Strand 3: IT Systems

3.3 Networks

Network Operating systems and utility software

What is a Network Operating System?
Unlike normal operating systems, such as Windows, that are designed to control stand alone pc’s, network operating systems were designed to control all the pc’s on the network. The network operating system acts as a boss to keep the network running smoothly.
The two major types of network operating systems are:

  • Client/Server
  • Peer-to-Peer

Client/server network operating system allows the network for central storage and control. File servers are the heart of a Client/server network as they provide the resources and the security needed. Individual workstations have access to the resources available on the file servers. The network operating system provides the mechanism to integrate all the components of the network and allow multiple users to simultaneously share the same resources irrespective of physical location. Novell and windows Server 2008 are popular examples of client/server network operating systems.

Fig. 2. Client/server network

Advantages of a client/server network:
· Centralized - Resources and data security are controlled through the server.
· Scalability - Any or all elements can be replaced individually as needs increase.
· Flexibility - New technology can be easily integrated into system.
· Interoperability - All components (client/network/server) work together.
· Accessibility - Server can be accessed remotely and across multiple platforms. Cross platform compability.
Disadvantages of a client/server network:
· Expense - Requires initial investment for dedicated server is expensive.
· Maintenance - Large networks will require a staff to ensure efficient operation.
· Dependence - When server goes down, operations will cease across the network.

P2P network operating systems allow users to share resources and files located on other pc’s. However, they do not have a file server or a central place where everything is stored. In a P2P network, all the computers are considered to be equal and have the same user access rights. P2P networks are mainly designed for small scale usage e.g. home or office. AppleShare and Windows for workgroups are examples of programs that can function as P2P network operating systems.

Fig. 1. Peer-to-peer network

Advantages of a peer-to-peer network:
· Less initial expense - No need for a dedicated server.
· Setup - An operating system (such as Windows XP) already in place may only need to be reconfigured for peer-to-peer operations.
Disadvantages of a peer-to-peer network:
· Decentralized - No central place for storage of files and applications.
· Security - Does not provide the security available on a client/server network.

Network Operating System Software
The following links include some of the more popular peer-to-peer and client/server network operating systems.
· Macintosh OSX
· Microsoft Windows Server
· Novell