Which device connects multiple computers together in a lan?

Computer network consists of different devices such as router, hub, switch and others. Without these network devices data cannot be transmitted from one computer to another in a LAN or WAN network. These devices link up all the local and remote network segments with each other to make data communication from one segment to another. The two important devices of a big network are routers and switches. A computer network with good infrastructure with properly placed and configured network devices such as routers, switches etc. are helpful in reducing the overall operational cost, improve the performance, manageability and reliability.

6.3.1 Repeater:

A repeater is a network device that is used to retransmit the weaker signals in a network. A repeater receives the signals on the electromagnetic or optical transmission mediums. Repeater removes the unwanted noise from the incoming signals. A series of the repeaters is used to amplify the signals in the big network. The can also relay the messages between sub networks that use different protocols. Repeaters work at physical layer.

A hub is a networking device, which is used to connect the two segments of a wired network. In star topology, every computer is directly connected with the hub. In case of any fault in the hub, the data communication in the network computers stops. In an Ethernet (bus)-based networked a hub is a central device that is used to connect all the computers with each other.

A hub has multiple ports such as 4, 6, 8, 16 and 24 etc. when data packets are reached at hub. They are broadcasted to all the computers unlike a switch and only the destined computer receives the data. When you want to connect more than two computers with each other a hub or switch is required in a local area network. Hubs operate at the physical layer.

6.3.3 Switch:

A network switch performs the same functionality in a network as a hub expect a different that switch does not broadcast the data packets o all the computers in a network like a hub. A network switch has multiple ports like 4, 8, 16 and 24 etc. All the computers in a wired network are directly connected with the switch through Ethernet cable. Switches limit the traffic to and from each port and all the devices connected to the switch has maximum available bandwidth. Switch doesn’t provide the built-in firewall capabilities like the routers. In the telecommunication and packet switched infrastructure switches play an important role. They transmit the data towards its destination based on the IP address. Switches work at data link layer.

6.3.4 Network Interface Card:

A network interface card is used to connect a computer to an Ethernet network. The card(shown in the figure below) provides an interface to the media. This may be either using an external transceiver mounted on the network interface card PCB. The card usually also contains the protocol firmware and Ethernet Controller needed to support the Medium Access Control (MAC) data link protocol used by Ethernet.

There is also a page showing examples of various types of networking equipment, include NICs for Ethernet.

9.3.5 Routers:

A router is a network communication device that is used to connect two or more logically and physically different networks. A router can be used to connect a LAN to LAN, LAN to WAN and LAN to internet. A router acts as a post office where sorting and distribution of the posts (packets in case of routers) is done. A router works on the basis of an IP address. Every router has built-in Operating System known as IOS. A router works on the network layer of the OS model and it routes the data towards the optimal path. Router uses the header information of the packets and forwarding table to define the best shortest possible path of the data.

6.3.6 Modem:

A modem is communication device that performs two different functions such as modulation i.e., it converts the digital data into analog and analog into digital. The faster types of the modems are used by the internet such as DSL modem and optical modems.

Internal modem:

A modem that resides on an expansion board that plugs into a computer.

External modem:

An external modem is a box that attaches to a computer’s COM port via cables.

ADSL modem:

ADSL stands for Asymmetric Digital Subscriber Line. It is a technology that allows copper telephone pairs to be used to provide a broadband connection. It provides ‘always-on’ Internet connection that is automatically established once the PC and ADSL modem are switched on.

Always-on means that the ADL broadband sets up a permanent connection to the internet that lets you access the internet as soon as you switch on the computer and the modem. You do not need to dial up like when you are using a standard modem connection. There will be no call charges for internet access but voice calls will be charged as before.

Connect both computers with one cable, such as an Ethernet crossover or special-purpose USB cable.
Or, connect the PCs through a central infrastructure, such as an Ethernet or USB hub. Two cables are required.
For newer computers and laptops, connect wirelessly via Wi-Fi, Bluetooth, or infrared. Wi-Fi is preferred.

