In telecommunications, the term gateway has the following meaning:
In a communications network, a network node equipped for interfacing with another network that uses different protocols
A gateway may contain devices such as protocol translators, impedance matching devices, rate converters, fault isolators, or signal translators as necessary to provide system interoperability.
It also requires the establishment of mutually acceptable administrative procedures between both networks.
A protocol translation/mapping gateway interconnects networks with different network protocol technologies by performing the required protocol conversions.
Loosely, a computer is configured to perform the tasks of a gateway. For a specific case, see default gateway.
Routers exemplify special cases of gateways.
Gateways, also called protocol converters, can operate at any layer of the OSI model. The job of a gateway is much more complex than that of a router or switch. Typically, a gateway must convert one protocol stack into another.
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