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Additional Lab Assignment 1

The acronym for VLSI is Very large Scale Integration.
Input devices, output devices,memory devices,
processor devices and control devices.
High-level languages such a Fortran and Cobol.
logical operator "AND" works like multiplication operation
ALU consist of three components Registers, the ALU circuits, and the BUS.
The third generation computers operating systems were designed to
enable the devices to run different applications simultaneously.
First generation vacuum tubes and magnetic drums,second generation vacuum
tubes were changed to transistors,third generation used integrated circuits,
fourth generation using LSI, VLSI, ULSI and fifth generation based on artificial
intelligence.The fifth generation computer are based on artificial Intelligence.
logical operator "AND" gives an output of 0 when a minimum 1 input is 0.
logical operator "OR" gives an output of 1 when a minimum 1 input is 1.
logical operator "AND" gives an output of 1 when all inputs are 1.
Fortran Monitoring System was used as the High-level languages in second
generation operating systems.


Operating Systems

The operating system is essential software, coordinating all
activities between hardware and software components.
Operating systems perform basic tasks, such as recognizing ,
input from the keyboard,sending output to the display screen
keeping track of files and directories on the disk,
and controlling peripheral devices such as disk drives and printers.
As users, we normally interact with the operating system through
a set of commands.For example, the DOS operating system contains
commands such as COPY and RENAME for copying files and changing
the names of files, respectively. The commands are accepted and executed
by a part of the operating system called the command processor
or command line interpreter.Graphical user interfaces allow you to enter
commands by pointing and clicking at objects that appear on the screen.


Architecture of a computer

Computer Architecture is the science and art of selecting and
interconnecting hardware components to create computers that meet
functional, performance and cost goals. As with nature and its systems,
the evolution of computers and management information systems hasn’t been
logical or carefully planned. The evolution of computers in the last 50 or 60 years
is really remarkable. Mainly due to introduction of the new technologies in
electronics, the architecture of a computer went from vacuum tubes and magnetic
drums to transistors,from that to integrated circuits and today’s ULSI which
means Ultra-large Scale Integration made it possible to put millions of
components on a single chip. With each advance, computers became smaller,
cheaper, faster, more efficient and more powerful.
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Assignment 2



8-4-2-0 code is known as Binary code (False)
Second generation languages do not interact with the computer directly
A computer converts high-level languages programs into assembly-language programs.
What is the binary form of the difference between 237 and 132?
The difference is 105 in decimal in binary 01101001 and 237in binary is 11101101
And 132 in binary is 10000100.
List the advantages of assembly language:
Assembly language program could use words instead of the machine language.
With use of assembly language, programming became much faster and efficient.
The base or radix of the binary number system is : 0 and 1.
ABCD19 is an example of a hexadecimal number (False)
Machine level language is a low language because the CPU executes the
machine language instruction directly without interoperation (True)
What is the binary form of the sum 3C2 and 11F
Why do programs written in the fourth-generation language execute slowly.
Because of GUI, fourth-generation language consume a lot of processing power
And execute slowly compared with programs written in third-generation languages.
The CPU executes instruction given in assembly language directly without
interpretation (False)


Define Operating system.

The operating system is essential software, coordinating all
activities between hardware and software components.


Define Architecture of a computer

The design and implementation of computer system
in an organization.


Second generation language.

Second generation language also known as assembly language or assembler,
were introduced in the mid 1950s. A programming language that is once removed
from a computer's machine language.
Machine languages consist entirely of numbers and are almost impossible for
humans to read and write. Assembly languages have the same structure and set
of commands as machine languages, but they enable a programmer to use names
instead of numbers.


Third generation language.

Third generation language came into existance in the late 1950s.
A language designed to be easier for a human to understand,
including things like named variables.High-level language are also
known as procedural language because they use procedures.A procedure
is a set of instruction used in program and executed repeatedly.
A fragment might be Fortran, ALGOL and COBOL are early
examples of this sort of language. Most "modern"
languages (BASIC, C, C++) are third generation. Most 3G

