Definition of Network Operating System in the Network Encyclopedia.
What is NOS (Network Operating System)?
A Network Operating System, also known as NOS, is a computer operating system that is network-aware. Network operating systems (NOS’s) typically provide support for features such as the following:
- File and printer sharing
- Data security and authentication
- Distributed applications
- Centralized administration
You can use a NOS to create local area networks (LANs) that function as either peer-to-peer networks or server-based networks, depending on your needs and budget. Examples of NOS’s include Microsoft Windows NT, Novell NetWare, and Banyan VINES. Cisco’s Internetwork Operating System (IOS) is an example of a Network Operating System that runs not on computers but on internetworking devices such as routers.
History of Network Operating System
Early microcomputer operating systems such as CP/M, DOS and classic Mac OS were designed for individual computers. Packet switching networks were developed to share hardware resources, such as a mainframe computer, a printer or a large and expensive hard disk.
During the 1980s the need to integrate dissimilar computers with network capabilities grew and the number of networked devices grew rapidly. Partly because it allowed for multi-vendor interoperability the TCP/IP protocol suite became almost universally adopted in network architectures. Therefore computer operating systems and the firmware of network devices needed to reliably support the TCP/IP protocols.