Home networks

Broadband for multiple computers

Introduction

Ethernet Networks

Wireless Networks

What is Wifi?

Introduction

Why should you consider a home network?

If you have more than one computer, a network will let all the computers share:

	a single internet connection
	a printer
	files such as images, music, spreadsheets and documents

A network allows you to:

	back up files from one computer to another
	play games that allow multiple users at different computers
	send the output of a device like a DVD player or Webcam to your other computers

So no more squabbles or queuing!

Connecting your computers together creates a network. There are several ways of creating the connections, but essentially you have two options:

Ethernet Networking
Ethernet is easily the most popular networking system available today. It is also one of the widest ranging systems. The equipment needed for an Ethernet-based network can be as simple as two network interface cards (NIC) and a cable, or as complex as routers, bridges and hubs. It is this versatility that makes it so useful to businesses. We will focus on the basics for creating a wired home network and explain all these terms. This is the best and cheapest option if you are able to run cables between computers.

Wireless Networking
In a wireless network, all of the computers in your home broadcast their information to one another using radio signals. This can make networking extremely easy, especially if you have computers all over your house since no cables will be required. It also makes it a whole lot simpler to move computers around. For example, a laptop with a wireless network card is completely portable throughout the house (and garden)! This is a more expensive option, but has complete flexibility without cables running everywhere. This is how to do it.

What You Need for Ethernet

These notes are written for users of Windows 95, 98, Me and XP, but for Mac users, most will be the same.

Ethernet is available in two speeds: 10 Mbps (Megabytes per second) and 100 Mbps, although nowadays you will generally only see things marked and sold as 10/100-Mbps. Most Network Interface Cards (NICs) are capable of operating at either speed. A 10/100-Mbps card costs about £10.

In modern networks NICs are connected using Cat 5 cabling. Cat 5 cabling looks a lot like a telephone cable, comes in several different colours and lengths and has a plug at each end. The plug is called an RJ-45 and looks like the big brother of the RJ-11 plug that goes into your existing dial-up or broadband modem

	RJ-45 Ethernet Network Plug The RJ-45 connector, featuring 8 pins, is the big brother of the RJ-11. It's used for data communications. Cables can be either 'patch' (for normal use between a hub and a computer) or 'crossover' (for use between two hubs or switches).
	RJ-11 Broadband/Telephone Plug The US style RJ-11 plug is a 4 pin version of the RJ-45 pictured below. It is the smallest in size and is used in the UK for ADSL/Broadband Internet connections.

If you have just two computers to connect, then you will require just 2 NICs and a 'crossover' cable. The NIC is plugged into a spare PCI slot within the computer. Your computer will have one or two spare slots in addition to the ones holding your modem and sound card; a laptop computer may have a NIC built-in already or you can buy a plug-in PC card (which does the same job as a NIC) for about £30.

Simply install one NIC in each computer, install the software that comes with them and then plug in the cable to complete the connection. This only works for two computers - to connect more than two you need a hub. Use the 'Network Connections' option in Windows 'Control Panel' to set up your home network.

If you have more than two computers, you run one patch cable from each computer and connect it to a hub at the other end. A basic hub for a home network is a small box that typically costs about £25 (depending on how many connections it can support).

To connect more than two computers using Ethernet, you will need a hub like this.

The hub takes the signal from each computer and sends it to all of the other computers in your home. Hubs come in several sizes, noted by the number of ports available - a four-port hub can connect four computers, an 8-port hub can connect up to eight computers and so on. A broadband/ADSL router (more on these later!) usually has a four-port Ethernet hub built in.

If you don't mind running the cables along the floor, you can install an Ethernet network for two computers in your home for as little as £25 - the cost of 2 network interface cards and a crossover cable. For three computers the cost becomes about £60 - the cost of a hub, three NICs and the cables to connect them. Extra computers would cost an additional £15 each (for the NIC and cable).

Internet Connection Sharing (ICS) software in Windows 98SE onwards lets you share any Internet connection between connected PCs. The downside is that you need to leave the first PC switched on. Connection diagram

A neater solution is to buy a router with a built-in hub that connects to your ISP using the modem, then deliver the Internet data to any connected device - only the router needs to be left switched on. Connection Diagram

What you need for a Wireless Network

This wireless PCI card is inserted inside
your computer to build a wireless network.

With just two computers, while you could simply connect an Ethernet port in each computer with a single cross-over cable, laying the wire itself could be undesirable or even impossible. Wireless networking can connect the two machines without the need for a cable.

Simply equip both machines, be they desktops, notebooks or one of each, with a wireless adaptor and tell the supplied software that it is on an ad-hoc network. The adaptors will then automatically go looking for each other and, so long as they’re within range, your network is finished.

Sharing broadband wirelessly

If you have more than two computers or don’t fancy leaving one switched on just in order to share an Internet connection, then a router and Wireless access point (Wap - more on these later) should form the heart of your network.

A router can automatically share your broadband Internet connection and many models also include a hub with additional network (Ethernet/RJ-45) sockets, allowing you to connect any combination of PCs, Macs, notebooks or even suitably equipped games consoles like the X-box.

Not only will the router allow all connected devices to share your broadband, but the hub will also let them exchange files and share other resources such as printers. Some routers even include built-in ADSL modems from under £100, which is great news for new ADSL/Broadband self-install customers who would have to buy their own modem anyway. For wireless access, simply connect a Wap to the router, or buy a router with a built-in Wap. A well-placed Wap could deliver wireless access throughout an entire home.

One of the most integrated devices around is Netgear’s DG834G which features an ADSL modem, broadband router, four-port Ethernet switch and built-in 802.11g Wap, all for less than £100.

The real advantage of going for a separate Wap, though, is the ability to easily locate it high on a wall or swap it entirely for a faster 802.11 standard in the future. Additionally, since most domestic broadband connections are between 512Kbits/sec and 2Mbits/sec, the 54Mbits/sec theoretical bandwidth of 802.11g is more than sufficient for sharing them wirelessly.

One of 802.11g’s major benefits could also be its Achilles’ heel. Backwards compatibility with 802.11b is built-in, but just one 802.11b device within the system might force an 802.11g network to operate at the slower 11Mbits/sec of the 802.11b standard.

There are several things you can do to maximise the potential range and performance of a wireless network, but the single most effective is ensuring the antennas have as clear a path between them as possible. This can be tricky on the computer side, especially with internal PCI Card adaptors, which might end up keeping your feet company under the desk.

Some cards or adaptors allow antennas to be connected on cables for better positioning on desktops or even higher on walls. If your network uses a wireless access point (Wap) through which all devices connect, the ultimate priority is to position it high in a room, away from obstructions and roughly in the middle of the area of desired coverage.

What is Wifi?

The Wireless Fidelity (WiFi) Alliance was formed in 1999 to offer independent certification of interoperability between 802.11 products. If a product has the WiFi badge, it’s guaranteed to work with other Wifi-certified equipment. At least, that’s the theory: this ‘guarantee’ might not apply outside America.

If you have any network questions, take a look at the Home Networking FAQs

Page last updated Wednesday, 08 December 2004