 [n 4] where x 1 [n] = u[n] u[n 2]. The impulse response of the system is h[n] = u[n] u[n 2] (a) Use... The receiver of an AM system consists of a band-pass filter, a demodula-tor, and a low-pass filter. The received signal is r(t) = m(t)cos(40000 t) + q(t) where m(t) is a desired voice signal with... Describe two ways to represent a 1:1 recursive relationship. Give an example other than one in this chapter. Why should one be wary of general-purpose remarks columns? a. In MPLS, is selecting the best interface for each packet at each router done when the packet enters the network or before? 17a.) In MPLS, the router interface to send the packet back out will be... What is the difference between an information system and a computer application? Prove each of the following statements, or give a counter example: a. Breadth-first search is a special case of uniform-cost search. b. Depth-first search is a special case of best-first tree search.... Suppose that the performance measure is concerned with just the first T time steps of the environment and ignores everything thereafter. Show that a rational agents action may depend not just on the... Surely animals cannot be intelligentthey can do only what their genes tell them. Is the latter statement true, and does it imply the former?
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