Get help with real-world Wi-Fi hassles, from dead spots and security threats to media-streaming hiccups

Networks are fantastic when they hum along behind the scenes, but all too often they fail. When your printer disappears or your Skype calls break up every time your partner watches YouTube, it's time to get your geek on and learn what makes your network tick.

Here, then, are some tried-and-tested strategies – as well as some new tricks for wireless veterans – to help you make your network behave.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

Nail the basics

By far the most common network problems involve disappearing internet connections, printers and PCs. Lost connections can generally be solved by rebooting your broadband modem, network router or computer. But if you have to do this repeatedly, your router and PC settings are probably the culprits.

Start by extending to at least a week your router's DHCP (dynamic host configuration protocol) lease time – the time the router reserves an IP address for a device on the network. You can access this setting via
your router's browser-based firmware.

If disconnects are affecting a laptop, check the power-management setting for its network adaptor. In Windows XP, right-click My Computer, then select Properties. Go to the Hardware tab and click Device Manager. In the Network Adapters area, find your adaptor and again select Properties.

Under Power Management, untick the box that turns off the adaptor when power-saving kicks in. Battery life may be slightly reduced but you'll have a stable network connection.

DNS (domain name system) services are another factor that can contribute to lost connections. DNS servers are the PCs on which your ISP stores the databases that it uses to translate individual URLs into their corresponding numerical IP addresses. If you receive messages that web pages can't be found or email can't be retrieved, try using the DNS servers at opendns.com.

Start by accessing the WAN (wide area network) settings in your router's browser-based firmware. Then change the IP addresses for DNS to 208.67.222.222 and 208.67.222.220. OpenDNS is free and it blocks known phishing sites.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

Disappearing printers

If your shared USB printer seems to come and go with a mind of its own, ensure the PC it's attached to isn't hibernating. If possible, connect your printer to a desktop PC rather than a laptop and leave it switched on.

To cut back on power consumption, allow the display to go into sleep mode.

In XP, verify that File and Printer Sharing for Microsoft Networks is installed for all network adaptors. This way, switching between wired and wireless networks won't kill printer sharing. Go to Control Panel, Network Connections and, for each network adaptor, right-click the device and select Properties. If you don't see File and Printer Sharing for Microsoft Networks, click the Install button to add it.

Better yet, set up a print server so you don't have to worry about working through a host PC. Some routers have built-in USB printer ports; standalone print servers plug into your router. If you use a multifunction device for printing, choose a print server that supports scanning, such as D-Link's USB RangeBooster G Multifunction Print Server.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

The importance of names

Network filesharing problems often stem from improper workgroup and PC naming. Ensure each PC has a unique name to avoid mix-ups, don't use spaces in names and restrict yourself to 15 characters or less.

All PCs should use the same workgroup name. In XP Home the default is MSHome; in other versions of Windows, including Vista, it's Workgroup. To change either the workgroup or the computer name in XP, click Start, Control Panel, System and choose the Computer Name tab.

The Vista difference

If you're working in XP and have unresolved sharing issues, consider upgrading to Windows Vista. Its Networking and Sharing Center states which sharing features are enabled and makes configuring them easy. Vista's Link Layer Topology Discovery automatically detects network devices and shows their locations on a Network Map.

Vista's firewall is clever enough to permit sharing within a workgroup. If you're having a problem with XP's firewall, try a third-party utility. ZoneAlarm's Trusted Zone feature (zonelabs.com) allows workgroup computers to communicate.

To sidestep XP's file- and printer-sharing complexities altogether, try Network Magic. Network Magic puts all sharing and networking functions in one place. A special mode protects shared folders when your laptop is connected at a Wi-Fi hotspot, which can be a major security concern.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

Beef up security

The only way to guarantee the security of your network is to barricade it from the outside world – and that means no internet and no email. But you needn't adopt such extreme tactics to keep your data reasonably safe.

The road to a secure home network begins with a hardware firewall. Most routers have one, but those built into some inexpensive routers rely on NAT (network address translation) rather than using SPI (stateful packet inspection) technology.

SPI's superior approach ensures that your PC receives only data it has specifically requested. Be sure you change your router's default password when you set it up and periodically thereafter.

Establish a second line of defence by turning on automatic Windows Updates and installing antivirus, antispyware and personal firewall software.

Either buy a security suite (Symantec Norton 360 and McAfee Internet Security produce reputable packages, or use individual utilities.

Webroot SpySweeper , BitDefender Antivirus and ZoneAlarm are a good start.

XP's Windows Firewall filters incoming data only, so don't rely on it. A bi-directional firewall such as those included in ZoneAlarm or Norton 360 will monitor and protect both incoming and outgoing information. Vista's firewall is bi-directional, but you have to configure outgoing filtering yourself.

Vista features Windows Defender antispyware but no antivirus app.

