Architecture/topology of networks¶

The topology of a network describes the structure of the connections of several participants with the aim of ensuring a common data flow.

The topology of a network is one of the factors that determine its reliability: only if there are redundant paths between the nodes can individual connections or devices (such as a switch) remain functional if they fail. In this case, there are one or more alternative paths in addition to the working path.

A distinction is made between physical and logical topology.

• The physical topology describes the structure of the network cabling.
• The logical topology describes the data flow between the end devices.

Knowledge of the basic architecture of a network is required to evaluate its performance, reliability, the dimensioning of potential investment costs and for the selection of suitable hardware.

Topologies¶

The topologies most frequently used in practice are shown below in simplified form.

In large corporations and associated productions, structures can also be found that are made up of several different topologies.

Client-server architecture¶

The client makes a request to use a particular service to the server, which in turn receives the request, evaluates it and serves the client by providing the desired service. This communication takes place by means of so-called transactions. A transaction must fulfill certain criteria. For example, it must not influence any other transactions and must leave a consistent database after its execution.

Example versiondog¶

A user wants to edit the project data of a specific system.

The UserClient requests the project data from the versiondog server through a Check-Out. The user can now use and modify this project data through their locally installed application. If this change is now to become effective and bindingly versioned, a Check-In is requested from the server, a storage of the new project version.

Check-Out and Check-In therefore represent transactions.

This is a simplified representation of the processes that play a role in client-server communication.