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Assignment 3

Computer needs the operating system because operating system interacts
with the hardware and acts as an interface between the various hardware
components and commands given by the user
The programmer transferred the program to punch cards
Operator would load the cards on a card reader
The operator load a magnetic tape on a tape drive to record the card data
sequentially
The computer operator manually loaded a batch of several jobs on magnetic
tapes into the computer
The tape was then manually loaded and connected to an output device,
such as a printer
The entire process took a long time if an error occurred during the process
the entire program had to be rewritten and punched again, many programmers
had to wait for a long time to get their programs to be processed again
The improvement over the previous generation of operating systems was
these OS allowed many different programs to run at the same time,
this feature was called multi –Programming batch system
The disadvantage of multiprocessing batch operating systems was that they
could not support multiple users, but feature was included in the
time –sharing system, witch could handle many users at the same time
Process manager ensures that all programs get a fair share of the CPU
time between them
Memory manager handles requests for accessing memory from various programs
Device manager handles communication between CPU and other devices in
computer to perform various tasks
File manager manages the different files and folders stored in the computer
Commend interpreter waits for the user‘s command, reads and interprets it and
issues the corresponding control instruction to the operating system performs
the operation requested
Protection system ensures that only authorized users or programs can access the
recourses or files
Network users can share the hardware resources such a printer or a scanner,
it provides a communication link between users, making information available
to users at the right time and at a right place
Single tasking OS can support only a single task at any time. An example
of a single-tasking OS is MS-DOS
Multi-tasking OS can support more then one task at a time. An example of a
multi-tasking OS is Windows 95
An example of multi-tasking GUI based OS’s are Windows 95, Windows 98,
Windows NT, Windows 2000,Windows XP and Windows Server 2003
Some of the features of MS-DOS, it is 16 –bit OS which means that it
can send or receive 16 bits of information to the microprocessor for
processing 16 bits of data, it is a single-user and single–tasking OS,
it is easy to load and install
The most prominent and popular features of Microsoft Windows OS are
user-friendly GUI based and reliable
Operating systems that provide networking features are sharing the hardware
and software resources such a printer or a scanner, it provides a
communication link between users, making information available to users
at the right time and at a right place
An example of a full 32-bit OS are Windows 2000, Windows XP and
Windows Server 2003 Kernel is a software that schedules activities
that the CPU performs
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Assignment 4

Multi-tasking is the ability of a single processor to handle multiple
processes at the same time
In co-operative multi-tasking, each task utilize the CPU for as long as
it requires to perform the task
In pre-emptive multi-tasking system each program gets a specific amount
of CPU time allocated by OS
Multi-user, multi-tasking operating systems enable multiple users to simultaneously
use a single computer, each user can run multiple tasks
Multi-processing refer to multiple processors simultaneously executing two or
more processes or threads
In SMP , resources are shared and the workload is balanced among processors
In round- robin scheduling, uses the fixed amount of optimal time for which
a process executes is very important, each time process is scheduled to
be executed, it must start from exactly the point where it stopped before
In multi-programming environment, where many processes may be in the ready state
it is important to schedule processes to the processor, the process scheduler tracks
all the processes in the memory with the help of the process table
Two processes may share the same data, such interaction between two or more
processes is called inter process communication
In direct communication, a process sending the message must explicitly specify the
name of the recipient process, in indirect communication two processes
exchange massages
through shared mailbox
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Assignment 5

The differences between single-tasking and multi-tasking systems are user can’t
simultaneously execute various processes in single-tasking system but in
multi-tasking system it is possible.
Memory manager involves the following tasks:
Tracking memory usage
Allocating memory to processes
Releasing memory from processes
Removing processes from the main memory to their original location to create
space for new processes
Tracking memory usage means that memory manager uses various methods to allocate
and de-allocate memory to processes
Allocating memory to processes means that memory management is allocating memory
for processes to be executed
Releasing memory is de-allocating memory after the process is executed
Removing processes from the main memory means that the memory manager removes
one or more processes from the main memory that are not needed and allocates
the memory to the new process,this technique is called swapping, the process
swapped between the main memory and the backing store or the swap space
Memory manager differ in single-user single tasking system perform only
one process can execute at a given point of time, however in the multi-tasking
OS multiple processes execute at the same time
The dormant processes are stored temporarily in area of secondary memory
called the backing store
Disk caching enables faster access to frequently accessed files, when
a program reads data from a file or writes to it the contents of
the file are first stored in the disk cache and if the same program or
a different one requests the same data in the future from the same file
it is retrieved from the disk cache instead of reading it
again from the hard disk
Methods used by an OS to allocate memory processes are fixed partition
method, dynamic partition method and relocatable partition method
Fixed portion method, memory is divided into a number of equal or unequal fixed
partitions and a process is allocated to the free partition
Dynamic partition method the memory is divided according to the size of
the process
Relocatable portion method a process can be relocated in the memory without
affecting any other instructions
Memory manager using bit maps in this technique memory is allocated in
multiples of a fixed size called allocation units, the bits for all the
allocations units are organized into a table called the bit map, list
is another technique of keeping track of memory usage in this technique
the memory manager keeps track of the allocating units in theform of the list
When an instruction tries to access a page that is not mapped, a signal
or trap is send to the processor this trap is called a page fault, when
the page fault occurs the OS swaps the last used page frame to the disk
and marks it as unmapped and the page for which the page fault has occurred
is then loaded to the physical memory and the mapping is changed accordingly
When the page fault occur causing existing pages to be swapped to disk so
that memory can be allocated to the process if this swapping page happens
frequently the OS spends more time in swapping pages then in other useful
activities because the process take alot of time, this condition
called trashing to avoid trashing add more physical memory to the system
Memory manager unit which maps virtual pages to page frames uses page table,
page table contains page frame number and the information stating whether or
not a page is mapped to this page frame each page in the page table has a
virtual address
Segmentation is the process of dividing the memory into logical sections
where each section consist of multiple frames
Virtual memory is the memory space assigned to a process when the
process available physical memory space
MS-DOS is single –user system that does not natively support multi-tasking
The difference between techniques of Paging and of Segmentation is that
in technique< of paging parts of process that is not active are being
swapped out thereby utilizing memory more effectively and demand on
I/O are significantly less because the entire
process is not
being swapped and segmentation is the technique of dividing the memory
into logical sections where each section consist of multiple frames, memory
is also allocated for processes in the segments rather than frames
MS-DOS environment consists of four segments code segment data segment, stack
segment and extra segment .The code segment consist of code or instructions,
data segment consist stack segment is used to store a process temporary data and extra
segment used for temporary computations as a scratch pad, each
segment is 64 KB
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“Pirates of Silicon Vale”


