Physical Layer Ports - Types and Description of Ports

Physical Layer Ports

Physical Layer Ports are the medium which are used to connect different peripheral devices with the computer such as printer, mouse, keyboard, scanner, usb, monitor and many more.

On physical layer, ports are made on a piece of equipment with specific shapes. in now a days, modern computers have some specific ports on them which are USB, VGA, Ethernet, IEEE 1394, DVI and TRS physical ports. But most commonly used ports by industrial and professionals are Serial, Parallel, PS/2 and USB.

Physical Shape of Ports

Physical Layer Ports have both male and female connectors but male connectors are most common in use. Bent pins are easy to replace form the cable that why female connectors are used at the fixed part of the interface.

Ports are of different shapes which are as: round (PS/2), rectangular (FireWire), square (Telephone, Ethernet) and many more.

Electrical Signal Transfer

In electrical all the physical ports are divided into two categories: Serial and Parallel

• Serial ports can send and receive only one bit at a time using single pair of wire.
• Parallel ports can send and receive multiple signals at a time using multiple pair of wires.

When ports are connected with each other they perform handshaking which means that they share their transfer type, transfer rate and all other necessary information before the data is sent.

In 2006, manufacturers have standardized the colors which are associated with ports on personal computers.

1. Orange, Purple and Grey used for Keyboard PS/2
2. Green used for Mouse PS/2
3. Magenta and Blue used for Parallel Printer DB-25
4. Amber used for Serial DB-29 or DB-9
5. Pastel Pink used for Microphone 1/8" stereo (TRS) mini-jack
6. Pastel Green used for Speaker 1/8" stereo (TRS) mini-jack

Different Types of Port and their description

Digital Virtual Interface (DVI) is a interface used for video display and it is developed by Digital Display Working Group (DDWG). it is used to connect different display devices with computer such as monitor, LCD, LED and many more.

Display Port is a digital display interface which is developed by Video Electronics Standards Association (VESA). It is used to connect display device with the computer such as monitor and it is also used to carry audio, usb and all other form of data.

IEEE 1394 Interface (Firewire) is used for high communication and to transfer real time data. It was developed by Apple late in 1980's and named it FireWire.

PS/2 Connector is used to connect mouse and keyboard with the computer and it contains 6-pins and have round shape. PS/2 stands for Personal Computer/2 which comes form IBM.

Serial Ports are used to connect old age monitors and printers. It can transfer only one bit at a time using single pair of wire.

VGA Connector VGA stand for Video Graphic Adopter which is used in now a days to connect modern video output devices. The connector of VGA is DE-15. It has 15 pins having 3 rows and each row has 5 pins. DE-15 is also know as RGB Connector, D-sub 15, mini sub D-15, mini D-15, DB-15, HDB-15, HD-15.