Point-to-point (telecommunications)

Source: Wikipedia, the free encyclopedia.

In

microwave radio relay
.

The term is also used in

which can connect many communications devices.

Point-to-point is sometimes abbreviated as P2P. This usage of P2P is distinct from P2P meaning peer-to-peer in the context of file sharing networks or other data-sharing protocols between peers.

Basic data link

A traditional point-to-point data link is a communications medium with exactly two endpoints and no data or

packet formatting. The host computers at either end take full responsibility for formatting the data transmitted between them. The connection between the computer and the communications medium was generally implemented through an RS-232
or similar interface. Computers in close proximity may be connected by wires directly between their interface cards.

When connected at a distance, each endpoint would be fitted with a

.

Modern links

UAE
A point-to-point wireless unit with a built-in antenna at Huntington Beach, California

With the exception of

microwave relay link consisting of a transmitter which transmits a narrow beam of microwaves with a parabolic dish antenna to a second parabolic dish at the receiver. It also includes technologies such as lasers which transmit data modulated on a light beam. These technologies require an unobstructed line of sight between the two points and thus are limited by the visual horizon to distances of about 40 miles (64 km).[a]

Networking

In a

full-duplex
connections.

From the OSI model's layer perspective, both switches and repeater hubs provide point-to-point connections on the physical layer. However, on the data link layer, a repeater hub provides point-to-multipoint connectivity – each frame is forwarded to all nodes – while a switch provides virtual point-to-point connections – each unicast frame is only forwarded to the destination node.

Within many switched telecommunications systems, it is possible to establish a permanent circuit. One example might be a telephone in the lobby of a public building, which is programmed to ring only the number of a telephone dispatcher. "Nailing down" a switched connection saves the cost of running a physical circuit between the two points. The resources in such a connection can be released when no longer needed, for example, a television circuit from a parade route back to the studio.

See also

Notes

  1. ^ The Telecommunications Industry Association's engineering committees develop U.S. standards for point-to-point communications and related cellular tower structures.[1] Online tools help users find if they have such line of sight.[2]

References

  1. ^ "TR-14 | Structural Standards for Communication and Small Wind Turbine Support Structures". Telecommunications Industry Association. Archived from the original on 2014-01-07. Retrieved 2011-11-20.
  2. ^ "PtP Estimator Overview". AlphiMAX. Retrieved August 29, 2011.