The personal computer is the most widely used computer today. However 25-30
years ago personal computers didn’t exist. The personal computer technology is
growing very fast
The movie “Pirates of Silicon Vale” shows us the people of that time who
started thisall personal computer technology. In the movie we see two
characters Steve Jobs and
Bill Gates started almost from nothing and how they build their companies
that now everyone knows in around the world in our time. In that movie we
can see a lot of different things about Steve and Bill and how they
fighting for their ideas, also we can see what kind of people they really
are and what driving them to achieve their goal
However movie “Pirates of Silicon Vale” is not only about them it is also
about the revolution in the computer industry and how industry is grooving.
I think that computer industry have a very big influence on everything,
we can see computers everywhere we look
People now day’s use computer in almost every aspect of their life’s
including business and personallife all industries and businesses use
personal computers too as a very useful and remarkable tool.


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Assignment 6



A mechanical component is called a device and an electronic
component is called a device controller. A device controller
Acts as interface between the peripheral devices and the CPU
The checksum is a count of the number of bits stored in one block
And is the binary format
A block device is compares the calculated value of the checksum
with the value on the value on the hard-disk block
The device controller raises an interrpt.An interrupt is a signal
from the hardware to the operating system that causes the operating
system pause its current operation and take appropriate action
UNIX implements I/O using a collection of device driver, in
Which each driver typically controls one type or class of devices
In Windows 9x, devices are installed using the plug-and-play feature
Plug-and-play is a set of specifications that enables you to plug in device
and play it without configuring the device manually. The operating system
automatically configures itself so that it can attach devices, such as the
VDU and printer. Windows 2000 also supports the plug-and-play feature


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Assignment 7

ClI is Command line interface, MS-DOS, UNIX AND Virtual memory
system(VMS) are examples of operating system that use CLI
GUI is Graphical User interface
Pointer: A symbol, typically an arrow or cursorPointing Device: A mouse
or joystick that helps move the pointer on the screen
Windows: Separate instances of the GUI that can concurrently run separate
programs
Menus; lists of commands that can be selected and executed
Icons: Graphics that are used to represent a file or an application
Human Computer Interface is a field of study that deals with the design,
development, and implementation of interfaces for computer system,
considered from the human perspective
Human Interface Device is any device that interfaces between human and computers
Many network administrators prefer to use CLI over GUI because CLI provides more
flexibility to execute commands and also they more familiar with CLI-based administrative
commands, Switches and parameters than a GUA
Click on star button, go to run and type cmd press enter
Rename command using syntax of OS Linux mv OS.doc operatingsystem.doc
Rename command using syntax of Windows 2000 ren D: OS.doc opeartingsystem.doc
D: CD oparetingsystem.doc
In order to obtain syntax for a particular command in MS-DOS user
should type help in front of the command and press enter and that
would give the user syntax of the command that is in question
In order to obtain the information about copy command in MS-DOS first
step would be type help on the command line and user should get description
of the copy command or any other command in MS-DOS, in Windows 2000
to get information on copy command user have to click on start button go
to run type cmd to invoke the DOS prompt and type help and user should
get description of copy command or any command that exist in Windows 2000
in Linux operating system user have click on the terminal icon accessing
the command prompt in Linux type man and copy or any command in that
matter and information about commands will be displayed
First step in MS-DOS would be type dir command on the command line and type
file name that is in search then type /s parameter and search will
go through all subdirectories
To search for a file in Linux user can use find command first step would be
click on the terminal icon accessing the command prompt in Linux type find
command and the file name and press enter
In Windows 2000 first step would be click on the start button go to search
and pick the option For Files or Folders, in the Search Result dialog box
that appears enter the search criteria in the Search for files or folders
named field and Click Search Now to start the search
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Assignment 8



