what is network switch

8/2/2019 What is Network Switch

1/13

What is Network Switch - How

switches Works - Uses - Types of Switches

Network SwitchesIn the terminology of electronics, switch is an electronic device which breaks the circuit and thus

carries the current to different conducts. Whereas in networking, switches are referred as the

devices which are used to establish or connect a network.

Role of network switches

Large and small LAN networks require a bundle ofswitches for the network

connectivity. Various kinds of switches such as packet switches and network switches

are an integral part of the network. The purpose of switches is connect all kinds ofwhether traditional LAN s or SOHO networks. SOHO is a term given to a very small

enterprise comprising of more than or equal to ten people. The requirement of such

small networks is a single all purpose switch. This single switch serves the purpose of

connecting to DSL, WiFi and cable router. Typically switches operate at the data link

layer of the OSI model. Switches can operate at different OSI layers, and these multi

layered devices are called multi layer switches. Multi layer switches can operate at

data link layer, physical layer, transport and network layer. Switches are of many

types and they contain many ports. The presence of ports helps to connect or

maintain various networks as Fiber Channel, ATM and most commonly Ethernet. Layer

3 or the network layer of the OSI model is help switches to connect to the network

and process data. Network Switches are helpful in establishing all kinds of small

and large networks. For example in a large organization where there is a need to

connect various LANs to form one big WAN. The WAN router is often connected

through the switches.

Micro segmentation using network switches

Switches are dedicated, active and smart devices they work much more efficiently

than the other network devices. Switches are used to build micro segments in the

network. The purpose ofsegmentation is to abstain from the data and connections

to overlap each other. For example you establish a network connecting five or six

computers to each other as a, b, c, d, e. all these terminals are connected using five

switch port. Terminals such as a and b can transfer data to each other as well as

other 3 terminals without intermingling with each other. This efficiency and

unambiguous working of the network is due to the efficacy ofnetwork switches. If

we however connect our network with the hub alone, all terminals will share single

working unit hub. There would be chance of these devices to collide. Moreover the
http://www.freewimaxinfo.com/network-switches.htmlhttp://www.freewimaxinfo.com/local-area-network-lan.htmlhttp://www.freewimaxinfo.com/wide-area-network-wan.htmlhttp://www.freewimaxinfo.com/network-switches.htmlhttp://www.freewimaxinfo.com/network-switches.htmlhttp://www.freewimaxinfo.com/network-switches.htmlhttp://www.freewimaxinfo.com/local-area-network-lan.htmlhttp://www.freewimaxinfo.com/wide-area-network-wan.htmlhttp://www.freewimaxinfo.com/network-switches.html


2/13

segmentation that the use of switches provides is helpful in attaining the full duplex

connection.

Types and uses of switches

The network switches serve innumerable purposes and uses. They are a reliable and

efficient way to establish connectivity. Switches are of many types depending on

the prototype in which they are used. The various categories of switches contained in

a network are unmanaged switches, managed switches. The least expansive

switches , that are used for single connection and small network operations is called

unmanaged switches. They are termed so because of their lack of configuration

crossing point. When the operation of the switches can be modified to perform

various operations, they are termed as managed switches. Managed switches are

preferred due to their adaptive configuration. Managed switches can create virtual

LANs and can also be used to alter the connection speed. Managed switches arefurther dived into two categories such as smart switches and enterprise managed

switches. The switches which have minimum management capability are called smart

switches. Whereas the switches, which can provide full line and web interface are

called enterprise switches. Enterprise switches are expense but they can be

customized for many uses.

What is a Switch?

A switch is used in a wired network to connect Ethernet cables from a number of

devices together. The switch allows each device to talk to the others. Switches aren't

used in networks with only wireless connections, since network devices such as

routers and adapters communicate directly with one another, with nothing in

between.

Although you can use the ports on the back of a router or modem to connect a few

Ethernet devices together, depending on the model, switches have a number of

advantages:

Switches allow dozens of devices to connect.

Switches keep traffic between two devices from getting in the way of yourother devices using the same network.

Switches allow control of who has access to various parts of the network. Switches allow you to monitor usage.

Switches allow communication (within your network) that's even faster thanthe Internet.

High-end switches have pluggable modules to tailor them to network needs.

Switches targeted for home uses, or for small businesses are described here.
http://www.freewimaxinfo.com/network-switches.htmlhttp://www.netgear.com/Products/Switches/DesktopSwitches.aspxhttp://www.freewimaxinfo.com/network-switches.htmlhttp://www.netgear.com/Products/Switches/DesktopSwitches.aspx


3/13

Switches targeted for larger networks, medium to large businesses are described

here. Due to their complexity, unlike with other NETGEAR products, Layer 3 Managed

Switches one of the available types of business switches do not have any free

support.

