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The ssthresh value for a Reno TCP station is set to 8 MSS. The station is now in the slow-start state with cwnd = 5 MSS and ssthresh = 8 MSS. Show the values of cwnd, ssthresh, and the current and... In Figure 25.10 in the text, how does the server know that a client has requested a service? Figure 25.10 Sockets used in TCP communication Server O Connection establishment Client 1 Data transfer... Assume we add a new protocol to the application layer. What changes do we need to make to other layers? Write a method in Java to find the last address in the block when one of the addresses in the block is given as a string representing a CIDR notation. Can a program written to use the services of UDP be run on a computer that has installed TCP as the only transport-layer protocol? Explain. Write a method in Java to convert a 32-bit integer to a string representing an IP address in the form x.y.z.t. A new application is to be designed using the client-server paradigm. If only small messages need to be exchanged between the client and the server without concern for message loss or corruption,... Write a program to make the TCP client program in Table 25.4 more generic to be able to send any request created by the program. Table 25.4 Echo client program using TCP 1 / TCP echo client program 2... Write a method in Java to change an integer representing a prefix to an unsigned 32-bit integer representing the numeric mask. Explain how a client process finds the IP address and the port number to be inserted in a remote socket address. Write a method in Java to change an unsigned 32-bit integer representing a mask to an integer representing a prefix (/n). Assume we design a new client-server application program that requires persistent connection. Can we use UDP as the underlying transport-layer protocol for this new application? In FTP, assume a client with user name John needs to store a video clip called video2 on the directory /top/videos/general on the server. Show the commands and responses exchanged between the client... Assume we need to download an audio using FTP. What file type should we specify in our command? Encode the following message in base64: 01010111 00001111 11110000 During the weekend, Alice often needs to access files stored on her office desktop from her home laptop. Last week, she installed a copy of the FTP server process on her desktop at her office and a... Assume there is a server with the domain name www.common.com. a. Show an HTTP request that needs to retrieve the document/usr/users/doc. The client accepts MIME version 1, GIF or JPEG images, but the... In Figure 25.18, how does the client create the input and output streams to communicate with the server? Figure 25.18 Figure 25.18 Design of the TCP client Client application program Create request... We say that in network programming a socket should be at least bound to a local socket address. The first constructor of the DatagramSocket class (see Table 25.10) has no parameters. Can you explain... It costs $1 billion to build a new fabrication facility. You will be selling a range of chips from that factory, and you need to decide how much capacity to dedicate to each chip. Your Woods chip... Create the basic Crows Foot ERD for Tiny College. Is it possible for a book to appear in the BOOK table without appearing in the PRODUCT table? Why or why not? What is the difference between the COUNT aggregate function and the SUM aggregate function? Describe the three most common problems with concurrent transaction execution. Explain how concurrency control can be used to avoid those problems. Based on the following query: SELECT EMP_LNAME, EMP_FNAME, EMP_DOB, YEAR(EMP_DOB) AS YEAR FROM EMPLOYEE WHERE YEAR(EMP_DOB) = 1966; What is the likely data sparsity of the EMP_DOB column? Luxury-Oriented Scenic Tours (LOST) provides guided tours to groups of visitors to the Washington D.C. area. In recent years, LOST has grown quickly and is having difficulty keeping up with all of... Based on the ER model shown in Figure P11.7 and on the query shown after the figure. Figure P11.7: Given the following query SELECT P_CODE, P_PRICE FROM PRODUCT WHERE P_PRICE >= (SELECT AVG(P_PRICE)... Based on the ER model shown in Figure P11.7 and on the query shown after the figure. Figure P11.7: Should you create an index? Why or why not? INVOICE CUSTOMER LINE PK Cus CODE PK INV_NUMBER PK,FK1... Which of the following is not a valid SELECT statement? a. SELECT lastname, firstname FROM customers; b. SELECT * FROM orders; c. Select FirstName NAME from CUSTOMERS; d. SELECT lastname Last Name... Explain how you would determine how much profit was generated from orders placed in April 2009. Figure 1-5: ORDERS Order# Customer# Orderdate Shipdate Shipstreet Shipcity Shipstate Shipzip Shipcost... Add two columns to the EMPLOYEES table. One column, named EmpDate, contains the date of employment for each employee, and its default value should be the system date. The second column, named... Create a new table containing these four columns from the existing BOOKS table: ISBN, Cost, Retail, and Category. The name of the ISBN column should be ID, and the other columns should keep their... Mark the Category column of the BOOK_PRICING table as unused. Verify that the column is no longer available. Truncate the BOOK_PRICING table, and then verify that the table still exists but no longer contains any data. Which of the following is a valid SQL statement? a. CREATE TABLE tablel (col1 NUMBER PRIMARY KEY, col2 VARCHAR2 (20) PRIMARY KEY, col3 DATE DEFAULT SYSDATE, col4 VARCHAR2 (2)); b. CREATE TABLE tablel... Which command should you use to copy data from one