Docking stations and port replicators provide a simplified way of "plugging-in" a portable laptop computer to common computer peripherals. The use of a docking station quickly enables a laptop computer to become a substitute for a desktop computer, without sacrificing the mobile computing functionality of the machine.

Technology

Portable computers can dock and undock hot, cold or standby, depending on the capabilities of the system. In a cold dock or undock, one completely shuts the computer down before docking/undocking. In a hot dock or undock, the computer remains running when docked/undocked. An intermediate style used in some designs allows the computer to be docked/undocked while powered on, but requires that it be placed into a sleep mode prior to docking/undocking.

Docking stations can be broadly split up into four basic varieties.

Port replicator

Port replicators (also called passthroughs) are functionally indistinguishable to a bundle of extension cables, except that they can be plugged in and unplugged all at once, saving time. Some also include simple electrical adapters to change from one pinout to another (e.g., Micro-DVI to normal DVI connector.) An example would be the BookEndz Macintosh docks.

Breakout dock

Main article: breakout box

This design not only replicates externally visible ports, but offers extra ones. While sometimes done using electrical adapters and splitters on a standard port, this is most often done using a proprietary connector that consolidates the signals from many concealed traces from onboard external busses into one connector, reducing the number of ports on the computer while still allowing cheap and convenient access to whatever features its motherboard may possess.

Most companies that produce laptops with such breakout ports also offer simpler adapters that grant access to one or two of the busses consolidated in them at a time.

Converter dock

Similar to a breakout device, some docking stations produce multiple connections from one port, only instead of extracting them from internal chipsets, they create them inside the dock using converters. Typically USB-based, they incorporate a range of converters such as USB display adapters, audio chipsets, NICs, storage enclosures, modems and memory card readers connected through an internal USB hub to give the host computer access to extra connections it did not previously possess. Simpler “docking stations” consist of nothing more than a hub inside a stand.

As they tend to use non-proprietary connections, converter docks are typically vendor neutral and supplied by third parties.

Hybrid dock

By connecting directly to the motherboard's chipset bus like a daughterboard of sorts, a hybrid dock allows a portable computer to effectively convert into a desktop machine. Like many breakout boxes it uses a proprietary connector, but to communicate with devices that are normally internal.

The Duo Dock allowed a laptop to access not only extra ports and drives, but slots and sockets for extra expansion cards, RAM, VRAM, coprocessors and CPU cache to work alongside the computer's internal components.

Desktop docking stations

A desktop docking station is an accessory for a portable computer. The docking station normally remains on a desk and contains or connects to hardware not needed while traveling. This enables the core portable device to be detached providing a lighter laptop. Docking stations often complement a light-weight ultraportable so that it can function more like a desktop replacement computer, in use at home, for example.

Many newer desktop docking station designs are primarily intended to use the computer's own screen in lieu of an external monitor as the primary display. These docking stations are sometimes referred to as laptop stands.An Oysterdock desktop docking station

Mobile docking stations

A Kodiak mobile docking-station

Mobile docking stations operate in vehicles. Many industries have adopted mobile computing and hence wish to have their vehicles fully equipped as mobile field-offices. Some of the industries currently using mobile docking stations include (for example): law-enforcement, electricity, telcos, military, EMS, fire, construction, insurance, real-estate, agriculture, oil, gas, transportation, warehousing, food-distribution, surveying, and landscape companies.

Some mobile docking stations withstand the rigors of travel and have MIL-STD 810E construction-specifications for vibration and impact.