Keep things simple by using the same utilities on all your PCs – look for economical 'family packs'. Install them while signed in as an administrator. If you've got kids, use the parental controls found in many packages (and in Windows Vista). Keep your password secret. Remember, your network is only as secure as its weakest link.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

Cover the airwaves

Firewalls and security suites are futile against packet sniffers that capture wireless traffic on a given frequency. Use the strongest encryption your Wi-Fi equipment supports. From strongest to weakest, the options are WPA2 (Wi-Fi Protected Access 2), WPA and WEP (Wired Equivalent Privacy).

Intruders armed with readily available software can break into WEP in minutes, rendering it worthless except as a method to prevent bandwidth-stealing neighbours. Invest in new adaptors if necessary to ensure that you can make the switch to WPA. To provide both old and new adaptors with maximum security, choose a router that offers a WPA+WPA2 mode.

Regardless of anything you may have heard to the contrary, neither using MAC (media access control) address filtering nor turning off SSID (service set identifier) broadcasting is an effective security measure. Both are easier to bypass than WEP and can create connection and administration hassles.

MAC-address filtering, for example, requires you to enter a device's MAC address into your router's firmware to authorise it to connect to your network. But anyone listening in can spoof your authorised MAC addresses on their own equipment. Similarly, sniffers can detect even non-broadcast SSIDs, so turning off broadcasting merely makes it harder for legitimate users to connect to your network.

Avoid hotspot hijacks

Open wireless hotspots are notorious sources of infection. For true security on public networks, use a VPN (virtual private network) to encrypt all internet traffic between your computer and an intermediate server. Companies often run VPN servers, or you can sign up for a service such as WiTopia personalVPN or JiWire Hotspot Helper.

For casual Wi-Fi connections, BT Openzone runs as a prepay subscription service or you can buy a voucher at a hotspot. Similar setups are provided by Boingo and The Cloud.

Most mobile phones are now web-enabled – getting online costs as little as £5 per month for 3 customers.

Next, in your Wi-Fi settings, turn off ad hoc (computer-to-computer) networking and prevent your laptop automatically connecting to networks that aren't in your preferred list. In XP, you can change both these settings by clicking the Wi-Fi icon in the system tray and selecting 'Change advanced settings'.

Under the Wireless Networks tab, click Advanced, followed by 'Access point (infrastructure) networks only'. Untick 'Automatically connect to non-preferred networks'.

In Vista, turn off the Vista Network Discovery feature when you're at a hotspot. Vista will switch it off automatically if you designate a connection as Public, but you can disable it manually in the View Network Status and Tasks control panel.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

Speed up transfers

  • Use wires whenever possible: A wired network (ideally one based on wired ethernet) is inherently more reliable and usually much faster than the open airwaves. There's generally no reason for you to locate a network storage drive at a distance from your router, so plug it into an ethernet port. The same goes for a network printer.
  • Get gigabit: Most recent PCs have built-in gigabit ethernet, which means they can transfer data at a whopping 1,000Mbps (megabits per second) – but only if your router possesses a gigabit switch. For network backups, the extra throughput can mean the difference between an all-night operation and one that completes itself in a short amount of time.
  • Buy matching Wi-Fi gear: To achieve the top speeds promised by the latest Wi-Fi standard, draft-802.11n, every wireless device on your network must have a draft-N adaptor (about £50 each). Update the firmware on any draft-802.11n devices regularly. Vendors are now bringing the first

The biggest obstacle to good Wi-Fi reception is no longer distance, since most Mimo (multiple input, multiple output) and draft-N routers are able to cover an entire house. Interference resulting from nearby networks in any urban area is, however, a concern. Fire up your laptop at home and you'll probably see a long list of networks.

Because the 2.4GHz band within which 802.11b, g and most n gear operates has only three non-overlapping channels, networks in the vicinity of yours are likely to degrade your throughput. The latest 802.11n draft in effect mandates a 50 percent reduction in performance when your network is in the presence of other active Wi-Fi networks.

To minimise interference, install and run a utility such as NetStumbler to determine the strength and channel of each available network. Set your router to the channel farthest from those of the strongest nearby networks. A router's automatic channel selection feature does this for you.

A dual-band draft-N router is a useful option. The Buffalo Nfiniti Dualband Router lets you run 802.11b/g devices on the busy 2.4GHz band while using 5GHz for high-bandwidth apps.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

Stop interfering

When it comes to smooth video playback and VoIP (voice over IP) calls, speed alone isn't enough. Physical limiters such as walls or interference from electrical items – microwaves are notorious – are a problem.

Powerline networks, which run over the mains electrical circuits in your home or office, are a good option where Wi-Fi and ethernet aren't up to the job. Several Powerline technologies offer connections almost as fast as ethernet. We found that for streaming HD (high-definition) video, Homeplug AV was the least susceptible to interference from electrical devices.

See also: Powerline: last refuge of the inept networker

Products such as Linksys's PowerLine AV Ethernet Kit move data over your home's electrical wiring, with adaptors plugging into a standard wall socket. Begin by connecting an adaptor to an available ethernet port on your router, then add other devices by running cables from their ethernet ports to other adaptors you've plugged in.

