Understanding network architectures

When talking about computer networks, actually we are talking about the essential and broader concept of the elements that make up a computer network. In this form of discussion, while the computer network types deal with the area coverage, the physical and logical topologies deal with the physical arrangement and logical structure of the computer network. Having said that, the computer network architecture represents the computer network design that allows the computer network components to communicate with one another. Usually, there are two types of architectures in a computer network:

• Peer-to-peer networking (P2P): This is a computer network in which the participating computers do not play the predefined roles in the network, instead they change roles from client to server and vice-versa based on the actual activity on the network. For example, if computer A is accessing resources from computer B, then computer A acts as the client while computer B acts as the server. After some time, if computer B accesses resources from computer A, then computer B becomes a client and computer A becomes a server. As you may notice, they switch roles based on who is requesting and who is providing a resource on the network. Figure 1.1 presents an example of peer-to-peer networking:

Figure 1.1. Peer-to-peer computer network

• Client/server networking: This is a computer network in which participating computers have a predefined role. That means that in this computer network architecture, computers that access resources act as clients, while computers that provide resources act as servers. In general, this is a computer network architecture with dedicated servers that provide resources on the network. Mid-sized and enterprise computer networks are the best example of the client/server computer network. Figure 1.2 presents an example of client/server networking:

Figure 1.2. The clients/server computer network

Another way to categorize computer networks is by their topology, or the way in which nodes are arranged and connected to one another, and how they communicate. The computer network mainly recognizes two types of topologies: physical and logical topologies.