SwitchesSwitch Contacts - pole, throw etc.

Standard Switches- SPST, SPDT, DPST, DPDT.

Special Switches - multiway, key, tilt, reed etc.

Also see: Relays | Series and Parallel Connections - Switches

Circuit symbol for a

simple on-off switch

Selecting a Switch

There are three important features to consider when selecting a switch:

Contacts (e.g. single pole, double throw)

Ratings (maximum voltage and current)

Method of Operation (toggle, slide, key etc.)

Switch Contacts

Several terms are used to describe switch contacts:

Pole - number of switch contact sets.

Throw - number of conducting positions, single or double.

Way - number of conducting positions, three or more.

Momentary - switch returns to its normal position when released.

Open - off position, contacts not conducting. Closed - on position, contacts conducting, there may be several on positions.

For example: the simplest on-off switch has one set of contacts (single pole) and one

switching position which conducts (single throw). The switch mechanism has two

positions: open (off) and closed (on), but it is called 'single throw' because only one

position conducts.
http://www.netgear.com/Products/Switches.aspx?for=Business+Networkinghttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/relay.htmhttp://www.kpsec.freeuk.com/seriespa.htmhttp://www.netgear.com/Products/Switches.aspx?for=Business+Networkinghttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/switch.htmhttp://www.kpsec.freeuk.com/components/relay.htmhttp://www.kpsec.freeuk.com/seriespa.htm


4/13

Switch Contact Ratings

Switch contacts are rated with a maximum voltage and current, and there may be

different ratings for AC and DC. The AC values are higher because the current falls to

zero many times each second and an arc is less likely to form across the switch

contacts.

For low voltage electronics projects the voltage rating will not matter, but you may

need to check the current rating. The maximum current is less for inductive loads

(coils and motors) because they cause more sparking at the contacts when switched

off.

Standard Switches

Type of Switch Circuit Symbol Example

ON-OFFSingle Pole, Single Throw = SPST

A simple on-off switch. This type can be

used to switch the power supply to a

circuit.

When used with mains electricity this

type of switch mustbe in the live wire,

but it is better to use a DPST switch to

isolate both live and neutral.

Photograph Rapid Electronics

SPST toggle switch

(ON)-OFFPush-to-make = SPST Momentary

A push-to-make switch returns to its

normally open (off) position when you

release the button, this is shown by the

brackets around ON. This is the standard

doorbell switch.


Push-to-make switch

ON-(OFF)Push-to-break = SPST Momentary

A push-to-break switch returns to its

normally closed (on) position when you
http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/


5/13

release the button.

Photograph Rapid ElectronicsPush-to-break switch

ON-ON

Single Pole, Double Throw = SPDT

This switch can be on in both positions,

switching on a separate device in each

case. It is often called a changeover

switch. For example, a SPDT switch can

be used to switch on a red lamp in one

position and a green lamp in the other

position.

A SPDT toggle switch may be used as a

simple on-off switch by connecting to COMand one of the A or B terminals shown in the

diagram. A and B are interchangeable so

switches are usually not labelled.

ON-OFF-ONSPDT Centre Off

A special version of the standard SPDT

switch. It has a third switching position

in the centre which is off. Momentary

(ON)-OFF-(ON) versions are also

available where the switch returns to thecentral off position when released.

Photographs Rapid Electronics

SPDT toggle switch

SPDT slide switch

(PCB mounting)

SPDT rocker switch

Dual ON-OFFDouble Pole, Single Throw = DPST

A pair of on-off switches which operate

together (shown by the dotted line in

the circuit symbol).

A DPST switch is often used to switch

mains electricity because it can isolate

both the live and neutral connections.


DPST rocker switch
http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/


6/13

Dual ON-ONDouble Pole, Double Throw = DPDT

A pair of on-on switches which operate

together (shown by the dotted line in

the circuit symbol).

A DPDT switch can be wired up as a

reversing switch for a motor as shown

in the diagram.

ON-OFF-ONDPDT Centre Off

A special version of the standard SPDT

switch. It has a third switching position

in the centre which is off. This can be

very useful for motor control becauseyou have forward, off and reverse

positions. Momentary (ON)-OFF-(ON)

versions are also available where the

switch returns to the central off position

when released.


DPDT slide switch

Wiring for Reversing

Switch

Rapid Electronics stock a wide range of switches and

they have kindly allowed me to use their photographs on this page. The photographs

are from their Image Gallery CD-ROM.

Special Switches

Type of Switch Example
http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/


7/13

Push-Push Switch (e.g. SPST = ON-OFF)

This looks like a momentary action push switch but it is a

standard on-off switch: push once to switch on, push

again to switch off. This is called a latching action.


Microswitch (usually SPDT = ON-ON)

Microswitches are designed to switch fully open or closed

in response to small movements. They are available with

levers and rollers attached.