table and have it added to an existing table? What two methods can be used to activate a columns DEFAULT option in an INSERT command? Which of the following is a correct statement? a. A commit is issued implicitly when a user exits SQL Developer or SQL*Plus. b. A commit is issued implicitly when a DDL command is executed. c. A... Execute the script and set the following values: isbn = 1059831198 and cost = $20.00. Which of the following generates a series of integers that can be stored in a database? a. A number generator b. A view c. A sequence d. An index e. A synonym Which syntax is correct for removing a public synonym? a. DROP SYNONYM synonymname; b. DELETE PUBLIC SYNONYM synonymname; c. DROP PUBLIC SYNONYM synonymname; d. DELETE SYNONYM synonymname; Which of the following commands can you use to modify an index? a. ALTER SESSION b. ALTER TABLE c. MODIFY INDEX d. ALTER INDEX e. None of the above Which of the following is a valid SQL statement? a. INSERT INTO publisher VALUES (pubsequence.nextvalue, 'HAPPY PRINTING', 'LAZY LARRY', NULL); b. CREATE INDEX a_new_index ON (firstcolumn*.02); c.... Which of the following statements is true? a. A gap can appear in a sequence created with the NOCACHE option if the system crashes before a user can commit a transaction. b. Any unassigned sequence... The owner of Colonial Adventure Tours knows that being able to run queries is one of the most important benefits of using a DBMS. In the following exercises, you will use the data in the Colonial... 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... Issue a SELECT statement that displays NEXTVAL for MY_FIRST_SEQ three times. Because the value isnt being placed in a table, use the DUAL table in the FROM clause of the SELECT statement. What causes... Which of the following is an object privilege? a. CREATE SESSION b. DROP USER c. INSERT ANY TABLE d. UPDATE Using an account with the required privileges, create a role named CUSTOMERREP that allows inserting new rows in the ORDERS and ORDERITEMS tables and deleting rows from these tables. The City Jail organization is preparing to deploy the new database to four departments. The departments and associated duties for the database are described in the following chart: Based on the... List all customers who were referred to the bookstore by another customer. List each customers last name and the number of the customer who made the referral. Answer each of the following questions using the TAL Distributors data shown in Figure 1-5. No computer work is required. 1. List the names of all customers that have a credit limit that is less than... The management of Colonial Adventure Tours asks you to research improvements it might make to its database processing. To help management, they would like you to complete the following exercises. You... Which of the following returns a list of all customers names sorted in descending order by city within state? a. SELECT name FROM customers ORDER BY desc state, city; b. SELECT firstname, lastname... Display a list ofall books in the BOOKS table. If a book has been ordered by a customer, also list the corresponding order number and the state in which the customer resides. Which of the following queries is valid? a. SELECT b.title, b.retail, o.quantity FROM books b NATURAL JOIN orders od NATURAL JOIN orderitems o WHERE od.order# = 1005; b. SELECT b.title, b.retail,... Which of the following functions can be used to extract a portion of a character string? a. EXTRACT b. TRUNC c. SUBSTR d. INITCAP Which line in the following SQL statement raises an error? 1. SELECT name, title 2. FROM books NATURAL JOIN publisher 3. WHERE category = 'FITNESS' 4. OR 5. books.pubid = 4; a. line 1 b. line 2 c.... Which of the following is not a valid format argument for displaying the current time? a. 'HH:MM:SS' b. 'HH24:SS' c. 'HH12:MI:SS' d. All of the above are valid. Which of the following functions can be used to determine how many months a book has been available? a. MONTH b. MON c. MONTH_BETWEEN d. None of the above Create a list of all customer numbers along with text indicating whether the customer has been referred by another customer. Display the text NOT REFERRED if the customer wasnt referred to JustLee... Display a list of all book titles and the percentage of markup for each book. The percentage of markup should be displayed as a whole number (that is, multiplied by 100) with no decimal position,... The following list reflects the current data requests from city managers. Provide the SQL statements that satisfy the requests. For each request, include one solution using the traditional method and... Which of the following SQL statements produces Hello World as the output? a. SELECT "Hello World" FROM dual; b. SELECT INITCAP ('HELLO WORLD') FROM dual; c. SELECT LOWER ('HELLO WORLD') FROM dual; d.... Which of the following functions can be used to substitute a value for a NULL value? a. NVL b. TRUNC c. NVL2 d. SUBSTR e. Both a and d f. Both a and c Which of the following displays the order date for order 1000 as 03/31? a. SELECT TO_CHAR (orderdate, 'MM/DD') FROM orders WHERE order# = 1000; b. SELECT TO_CHAR (orderdate, 'Mth/DD') FROM orders... Which of the following statements is true? a. The MIN function can be used only with numeric data. b. The MAX function can be used only with date values. c. The AVG function can be used only with... Which of the following SQL statements is not valid? a. SELECT TO_CHAR (orderdate, '99/9999') FROM orders; b. SELECT INITCAP (firstname), UPPER (lastname) FROM customers; c. SELECT cost, retail,... Which of the following SELECT statements returns 30 as the result? a. SELECT ROUND (24.37, 2) FROM dual; b. SELECT TRUNC (29.99, 2) FROM dual; c. SELECT ROUND (29.01, -1) FROM dual; d. SELECT TRUNC... Use the following SELECT statement to answer. 