Purpose of networks

We see so many networks around us. Each network has a specific purpose for which it is built. For example, the primary purpose of the networks that we see in computer labs is to provide access to shared resources, most notably printers and data storage. The networks in the manufacturing plant are meant to carry control signals for the various plant machinery that are connected on the network. The military and defense networks have a totally different purpose.

Since the networks are supposed to deliver different services to the end users, the design of the network will be different, and will be defined by the characteristics of the services to a large extent. Hence, the starting point for planning a network is to define the services that the network will offer, so that the network can be built accordingly.

Once the network is built, and starts offering services to the end users, it needs to be operated, and changes need to be made on the network on a day-to-day basis. The operations include monitoring the network for critical network parameters, and taking corrective action in case of network incidents such as outages/performance degradations. The changes might also include adding new services or deleting or modifying any existing services on the network. The network operations depend upon the way the network is designed, and the services it is running. For example, for a network that is not built with adequate redundancy, the operations approach has to be very different than that for a network that has enough resiliencies built in the network.

These concepts have been widely described and used in the frameworks used for network architectures, for example, for the Services, Network, Operations (SNO) approach, or the Services Oriented Network Architecture (SONA) framework proposed by Cisco.