A network operating system (NOS) provides services to clients over a network, enabling file sharing, printing, and application access. It handles typical network duties like remote access, routing, security, and administration. Well-known NOSes include Windows Server, Linux, and Mac OS X. In a client-server network, servers run the NOS to provide centralized resources to client computers running other operating systems. Common server types are file servers, print servers, mail servers, application servers, and database servers.

1. Network
Operating System
(NOS)

2. What does Network Operating System
(NOS) mean?
A network operating system
is an operating system
designed for the sole
purpose of supporting
workstations, database
sharing, application sharing
and file and printer access
sharing among multiple
computers in a network.
Certain standalone operating systems,
such as Microsoft Windows NT and
Digital’s OpenVMS, come with
multipurpose capabilities and can also act
as network operating systems.
WELL-KNOWN NETWORK
OPERATING SYSTEMS * Microsoft
Windows Server 2003,
* Microsoft Windows Server 2008,
* Linux and Mac OS X.

3. Features of Network
Operating Systems
• provides a platform for both the functionality
of an individual computer and for multiple
computers within an interconnected network.
Basically, a network operating system
controls other software and computer
hardware to run applications, share
resources, protect data and establish
communication. Individual computers run
client operating systems, while network
systems create the software infrastructure for
wireless, local and wide area networks to
function.

4. Basic Operating Features
Network operating systems support the basic underlying
operating features of networks. These include support for
processors and the various protocols that allow computers to
share data. Many network operating systems can detect
hardware within the system to allow for asset discovery
within the network. Also, network operating systems support
the processing of other software applications that run on both
individual computers and within the network.

5. A network
operating system
(NOS) provides
services to clients
over a network.
Both the
client/server and
peer-to-peer
networking models
use network
operating systems,
and as such, NOSes
must be able to
handle typical
network duties
such as the
following:
Providing access to remote printers, managing which users are using
which printers when, managing how print jobs are queued, and
recognizing when devices aren't available to the network
Enabling and managing access to files on remote systems, and
determining who can access what—and who can't
Granting access to remote applications and resources, such as the
Internet, and making those resources seem like local resources to the
user (the network is ideally transparent to the user)
Providing routing services, including support for major networking
protocols, so that the operating system knows what data to send where
Monitoring the system and security, so as to provide proper security
against viruses, hackers, and data corruption.
Providing basic network administration utilities (such as SNMP, or
Simple Network Management Protocol), enabling an administrator to
perform tasks involving managing network resources and users.

6. Peer to Peer Networks
A peer to peer network has no dedicated servers. In a peer to
peer network, a number of workstations (or clients) are
connected together for sharing devices, information or data.
All the workstations (clients) are considered equal. Any one
computer can act as client or server at any instance. This
network is ideal for small networks where there is no need for
dedicated servers, like home networks, small business
networks, or retail shops. The Microsoft term for peer to peer
network is “Workgroup”.

7. Peer to Peer Networks
There is no
limitation for the
number of
computers in a
peer to peer
network. But peer
to peer
implementations
are meant for small
networks. Typically,
a Workgroup
contain less than
10 workstations.
Commonly used
Workstation
Operating Systems
are Microsoft
Windows 10
Desktop, Red Hat
Enterprise Linux
Workstation, SUSE
Linux Enterprise
Desktop, Ubuntu
Desktop, LinuxMint,
Fedora
Workstation,
elementary OS etc.

8. Client Server Networks
Peer to peer computer networks are good choice for small business organizations.
For example: a small pharmacy outlet, an automobile service center, a small clinic
etc.
The main disadvantages of peer to peer networks are listed below.
• Everything is kept distributed in different computers.
• User generated files are stored in individual computers. Data backup is extremely
difficult.
• Each computer has its own user database. There is no centralized user & user
privilege
management. Users need to remember their user ids and passwords in every
computer. Managing network users is extremely difficult.

9. "Client Computer” and "Server Computer"
What is a client computer?
A computer which is seeking any resource
from another computer is a client computer.
For Example: Downloading a file from a File Server, Browsing
Intranet/Internet etc. The network user normally uses a client
computer to perform a day to day work.