Cluster function is the way OS groups the sectors into clusters to affect the
performance of the operating system
All Windows-based operating systems support file names with two parts, a period
is used to separate the two partsof the file name, first part of the file
name is called primary name and the second part is called the file extension
The attributes to a file in the Windows environment are: Read only attribute
to a file means that user can only read data
From the file but not modify or delete the file.
Hidden attribute determines whether or not a file will be visible as
a part of the directory listing in which it exits
System attribute determines whether or not a file will be visible as a part
of the directory listing in which it exits this attribute is used by the
operating system and some application to indicate the files that are
required to execute the application or operate the operating system
Archive attribute determines whether the file will be backed up by
a backup software
Sequential access method is the simplest access method, in this method
information is accessed from the first block of information to the next
in a sequential order
Direct Access Method allows read and write operation in the random blocks
this means that you can read and modify the blocks without following any
specific order
Indexed Access Method is based on the direct access method, in this
method, an index for a file that contains pointer to different block
of information in the file is created
Contiguous Allocation Method in this method each file is allocated a set
of adjacent block and on the disk, each file identified by the disk address
of the first block and the space allocated to it
Linked List Allocation each file is regarded as a linked list of disk blocks that
are scattered on the disk
Indexed Allocation Method allows files to be accessed directly or sequentially,
in this method all the pointers are located at one place known as the
index block
FAT 12 file system was used by the earlier versions of MS-DOS operating
system, such as MS_DOS v1.x and MS-DOS v2x
FAT 12 uses 12-bit binary number and as result address 4096 different
cluster locations, individual cluster size used in FAT 12 renges between
0.5 KB to 4 KB for this reason the maximum partition size supported
by FAT 12 is 16 MB
FAT 16 uses 16-bit binary number to store the cluster locations and for this
reasons the maximum number of cluster can be 65,536 and FAT 16 supports
a maximum hard disk partition of 2 GB that would be the main difference
between FAT 12 and FAT 16 in
FAT 32 file system supports a maximum partition size of 2 TB, in addition to
supporting a higher partition size FAT 32 increases disk efficiency by
optimizing the cluster size used by the FAT 32 depending on the hard
disk size
That would be a main difference between FAT12, FAT16, FAT32 the maximum number
of clusters and partition sizes and disk efficiency by optimizing the cluster
sizes NTFS has four features that promote security and data reliability
are: Disk quotas, Encrypting file system, Sparse file support and
NTFS change journals
UFS is the UNIX File System was introduced with the UNIX operating system UFS
stores files and directories in a hierarchical structure on the hard disk
EXT FS is Extended File System is designed for use with Linux operating system
In Unix/Linux the file and folder permissions are read write and execute, the
operating system decides which user has what permissions based
on the authorization or owner of the file, the OS commonly use password to
handle security, each user has a unique user name and
password combination
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Assignment 9



A computer network is a mechanism in which a group of computers and associated
devices are connected to facilitate exchange of resources among the
computers connected
Computer network has following advantages:
Remote access to programs and data
Provide improved communication facilities
Enable resource sharing
Provide backup and failover
A network protocol is a set of rules that define and enable the exchange of
data over a network
TCP is a connection-oriented transport layer protocol responsible for
sequencing, acknowledging, and ensuring integrity of the data packets
IP is a connectionless packet-switched network layer protocol that
performs addressing and route selection
The difference between TCP and IP is TCP responsible for sequencing,
acknowledging, and ensuring integrity of the data packets and IP
performs addressing and route
selection UDP is not connection-oriented
and does not require an acknowledgement for
data receipt, for this
reason UDP is less reliable than TCP
In peer-to-peer network, no single computer plays the role of server and on
client server network, the server acts as the central points for
exchange of data
A client-server network has the following advantages over peer-to-peer network
Consists of powerful and dedicated server that provides access to resources
Supports a large number of workstations
Manage a large number of users with a relative degree of ease
Implement higher security control
The process to send information from one computer on a network to another
computer on the network is called routing, this process consists of
activities, such as the task to determine the optimal routing paths
and transmit data over a network
The following indicators are used in performance evaluation:
Network response time
Throughput
Cost
Network Load
The network features offered by Windows NT 4.0
Network Monitor: Is a diagnostic tool to monitor the traffic on the network
Internet Information Server (IIS): Allows user to host Web sites on their computer
RAS : Provides remote access to a server
Gateway Services for NetWare(GSNW) and Client Server for NetWare (GSNW)
Allow Network administrator to connect a Windows NT computer to a NetWare
Server using IPX/SPX
Windows NT 4.0 server was unable to address the issues of encryption data on the
network and management on large network
Windows 2000 Server offer the feature the feature of encryption of all the
data present on a network, so that the data is not readable
Network features of Unix and Linux
Network File System (NFC), Samba, Network Information Services (NIS)
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"Office Space"