You won't have to worry about overloading your wireless network with HD video streams and performance will be far more reliable than on a wireless network, especially in a large home.

Draft-N on its way

If you prefer to stick with Wi-Fi for media streaming, you'll need hardware that offers draft-802.11n wireless support. As well as being fast, it incorporates a useful feature known as QoS (quality of service). This prioritises media streams, VoIP phone calls, online gameplay and other time-sensitive applications. Now that the 802.11n Wi-Fi specification has been agreed upon, version 2.0 of the draft standard has been issued – if you already have some draft-N kit, head to the maker's site and upgrade your firmware.

For online games fans, a specialised gaming router will give you a headstart against your opponents. This helps deliver maximum performance for internet and local multiplayer gameplay. It makes the most difference if several users access the network simultaneously.

Gaming routers have QoS prioritisation, are tuned to reduce latency and usually have faster processors, all of which increases the responsiveness of PCs on the network. For around £100 Linksys's Wireless-N Gigabit Gaming Router supports draft-802.11n Wi-Fi and gigabit ethernet.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.

A superior backup setup

If you're having trouble with backup, there are several possible causes. The network share may not be mounted, making it invisible to your backup program – adding it to My Network Places will avoid this. It's also possible that the PC to be backed up is off or in sleep mode, or the backup process may have been interrupted.

Make sure you buy the right type of network drive. Standard external USB drives are designed to attach directly to the USB storage port included on some routers or via an ethernet adaptor such as a NAS (network-attached storage) drive with built-in ethernet.

If you decide on a USB drive you can usually detach it from your router and plug it into a PC, perhaps at another location. True network drives, in contrast, have their own processor and OS (operating system), and can be attached only to your network. They generally have more features and will allow you to set up private user accounts (shares) as well as public areas that can be accessed by anyone.

For optimal security and performance, use a NAS drive with gigabit ethernet (you'll need a gigabit router if you don't have one) and Raid (redundant array of independent disks) 1 or 5 redundancy. Don't risk losing a 500GB music collection stored on a NAS drive without any backup – the best way to maintain a copy of your NAS drive is to mirror it using a Raid array.

Whichever type of drive you choose, make sure it's large enough to accommodate future growth. Backups often fail because the drive is full. We recommend setting aside twice the storage capacity of your current network. Double that again if you intend to mirror your network drive.

Incremental backups copy only files that have changed since the most recent backup, vastly reducing the load on your network and the length of time it takes to perform a backup. Cobian Backup 8.0 can perform full or incremental backups with or without compression and can encrypt data on shared network drives.

The need to ensure that your PC is up and running at backup time may seem obvious, but offline PCs are the most common cause of failed backups. Don't turn off your machine at night; let it hibernate. Use XP's Scheduled Tasks wizard (Programs, Accessories, System Tools) to ensure your backup software can wake up your PC.

Add a Mac

Many of us are not only multi-PC but multi-OS owners. Getting both Macs and PCs to recognise the same peripherals can be a chore, and filesharing is a concern.

In most cases Mac OS X provides everything you need to connect your Mac to a Windows network and share files and printers. You can plug a Mac into a wired network or access your wireless router, just as you would with a new PC, by selecting your SSID from a list of available Wi-Fi networks and then entering your wireless encryption key. Recently released Macs support WEP, WPA and WPA2.

To share files and printers, the Mac cleverly assumes the guise of a PC. It does so by implementing the SMB/CIFS Windows filesharing standard and using Windows workgroup naming. The default workgroup name for any Mac is Workgroup. You can change this name by running the Mac's Directory Access utility.

Turn on Windows Sharing in the Mac's Sharing Preference pane and enable each of the user accounts you'd like to share.

The Mac should appear as a member of your workgroup when you browse your network.

After selecting it and entering your username and password, you'll be able to navigate the Mac's hard drive and copy or upload files by dragging and dropping.

This works in both XP and Vista.

You can print from your Mac to shared Windows printers via SMB, although the setup process is not obvious. In the Mac's Printer Setup Utility, click Add. If your Windows printer doesn't show up in the resulting list of available printers, hit the More Printers button.

Now select Windows Printing and Network Neighbourhood from the drop-down menus. Your local workgroup will appear in the window. When you select it, you'll see a list of shared printers to choose from. Thereafter, the Windows printer will appear in the Mac's Print dialog box.

Quick links:

Wi-Fi: nail the basics

Wi-Fi: disappearing printers

Wi-Fi: the importance of names, and the difference Vista makes

Wi-Fi: how to beef up security

Wi-Fi: cover the airwaves and avoid hotspot hijacks

Wi-Fi: speed up transfers

Wi-Fi: preventing interference, and what to expect from draft-n networking

Wi-Fi: better backups and cross-platform networking

For more information on network security, our sister site Techworld has a comprehensive network security resource page.