Keyswitch

A key operated switch. The example shown is SPST.


Tilt Switch (SPST)

Tilt switches contain a conductive liquid and when tiltedthis bridges the contacts inside, closing the switch. They

can be used as a sensor to detect the position of an

object. Some tilt switches contain mercury which is

poisonous.


Reed Switch (usually SPST)

The contacts of a reed switch are closed by bringing a

small magnet near the switch. They are used in securitycircuits, for example to check that doors are closed.

Standard reed switches are SPST (simple on-off) but SPDT

(changeover) versions are also available.

Warning: reed switches have a glass body which is easily

broken! For advice on handling please see the

Electronics in Meccano website.
http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.eleinmec.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.eleinmec.com/


8/13


DIP Switch (DIP = Dual In-line Parallel)

This is a set of miniature SPST on-off switches, the

example shown has 8 switches. The package is the samesize as a standard DIL (Dual In-Line) integrated circuit.

This type of switch is used to set up circuits, e.g. setting

the code of a remote control.


Multi-pole Switch

The picture shows a 6-pole double throw switch, also

known as a 6-pole changeover switch. It can be set tohave momentary or latching action. Latching action

means it behaves as a push-push switch, push once for

the first position, push again for the second position etc.


Multi-way Switch

Multi-way switches have 3 or more conducting positions.

They may have several poles (contact sets). A popular

type has a rotary action and it is available with a range ofcontact arrangements from 1-pole 12-way to 4-pole 3 way.

The number of ways (switch positions) may be reduced by

adjusting a stop under the fixing nut. For example if you need a

2-pole 5-way switch you can buy the 2-pole 6-way version and

adjust the stop.

Contrast this multi-way switch (many switch positions) with the

multi-pole switch (many contact sets) described above.


Multi-way rotary switch

1-pole 4-way switch symbol

Switches

Switches are electronic components which are used to break electrical circuits,

interrupting the current or diverting it from one conductor to another. They can

control the flow of power within a device, domestic circuit or appliance, and switches
http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/http://www.rapidonline.com/


9/13

are found in all manually or automatically operated circuits. Rapid stocks a

comprehensive range of industrial switches, such as control unit switches, edge

switches, DIL switches, key and keyboard operated switches, latching PCB switches,

microswitches, push-button switches, rotary, toggle, slide and tactile switches.

Products from the industrys leading manufacturers, SCI, Bulgin and Camden Boss. If

you are looking for high quality switches for your application requirements and we donot have what you need today, we may be able to source these components for you.

Please contact us for details.

Switches

Control Unit Switches

(11)

DIL Switches

(41)
http://www.rapidonline.com/Electronic-Components/Switches/Control-Unit-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Control-Unit-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/DIL-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/DIL-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Control-Unit-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Control-Unit-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/DIL-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/DIL-Switches


10/13

Edge Switches

(7)

Key Operated Switches

(16)

Keyboard Switches

(13)
http://www.rapidonline.com/Electronic-Components/Switches/Edge-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Edge-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Key-Operated-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Key-Operated-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Keyboard-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Keyboard-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Edge-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Edge-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Key-Operated-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Key-Operated-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Keyboard-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Keyboard-Switches


11/13

Keypads

(43)

Latching PCB Switches

(28)

Microswitches

(57)
http://www.rapidonline.com/Electronic-Components/Switches/Keypadshttp://www.rapidonline.com/Electronic-Components/Switches/Keypadshttp://www.rapidonline.com/Electronic-Components/Switches/Latching-PCB-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Latching-PCB-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Microswitcheshttp://www.rapidonline.com/Electronic-Components/Switches/Microswitcheshttp://www.rapidonline.com/Electronic-Components/Switches/Keypadshttp://www.rapidonline.com/Electronic-Components/Switches/Keypadshttp://www.rapidonline.com/Electronic-Components/Switches/Latching-PCB-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Latching-PCB-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Microswitcheshttp://www.rapidonline.com/Electronic-Components/Switches/Microswitches


12/13

Push-Button Switches

(125)

Rocker Switches

(37)

Rotary Switches

(17)
http://www.rapidonline.com/Electronic-Components/Switches/Push-Button-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Push-Button-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rocker-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rocker-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rotary-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rotary-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Push-Button-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Push-Button-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rocker-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rocker-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rotary-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Rotary-Switches


13/13

Slide Switches

(16)

Tactile Switches

(111)

Toggle Switches

(64)
http://www.rapidonline.com/Electronic-Components/Switches/Slide-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Slide-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Tactile-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Tactile-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Toggle-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Toggle-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Slide-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Slide-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Tactile-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Tactile-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Toggle-Switcheshttp://www.rapidonline.com/Electronic-Components/Switches/Toggle-Switches

what is network switch

Documents