1 SELECT customer#, COUNT(*) 2 FROM customers JOIN orders USING (customer#) 3 WHERE orderdate > '02-APR-09' 4 GROUP BY customer# 5 HAVING COUNT(*) > 2;... List the book title and retail price for all books with a retail price lower than the average retail price of all books sold by JustLee Books. Determine which books cost less than the average cost of other books in the same category. Create a view that lists the ISBN and title for each book in inventory along with the name and phone number of the person to contact if the book needs to be reordered. Name the view REORDERINFO. Delete the record in the REORDERINFO view containing your name. (If you werent able to perform #6 successfully, delete one of the contacts already listed in the table.) Was an error message displayed... Issue a rollback command to undo any changes made with the preceding DML operations. The City Jail Technologies Department is constructing an application to allow users in the Crime Analysis Unit to query data more easily. This system requires creating a number of views, described in... State whether each of the following is true or false. If false, explain why. a) Software objects model both abstract and real-world things. b) The most popular database model is the relational... Some people want to eliminate sexism in all forms of communication. Youve been asked to create a program that can process a paragraph of text and replace gender-specific words with gender-neutral... Write statements to accomplish each of the following tasks: a) Declare variables c, thisIsAVariable, q76354 and number to be of type int. b) Prompt the user to enter an integer. c) Input an integer... What does a small delay spread indicate about the characteristics of a fading channel? If the delay spread is 1 microsecond, will two different frequencies that are 5 MHz apart, experience correlated... A BS has a 900 MHz transmitter and a vehicle is moving at the speed of 50 mph. Compute the received carrier frequency if the vehicle is moving (a) Directly toward the BS. (b) Directly away from the... Implement the bubble sortanother simple, yet inefficient, sorting technique. Its called bubble sort or sinking sort because smaller values gradually bubble their way to the top of the array (i.e.,... A random digit generator on a computer is activated three times consecutively to simulate a random three-digit number. (a) How many random three-digit numbers are possible? (b) How many numbers will... What causes the inter-symbol interference and how can you reduce the intersymbol interference in the wireless communication system? Is the AP at a caf or an executive mansion similar to the one used in an institution or home? a. Compute the minimum number of TCP segments required to open a connection, send an HTTP request and response message, and close the connection. Justify this number by creating a table showing each... a. If the backup line in Figure 3-14 were to connect Seattle and Dublin instead of Honolulu and Ogden, list the path that traffic would take between Honolulu and Dublin if the line between Seattle... a. What is a local area network (LAN)? 1a.) A local area network operates . a. On a customer premises b. Between customer premises c. Both A and B d. Neither A nor B a. What is the security benefit of Ethernet VLANs? 23a.) Which of the following provides security in Ethernet? a. RSTP b. SNMP c. VLANs d. All of the above b. In Figure 5-28, to which hosts can Host... a. What type of attack does 802.1A E protect against? 25a.) To prevent an unauthorized user from sending supervisory commands to switches, companies use _____. a. 802.1X b. SNMP c. VLANs d. 802.1AE Why might a company decided to use 80 MHz channels in 802.11ac instead of 160 MHz channels? a. What is the definition of hacking? 9a1.) Hacking is defined as using a computer resource without authorization or in excess of authorization. a. True b. False 9a2.) Which of the following meets... a. _______ switches connect users to the network. 3a.) What type of switch connects users to the network? a. User switches b. Core switches c. Access switches d. Work group switches b. _______... A client PC has two simultaneous connections to the same web-server application program on a web-server. (Yes, this is possible, and in fact, it is rather common.) What will be different between the... Write, test, validate, and debug (if necessary) markup documents and JavaScript files for the following: Modify the document described in Exercise 6.1 to add four buttons labeled, respectively,... a. What is a mode? 10a.) When the light energies of two pulses arrive at the far end at overlapping times, this is ______. a. Multi mode transmission b. Modal bandwidth c. Modal dispersion d. Modal... a. Compare relative cost and maximum propagation distance for multimode and single-mode fiber. 14a.) Fiber that has a core diameter of 8.3 microns is _______. a. Multimode fiber b. Single-mode fiber... a. What security threat is 802.1X designed to protect against? 24a.) To prevent anyone from simply walking up to a corporate switch and plugging their computer into its Ethernet port, companies can... a. Before the attack, where does the ARP cache tell the victim to send a frame carrying a packet to the router? 26a.) The ARP cache gives the _______ of a router the host will send a packet to. a. IP... a. What is a transceiver? b. Is wireless radio transmission usually described in terms of wavelength or frequency? 5b.) Wireless radio transmission speed is usually measured in terms of _______. a....
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