OPERATING SYSTEM
TYPES OF OPERATING SYSTEM
1. Batch Operating System
2. Multiprogramming operating system
3. Time-Sharing Operating Systems
4. Distributed Operating System
5. Network Operating System
1. Batch Operating System
This type of operating system does not interact with the computer directly. There
is an operator which takes similar jobs having the same requirement and group
them into batches. It is the responsibility of the operator to sort jobs with similar
needs.
Advantages of Batch Operating System:
It is very difficult to guess or know the time required for any job to complete.
Processors of the batch systems know how long the job would be when it is in
queue
Multiple users can share the batch systems
The idle time for the batch system is very less
It is easy to manage large work repeatedly in batch systems.
Disadvantages of Batch Operating System:
The computer operators should be well known with batch systems
Batch systems are hard to debug
It is sometimes costly
The other jobs will have to wait for an unknown time if any job
fails
Examples of Batch based Operating System: Payroll System,
Bank Statements, etc.
2.MULTIPROGRAMMING OPERATING SYSTEM
when two or more programs reside in memory at the same time, is referred
as multiprogramming. Multiprogramming assumes a single shared processor.
Multiprogramming increases CPU utilization by organizing jobs so that the CPU
always has one to execute.
An OS does the following activities related to multiprogramming.
The operating system keeps several jobs in memory at a time.
This set of jobs is a subset of the jobs kept in the job pool.
The operating system picks and begins to execute one of the jobs in the
memory.
Multiprogramming operating systems monitor the state of all active programs
and system resources using memory management programs to ensures that the
CPU is never idle, unless there are no jobs to process.
Advantages
High and efficient CPU utilization.
User feels that many programs are allotted CPU almost
simultaneously.
Disadvantages
CPU scheduling is required.
To accommodate many jobs in memory, memory management is
required.
user gets the time of CPU as they use a single system. These systems are also
known as Multitasking Systems. The task can be from a single user or different
users also Each task is given some time to execute so that all the tasks work
smoothly. Each. The time that each task gets to execute is called quantum. After
this time interval is over OS switches over to the next task.
Advantages of Time-Sharing OS:
Each task gets an equal opportunity
Fewer chances of duplication of software
CPU idle time can be reduced
3. Time-Sharing Operating Systems
Disadvantages of Time-Sharing OS:
Reliability problem
One must have to take care of the security and integrity of user programs and
data
Data communication problem
Examples of Time-Sharing OSs are: Multics, Unix, etc.
4. Distributed Operating System
These types of the operating system is a recent advancement in the world of
computer technology and are being widely accepted all over the world and, that
too, with a great pace. Various autonomous interconnected computers
communicate with each other using a shared communication network.
Independent systems possess their own memory unit and CPU. These are referred
to as loosely coupled systems or distributed systems. These system’s processors
differ in size and function. The major benefit of working with these types of the
operating system is that it is always possible that one user can access the files or
software which are not actually present on his system but some other system
connected within this network i.e., remote access is enabled within the devices
connected in that network.
Advantages of Distributed Operating System:
Failure of one will not affect the other network communication, as all systems are
independent from each other
Electronic mail increases the data exchange speed
Since resources are being shared, computation is highly fast and durable
Load on host computer reduces
These systems are easily scalable as many systems can be easily added to the
network
Delay in data processing reduces
Disadvantages of Distributed Operating System:
Failure of the main network will stop the entire communication
To establish distributed systems the language which is used are not well defined yet
These types of systems are not readily available as they are very expensive. Not
only that the underlying software is highly complex and not understood well yet
Examples of Distributed Operating System are- LOCUS, etc.
5. Network Operating System
These systems run on a server and provide the capability to manage data, users,
groups, security, applications, and other networking functions. These types of
operating systems allow shared access of files, printers, security, applications, and
other networking functions over a small private network. One more important
aspect of Network Operating Systems is that all the users are well aware of the
underlying configuration, of all other users within the network, their individual
connections, etc. and that’s why these computers are popularly known as tightly
coupled systems.
Advantages of Network Operating System:
Highly stable centralized servers
Security concerns are handled through servers
New technologies and hardware up-gradation are easily integrated into the
system
Server access is possible remotely from different locations and types
of systems
Disadvantages of Network Operating System:
Servers are costly
User has to depend on a central location for most operations
Maintenance and updates are required regularly
Examples of Network Operating System are: Microsoft Windows Server
2003, Microsoft Windows Server 2008, UNIX, Linux, Mac OS X, Novell
NetWare, and BSD, etc.
6. Real-Time Operating System
These types of OSs serve real-time systems. The time interval required to
process and respond to inputs is very small. This time interval is
called response time.
Real-time systems are used when there are time requirements that are very
strict like missile systems, air traffic control systems, robots, etc.
Two types of Real-Time Operating System which are as follows:
Hard Real-Time Systems:
These OSs are meant for applications where time constraints are very strict and
even the shortest possible delay is not acceptable. These systems are built for
saving life like automatic parachutes or airbags which are required to be readily
available in case of any accident. Virtual memory is rarely found in these
systems.
Soft Real-Time Systems:
These OSs are for applications where for time-constraint is less strict.
Advantages of RTOS:
Maximum Consumption:Maximum utilization of devices and system, thus
more output from all the resources
Task Shifting:The time assigned for shifting tasks in these systems are very
less. For example, in older systems, it takes about 10 microseconds in shifting
one task to another, and in the latest systems, it takes 3 microseconds.
Focus on Application:Focus on running applications and less importance to
applications which are in the queue.
Real-time operating system in the embedded system:Since the size of
programs are small, RTOS can also be used in embedded systems like in
transport and others.
Error Free: These types of systems are error-free.
Memory Allocation:Memory allocation is best managed in these types of
systems.
Disadvantages of RTOS:
Limited Tasks:Very few tasks run at the same time and their concentration is
very less on few applications to avoid errors.
Use heavy system resources:Sometimes the system resources are not so good
and they are expensive as well.
Complex Algorithms:The algorithms are very complex and difficult for the
designer to write on.
Device driver and interrupt signals:It needs specific device drivers and
interrupts signals to respond earliest to interrupts.
Thread Priority:It is not good to set thread priority as these systems are very
less prone to switching tasks.
Examples of Real-Time Operating Systems are: Scientific experiments,
medical imaging systems, industrial control systems, weapon systems, robots,
air traffic control systems, etc.
