Definition of Switch
Switch is
an adjective used to describe what it commutes : replace,
modify, replace or change something. As a noun, the idea of a switch can
refer to different devices.
A switch can
be a device that allows an electric current to change conductor .
To
accomplish this goal, the switch makes the electrons follow a
different path.
The
operation of these switches is similar to that of the switches . While
the switches are responsible for the disconnection of an electrical circuit,
the switches cause the
current to pass to another conductor to
connect a different circuit. In the field of
telephony , a switch is called to the machine that is responsible
for connecting different telephone lines.
Also known as a switchboard ,
the switch allows two points to be linked by different nodes. In other
words, the switch determines the path established by the
communication between
two users, leaving said path "occupied" until the
communication in question ends.
Switching in
the context of a telephony network is not a simple action, but is made up of
different stages , and all of them must be successful for
communication to take place. First, there is the connection request ,
which must be approved to proceed to the call establishment ; then
the stage begins in which the data transfer between the different
nodes takes place; finally, the connection release must be
executed .
Let's see
some of the advantages of using a switch for telephone communication:
* the
transmission is carried out in real time , something indispensable
for this type of communication. At present, it is possible
to establish a connection to transmit data
audio and video in
real time, something that we see in so -called video calls ;
* throughout
each session, the nodes that participate in the communication have exclusive
access to the resources, and this guarantees an acceptable level of quality;
* There
is no containment . This means that since the circuit is established,
the nodes can transmit the data at the maximum speed allowed by the medium, and
they should not share the time of use nor the bandwidth; * Once
the circuit is established it is not necessary to spend time
calculating and routing those nodes that are among the main ones, since the
switch allocates a specific physical circuit to each communication
session. In this way, the intermediate nodes receive a single route for
the packets, both for incoming and outgoing ones.
Of course,
the switch also has certain disadvantages, such as the following: * the
beginning of the communication is not immediate, since it is necessary to
dedicate some time to the first stages, so that it is not possible to
transmit the data until they have been overcome; * while
the parties are not using the resources that have been assigned to them, they
are wasted; * the
communication route is fixed and this prevents it from being readjusted
according to the needs of each connection; * If an
intermediate node has a fault, the entire circuit falls and it is necessary to
start the process again.
For computers ,
a switch is a digital logic element used to interconnect different sections of
the network. The switches carry the data from one segment to another
according to the destination MAC address of the different frames
existing in the
network.
Thanks to a
switch of this type, various sections of a network can be
connected to be merged. Because they only transmit the data to the
segments in which there is a recipient, they allow improving the security and
performance of the so-called local area networks.