Peter Gibbons (Ron Livingston) is a computer programmer working for
Initech in Houston. Every day, he and his friends Samir (Ajay Naidu)
and Michael Bolton (David Herman as not THAT Michael Bolton), suffer
endless indignities and humiliations in their soulless workspace from
their soulless boss, Bill Lumbergh (Gary Cole). For Peter, stuck in
his cookie-cutter apartment with paper-thin walls and IKEA furniture,
every day is worse than the one before it -- so every day is the worst
of his life. To cap it off, Initech has hired a pair of "efficiency
experts" to downsize the company. One Friday night, Peter's soon to be
ex-girlfriend Anne (Alexandra Wentworth) forces him to go to an
occupational hypnotherapist to relieve work stress. While Peter is
under hypnosis, the therapist keels over and dies. As he never snaps
out of his hypnotic state, Peter has a new outlook on life. If
something annoys him, he just ignores it or walks away from it.
He is completely relaxed and enjoying life for the first time in a
long time. On Monday, Peter skips work and sleeps in. He gets up for
lunch and drives down to a restaurant next to his office and asks the
waitress he's had a crush on, Joanna (Jennifer Aniston), on a date. When
Peter stops into the office to pick up his organizer, he's called in to
talk to the efficiency experts. Relaxed and friendly, Peter charms them
as he describes everything wrong with the office, including his boss.
Even as Peter now appears at work only as the mood strikes him, the experts
decide he's management material and give him a promotion even as they lay
off the hardworking Samir and Michael. Peter then convinces his friends to
exact revenge on Initech based upon an idea from Superman III. Not everything
works out quite as planned.
Offece Space originated from writer/director Mike Judge's first animated
short of the same name, created in 1991. The short was about Milton
(reproduced in the film by Stephen Root), a damaged office drone whose
complaints and threats about his sufferings go unheeded. ~ Ron Wells,
All Movie Guide
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Homework



Assignment 10


In a computer environment, security measures need to ensure the following:
Confidentiality: Confidentiality ensures that only authorized user can access data
Integrity: Integrity ensures that the data is reliable
Availability: Availability ensures that data is available to authorized users when
required
Physical Security: This includes protecting a computer from theft, tampering,
and natural disasters
Software and Data Security: Unauthorized users may tamper with the installed software
or may also access data through shortcomings in the software and the operating system
To secure a stand-alone computer, you need to take into account the following:
Location: Place the computer in a place where it cannot be tampered with
User accounts: Set up an individual account for each user
Password protection: Ensures that the passwords used are hard to crack and secure
Access rights: Provide access to only authenticated user
Data encryption: Encrypt data in the computer to ensure its confidentiality
Backups: Ensure that backups of the software and data are taken at frequent intervals
In an active hack attack, a hacker attempts to access target computer for
utilizing their resourcesand data
In an passive hack attack involves eavesdropping over the network
A causes for denial-of-service are destruction or alternation outage and
recourse exhaustion
Firewall is generally is installed at point where the secure internal network and the
un-trusted external network meets this point is known as the choke point
The difference in misuse detection and in anomaly detection is the misuse detection,
an IDS Analyzes logged information and compares it with existing attack signature
available in attack documentation and in anomaly detection the security
administrator defines the baseline for the network traffic load, protocol and packet
size and IDS then compares the current data on network segment with the baseline to
detect anomalies
A computer virus attaches itself to documents and executable file and every
time the file is executed virus is replicate it self
There are two main types of account User account and Group account
Anti-virus software works with the operating system so when you open a file the
anti-virus program cheeks the file for any infections
Data encryption is the process of encoding data to protect it from unauthorized
access