Direct connection

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A direct connection in information and communication technology (ICT) is a direct, immediate connection between two points or locations. The synonymous technical term Point-to-Point [-Connection] comes from English - in German : Point-to-Point [ connection ] (abbreviation PP or PTP ). The expression “ from A to B ” is also used colloquially (see A and B participants ).

Topologically , a distinction is made between:

  1. Point -to-Point in the real sense - that is, the connection route without any intermediate station. B. the communication in the lower network layers = layers 1–3 in the OSI model (→  7-layer model ); Example: (direct) communication between computer and peripheral device ] → corresponds to unicast as addressing type ;
  2. End-to-end ( end -to-end ) or multihop - a PTP path with intermediate stations [on the higher network layers = layers 4–7 in the OSI model; Example: Internet , LAN with router ] → also corresponds to unicast ; and
  3. Point-to-Multipoint ( point-to-multipoint ), abbreviation PTMP - a star topology [ eg: television ] → corresponds to multicast / broadcast or downlink .

Depending on whether there are higher-level instances in the way of establishing a direct connection between two participants , one speaks either

Typical application examples:

  • In communication technology , it is a connection that also occurs on the telephone . If two people are on the phone, it is a direct connection. During the call, one line in the network is reserved only for the two call partners (→  line switching ).
  • With ISDN , a distinction is made between PTP and PTMP. When testing an ISDN connection, depending on the type of connection, you must always switch between PTMP (for a basic connection ) and PTP (for systems or primary rate connection ) in the test device .
  • The tunnels , a method, direct build within other connection systems.


  • Klaus Dembowski: Local Networks. Handbook of complete network technology, Addison-Wesley Verlag, Munich 2007, ISBN 978-3-8273-2573-0 .
  • Stefan Blumhagel, Thomas Joos: Networks - secret tricks. Markt + Technik Verlag, Munich 2005, ISBN 3-8272-6803-6 .

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