Routing

Routing is the process of selecting best paths in a network. In the past, the term routing was also used to mean forwarding network traffic among networks. However this latter function is much better described as simply forwarding. Routing is performed for many kinds of networks, including the telephone network (circuit switching), electronic data networks (such as the Internet), and transportation networks.

Switching

Switches can be a valuable asset to networking. Overall, they can increase the capacity and speed of your network. However, switching should not be seen as a cure-all for network issues. Before incorporating network switching, you must first ask yourself two important questions: First, how can you tell if your network will benefit from switching? Second, how do you add switches to your network design to provide the most benefit?

Security

Network security consists of the provisions and policies adopted by a network administrator to prevent and monitor unauthorized access, misuse, modification, or denial of a computer network and network-accessible resources. Network security involves the authorization of access to data in a network, which is controlled by the network administrator. Users choose or are assigned an ID and password or other authenticating information that allows them access to information and programs within their authority.

Wireless

A wireless network is any type of computer network that uses wireless data connections for connecting network nodes.
Wireless networking is a method by which homes, telecommunications networks and enterprise (business) installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. Wireless telecommunications networks are generally implemented and administered using radio communication. This implementation takes place at the physical level (layer) of the OSI model network structure.