A point-to-point connection is a permanent direct communication link between two parties. Unlike a dial-up connection, it does not need to be established via dial-up or disconnected following communication. In the early stages of the telecommunication age, these connections often consisted of circuit-switched landlines. Today, point-to-point connections are achieved in modern telecommunication networks via superordinate multiplex hierarchies or fibre-optic networks. Depending on the type, P2Ps can be used to transmit analogue or digital information. Bit transparency is a typical characteristic of a digital P2P. A point-to-point connection has to be installed by a provider and made available to the customer in order to be used for communication purposes.
There are different types of point-to-point connections with differing bandwidths depending on the application. Common designations are the product names used by Deutsche Telekom such as direct data link (Datendirektverbindung - DDV) or standard point-to-point connection (Standardfestverbindung - SFV). Analogue point-to-point connections allow transmission of a defined frequency spectrum; digital connections are available in bandwidths ranging from a few kilobits to several gigabits.
In addition to limited bandwidth connections, fibre-optic P2Ps are increasingly being offered via so-called dark fibres without limits on usage or bandwidth. The name “dark fibre” stems from the fact that in the case of this point-to-point connection the customer himself is required to provide the “light" for information transfer.
Point-to-point connections use specific interfaces, such as G.703, X.21, Ethernet or others, depending on the type and the medium used. In order to provide point-to-point connections with high availability and low error rates, the connections in the superordinate, actively managed hierarchies can be automatically or manually switched to alternate routes.
Depending on the type, P2Ps can be used for a variety of applications. Computer centres are often interlinked or branch offices connected to headquarters via P2Ps. Telephone systems can also be interlinked using permanent P2Ps. A point-to-point connection to the internet allows cloud telephone systems to be used on a permanent basis.
Carriers often establish connections between various communication services via so-called carrier point-to-point connections (CP2Ps).