Hub

A HUB is the standard way to link computers on a small network. All the computers are plugged into it in a 'star' configuration with the hub in the middle.

Hubs are quite simple and dumb. Each packet of information received is broadcast to all the computers on the network, it's up to the network card in the computer to decide if the data is intended for it.

That's OK on a small network but as the traffic gets greater it can become very wasteful to send data to places it doesn't need to go. With big files being moved through the hub there can be congestion and slower transfer speeds.

Enter the SWITCH.

Switches are much smarter, they know what computers are connected and act more like a traffic cop. Each packet of information received is analyzed to see where it's supposed to go and then forwarded to that specific computer. Network capacity isn't wasted sending data to places it isn't wanted. A modern unmanaged switch does all the work without human intervention. Like a hub you just plug it in.

For most of us you won't be able to tell any difference in speed between a hub and a router. Your computers can't push data out fast enough to cause significant blockages at a hub. In addition your Internet connection is much slower than even a standard 10Mbps network.

So it's not worth paying the extra money for a switch to use in a home or small office. A few months ago I would have said that a hub was the most economical option, but that's changed.

These days switches can be the same price or even cheaper than a hub. Linksys has a 5 port 10/100 Mbps hub for a list price of US$59 while their equivalent switch is listed for $50. You can get both for less in stores.

So what's a router? In short it's really smart switch that lets you connect one network (one at home or office) with another network (the Internet). A router lets you connect multiple computers to a single net connection and works out what information (web pages, email etc) goes to each local computer.

A router makes your small network appear like a single computer to the rest of the Internet with tricks like Network Address Translation (NAT).

These days it's common to combine the modem (phone, cable or ADSL) with a router into a single box. That's cheaper and more efficient. You can also get a hub or switch combined with the router.

As security becomes more important you can and should get a router with a firewall. A firewall will attempt to stop unwanted attempts to hack into your computers from around the Internet. Having a firewall is a good idea but it isn't the total solution and you should take other steps to make sure your computers are secure (topic for another Helper?).

One important thing to look for in a router is "Universal Plug 'n Play" (UPnP) capability. Most routers still don't have it but trust me, you'll want it.

A dirty little secret of Windows Messenger is that audio/video conversations plus file transfers won't work with a traditional router. Or rather you can make them work but it's very complicated and requires exposing many ports to the Internet which compromises your network safety.

The solution is a UPnP router, these negotiate with Windows XP to make available the necessary links to the Internet as required. As the Internet finds more uses, especially with streaming video and audio, combined with more security concerns I think that UPnP will become much more useful. Best to get a UPnP router and save yourself hassles down the line.

Mind you there's an anti-UPnP lobby with some security concerns too. I'd still suggest getting a UPnP router, despite the legitimate concerns, but turn the feature off unless you need it.

Cable

Time was you could pick up a cable with RJ45 connectors and be ready to go but now there's Cat 5, 5e and even 6. Here's an explanation of which one will suit you.

This guide is intended for home and small office users. If you have a large office to cable then you should get professional advice.

Standard network cable these days is called Category 5 (aka 'cat 5') - it's good for any 10 or 100Mbps network which is what virtually everyone runs at home or in offices.

As faster network standards come along a better network cable was needed. Category 5e (enhanced) is basically the same cable design but made to a higher quality standard. Cat 5e can handle the up-and-coming Gigabit (1,000Mbps) networks.

Gigabit network hubs, switches and adapters are available but are generally still too expensive for most of us. The main current use is from a server to network hub/switch to reduce that bottleneck. But in years to come I expect Gigabit hardware to come down in price and be more common.

You may see Category 6 cables on sale usually for a hefty premium. Cat 6 cables are yet another quality improvement from Cat 5 and 5e. When 10,000Mbps (10 Gigabit) networks become available Cat 6 cables will be able to handle it.

========

Compare these :

Hub -- Layer 1 network device -- sends packets to all ports.
Switch -- Layer 2 network device -- sends packets to each machine based on the MAC address.
Router -- Layer 3 network device -- sends packets to each machine based on the MAC address and IP.
Gateway -- Layer 4~7 network device or server -- sends packets to each machine based on the MAC address, or protocol also can translate other protocols.