Enhanced Discovering Computers 2017 (Shelly Cashman Series) (MindTap Course List)
1st Edition
ISBN: 9781305657458
Author: Misty E. Vermaat, Susan L. Sebok, Steven M. Freund, Mark Frydenberg, Jennifer T. Campbell
Publisher: Cengage Learning
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Chapter 4, Problem 36SG
Explanation of Solution
Functions of personal firewall, hardware firewall, antivirus
Personal firewall:
- It is a network security tool and its function is to find and protect computers and all its information from unauthorized intrusions.
- It regularly monitors all the communication happens to and from the computer.
- If any intrusions occur, then the personal firewall informs the user by giving a message.
- Example: If the user downloads any software or any file from the Internet, and if that file contains virus; then the firewall instructs the user that the file contains virus and warns to discard that file.
- Example of personal firewall is Comodo firewall.
Hardware firewall:
- It is a device and its function is to stop the network interruptions before they try to affect the computers.
- Routers also acts as a hardware firewall.
- Hardware firewall uses packet filtering method in order to examine the header of the packet that contains source and destination.
- Example of hardware firewall is Cisco SA 500...
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Students have asked these similar questions
Activity No.
Activity
Time (weeks)
Immediate Predecessors
1
Requirements collection
3
2
Requirements structuring
4
1
3
Process analysis
3
2
4
Data analysis
3
2
5
Logical design
50
3,4
6
Physical design
5
5
7
Implementation
6
6
c. Using the information from part b, prepare a network diagram. Identify the critical path.
Given the following Extended-BNF grammar of the basic mathematical expressions:
Show the derivation steps for the expression: ( 2 + 3 ) * 6 – 20 / ( 3 + 1 )
Draw the parsing tree of this expression.
SEE IMAGE
Whentheuserenters!!,themostrecentcommandinthehistoryisexecuted.In the example above, if the user entered the command:
Osh> !!
The ‘ls -l’ command should be executed and echoed on user’s screen. The command should also be placed in the history buffer as the next command.
Whentheuserentersasingle!followedbyanintegerN,theNthcommandin the history is executed. In the example above, if the user entered the command:
Osh> ! 3
The ‘ps’ command should be executed and echoed on the user’s screen. The command should also be placed in the history buffer as the next command.
Error handling:
The program should also manage basic error handling. For example, if there are no commands in the history, entering !! should result in a message “No commands in history.” Also, if there is no command corresponding to the number entered with the single !, the program should output "No such command in history."