10. What is a Server Computer?
If a computer has a resource which is served to
another computer, it is a server computer.
The client establishes a connection to a server and accesses the services installed
on the server. A server is not meant for a network user to browse in internet or to do
spreadsheet data entry work. A server computer is installed with appropriate
Operating System and related software to serve the network clients with one or more
services.
In a client server network, high-end servers, installed with the Network Operating
System (Server Operating System) and the related software, serve the clients
continuously on a network, by providing them with specific services

11. Well known Server Operating System
Products are:
Microsoft Windows Server, Unix (Oracle Solaris,
IBMAIX, HP UX, FreeBSD, NetBSD, OpenBSD,
Xinuos Open Server/SCO Unix, GNU/Linux
(RedHat Enterprise Linux, Debian Linux, SUSE
Linux Enterprise Server, Ubuntu Server, CentOS
Server, Fedora Server etc.

12. Building a client server-based network is costlier
than building a peer-to-peer network. Client server-
based networks require dedicated servers. Server
hardware is costlier than normal desktop client
computer hardware. Network Operating Systems
(Server Operating System) are also costlier than
client Operating Systems (Desktop Operating
Systems).

13. Client
Server
Network

14. Different Types of Servers Used in Client Server Based Networks
• File Server: File servers are used to store the user documents and
files centrally. An ideal file server should have a large amount of memory
and storage space, fast hard-disks, multiple processors, fast network
adapters, redundant power supplies etc.
The main advantage of keeping network user files and electronic
documents centrally in a file server is that the network user files and
documents can be managed (backed up) easily. Think about managing
network user files and electronic documents kept distributed inside user
workstations in a network consists of thousands of computers! Nearly
impossible.

15. Print Server: Print Server, which redirects print jobs from client
computers to specific printers.
• Mail Server: Mail Servers are used to transmit emails using
email protocols. Most widely used email transmission protocol
is SMTP (Simple Mail Transfer Protocol). Mail Servers
exchange emails between different domains. Most widely used
Mail Server software products are Microsoft Exchange Server,
SENDMAIL (now proofpoint), Postfix, Apache James etc.
Different Types of Servers Used in Client Server Based Networks

16. Application Server: Common computer applications or
programs which are required by different network users can be
run in a central server, which enables multiple network users to
access common network applications from the network.
Typically, Application Servers run business logic. Means that,
every business is different and the Application Server is the
Server Software which controls the business process.
Some examples for Application Server Software are SAP ERP,
Microsoft Dynamics, Oracle ERP Cloud, Ramco ERP, infor ERP
etc.
Different Types of Servers Used in Client Server Based Networks

17. Database Server: Database Server allows authorized network
clients to create, view, modify and/or delete an organization's
data, stored in a common database.
Examples of Database Management Systems are Oracle
Database Products, Microsoft SQL Server 2019, PostgreSQL,
IBM DB2 Database Server, MySQL Database Server, Informix,
MongoDB, MariaDB Server etc.
• Directory Servers: Directory Servers allows the central
administration and management of network users and network
resources. Directory Servers provide the basic functions of
network security, Authentication, Authorization and Accounting.
Different Types of Servers Used in Client Server Based Networks

18. Direction: Read each item carefully and write your answers in your
notebook. Write TRUE if the statement is correct and FALSE if
otherwise.
___________ 1. Client server is essentially between processes
running on separate computers interconnected by
a computer network.
___________ 2. Computers are very powerful tools.
___________ 3. Server are used to manage business databases.
___________ 4. Database Servers allows authorized network
clients to create, view, modify/delete an
organization’s data stored in a common database.
___________ 5. Network Configuration is the overall design of some
type of communications network.
Please get ¼

19. Direction: Read each item carefully and write your answers in your
notebook. Write TRUE if the statement is correct and FALSE if
otherwise.
___________ 1. Client server is essentially between processes
running on separate computers interconnected by
a computer network.
___________ 2. Computers are very powerful tools.
___________ 3. Server are used to manage business databases.
___________ 4. Database Servers allows authorized network
clients to create, view, modify/delete an
organization’s data stored in a common database.
___________ 5. Network Configuration is the overall design of some
type of communications network.
TRUE
TRUE
TRUE
TRUE
TRUE