This article explains how to connect two computers to one home network. You can use this kind of network to share files, a printer or another peripheral device, and an internet connection.

Lifewire / Maddy Price

The conventional way to network two computers involves making a dedicated link by plugging one cable into the two systems. You may need an Ethernet crossover cable, a null modem serial cable or parallel peripheral cable, or special-purpose USB cables.

The Ethernet method is the preferred choice because it supports a reliable, high-speed connection with minimal configuration required. Also, Ethernet technology offers the most general-purpose solution, allowing networks with more than two computers to be built later.

If one of your computers possesses an Ethernet adapter, but the other has a USB, an Ethernet crossover cable can be used by first plugging a USB-to-Ethernet converter unit into the computer's USB port.

This type of cabling, called Direct Cable Connection in Microsoft Windows, offers lower performance but the same basic functionality as Ethernet cables. You may prefer this option if you have Ethernet cables readily available, and network speed is not a concern. Serial and parallel cables are never used to network more than two computers.

Ordinary USB 2.0 or newer cables with Type-A connectors can connect two computers directly to each other. You may prefer this option over others if your computers lack functional Ethernet network adapters.

Dedicated connections with Ethernet, USB, serial, or parallel cables requires that:

Each computer has a functioning network interface with an external jack for the cable.
The network settings on each computer are appropriately configured.

One phone line or power cord cannot be used to directly connect two computers for networking.

Rather than cable two computers directly, the computers can be joined indirectly through a central network fixture. This method requires two network cables, one connecting each computer to the fixture. Several types of fixtures exist for home networking:

Implementing this method often entails an additional up-front cost to purchase more cables and network infrastructure. However, it's a general-purpose solution that accommodates any reasonable number of devices (for example, ten or more). You will likely prefer this approach if you intend to expand your network in the future.

Most cabled networks use Ethernet technology. Alternatively, USB hubs work well, while powerline and phoneline home networks offer a unique form of central infrastructure. The standard Ethernet solutions are generally reliable and offer high performance.

In recent years, wireless solutions have increased in popularity for home networking. As with cabled solutions, several wireless technologies exist to support basic two-computer networks.

Wi-Fi connections can reach a greater distance than wireless alternatives. Many newer computers, especially laptops, contain built-in Wi-Fi capability, making it the preferred choice in most situations. Wi-Fi can be used either with or without a network fixture. With two computers, Wi-Fi networking minus a fixture (also called ad hoc mode) is simple to set up.

Bluetooth technology supports reasonably high-speed wireless connections between two computers without the need for a network fixture. Bluetooth is commonly used when networking a computer with a consumer handheld device like a cellphone.

Most desktop and older computers do not possess Bluetooth capability. Bluetooth works best if both devices are in the same room in close proximity to each other. Consider Bluetooth if you have an interest in networking with handheld devices and your computers lack Wi-Fi capability.

Infrared networking existed on laptops years before either Wi-Fi or Bluetooth technologies became popular. Infrared connections work between two computers, do not require a fixture, and are reasonably fast. Being simple to set up and use, consider infrared if your computers support it, and you don't want to invest the effort in Wi-Fi or Bluetooth.

If you find mention of an alternative wireless technology called HomeRF, you can safely ignore it. HomeRF technology became obsolete several years ago and is not a practical option for home networking.

FAQ

How do I connect two computers to a single monitor?

One of the simpler ways to share a monitor between two computers is with software like Microsoft Remote Desktop, though remote connections do sometimes include drawbacks like display lag and pixelation. Many modern monitors also offer more than one port for video input, so you can physically connect both machines to a single screen. The drawback in this case being that you'll also need to manually change the monitor's internal input selection settings every time you want to switch.
How do I connect two computers to one printer?

If both computers are already sharing the same network, giving them both access to the same printer is easy. Make sure the printer is connected to your main PC, then open Control Panel and select Hardware and Sound > View devices and printers. Right-click on the printer you want to share and select Printer properties > Sharing, then select Share this printer. Now other PCs on your network will be able to find it and connect.