Chapter 4 Solutions
Enhanced Discovering Computers 2017 (Shelly Cashman Series) (MindTap Course List)
Ch. 4 - Prob. 1SGCh. 4 - Prob. 2SGCh. 4 - Prob. 3SGCh. 4 - Prob. 4SGCh. 4 - _____ software performs functions specific to a...Ch. 4 - Prob. 6SGCh. 4 - List any restrictions for shareware, freeware,...Ch. 4 - Prob. 8SGCh. 4 - Prob. 9SGCh. 4 - Prob. 10SG
Ch. 4 - Prob. 11SGCh. 4 - Prob. 12SGCh. 4 - Prob. 13SGCh. 4 - Prob. 14SGCh. 4 - Prob. 15SGCh. 4 - Prob. 16SGCh. 4 - Prob. 17SGCh. 4 - Prob. 18SGCh. 4 - Prob. 19SGCh. 4 - Prob. 20SGCh. 4 - Prob. 21SGCh. 4 - Prob. 22SGCh. 4 - Prob. 23SGCh. 4 - Prob. 24SGCh. 4 - Prob. 25SGCh. 4 - Prob. 26SGCh. 4 - Prob. 27SGCh. 4 - Prob. 28SGCh. 4 - Prob. 29SGCh. 4 - Prob. 30SGCh. 4 - Prob. 31SGCh. 4 - Prob. 32SGCh. 4 - Prob. 34SGCh. 4 - Prob. 35SGCh. 4 - Prob. 36SGCh. 4 - Prob. 37SGCh. 4 - Prob. 38SGCh. 4 - Prob. 39SGCh. 4 - Prob. 40SGCh. 4 - Prob. 41SGCh. 4 - Prob. 42SGCh. 4 - Prob. 43SGCh. 4 - Prob. 44SGCh. 4 - Prob. 45SGCh. 4 - Prob. 46SGCh. 4 - Prob. 47SGCh. 4 - Prob. 48SGCh. 4 - Prob. 49SGCh. 4 - Prob. 1TFCh. 4 - Prob. 2TFCh. 4 - Prob. 3TFCh. 4 - Prob. 4TFCh. 4 - Prob. 5TFCh. 4 - Prob. 6TFCh. 4 - Prob. 7TFCh. 4 - Prob. 8TFCh. 4 - Prob. 9TFCh. 4 - Prob. 10TFCh. 4 - Prob. 11TFCh. 4 - Prob. 12TFCh. 4 - Prob. 1MCCh. 4 - Prob. 2MCCh. 4 - Prob. 3MCCh. 4 - Prob. 4MCCh. 4 - Prob. 5MCCh. 4 - Prob. 6MCCh. 4 - Prob. 7MCCh. 4 - Prob. 8MCCh. 4 - Prob. 1MCh. 4 - Prob. 2MCh. 4 - Prob. 3MCh. 4 - Prob. 4MCh. 4 - Prob. 5MCh. 4 - Prob. 6MCh. 4 - Prob. 7MCh. 4 - Prob. 8MCh. 4 - Prob. 9MCh. 4 - Prob. 10MCh. 4 - Prob. 2CTCh. 4 - Prob. 3CTCh. 4 - Prob. 4CTCh. 4 - Prob. 5CTCh. 4 - Prob. 6CTCh. 4 - Prob. 7CTCh. 4 - Prob. 8CTCh. 4 - Prob. 9CTCh. 4 - Prob. 10CTCh. 4 - Prob. 11CTCh. 4 - Prob. 12CTCh. 4 - Prob. 13CTCh. 4 - Prob. 14CTCh. 4 - Prob. 15CTCh. 4 - Prob. 16CTCh. 4 - Prob. 17CTCh. 4 - Prob. 18CTCh. 4 - Prob. 19CTCh. 4 - Prob. 20CTCh. 4 - Prob. 21CTCh. 4 - Prob. 22CTCh. 4 - Prob. 23CTCh. 4 - Prob. 24CTCh. 4 - Prob. 25CTCh. 4 - Prob. 26CTCh. 4 - Prob. 27CTCh. 4 - Prob. 28CTCh. 4 - Prob. 29CTCh. 4 - Prob. 30CTCh. 4 - Prob. 1PSCh. 4 - Prob. 2PSCh. 4 - Prob. 3PSCh. 4 - Prob. 4PSCh. 4 - Prob. 5PSCh. 4 - Prob. 6PSCh. 4 - Prob. 7PSCh. 4 - Prob. 8PSCh. 4 - Prob. 9PSCh. 4 - Prob. 10PSCh. 4 - Prob. 1.1ECh. 4 - Prob. 1.2ECh. 4 - Prob. 1.3ECh. 4 - Prob. 2.1ECh. 4 - Prob. 2.2ECh. 4 - Prob. 2.3ECh. 4 - Prob. 3.1ECh. 4 - Prob. 3.2ECh. 4 - Prob. 3.3ECh. 4 - Prob. 4.1ECh. 4 - Prob. 4.2ECh. 4 - Prob. 4.3ECh. 4 - Prob. 5.1ECh. 4 - Prob. 5.2ECh. 4 - Prob. 5.3ECh. 4 - Prob. 1IRCh. 4 - Prob. 2IRCh. 4 - Prob. 4IRCh. 4 - Prob. 2CTQ
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