Getting Internet Service Requires More Than Excellent Signal Strength

As computers in general, and WiFi in particular, become more like home appliances and less tools or toys owned by the geeky or the wealthy, not everybody who needs Internet access will be able to get it at any given time. Some people aren't aware of the details involved, especially when using the convenient WiFi connectivity. Reports like

My Internet connection is Excellent, but when I start Internet Explorer, I see

The page cannot be displayed.

What is going on here?

are becoming more and more common in many forums.

Between turning on on your WiFi equipped computer, and seeing the home page of your choice pop up in the browser window, there are a few details which you need to consider.

• Is this your WiFi access point? Setup your WiFi access point so you connect only to it.
• Are there any signal interference sources inside your home? Make sure that noise doesn't prevent your connection.
• Is your WiFi security setup properly? Make sure that you can connect, but your neighbours can't hijack your connection.
• Is your selected WiFi channel available? Make sure that there is bandwidth available.
• Have you run a WiFi environment survey? Make sure that there is a channel available.
• Have you tried using Ethernet? Make sure that the problem is with WiFi, not your Internet service in general.

All of these are issues which involve WiFi connectivity, and all different ways. The bottom line, though, is that WiFi will never replace Ethernet. And there are other issues which affect Internet connectivity in general, but might still affect this computer, alone.

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Analyse Your WiFi Environment Objectively #2

When you have a WiFi LAN, and want to find out why it doesn't perform as well as you'd expect to, the first thing most folks will instruct you is

Do a WiFi site survey. Find out what your neighbours are doing.

When a site survey must be done, the best known procedure is to run NetStumbler.

But NetStumbler, for all its highlights of being easy to use, and well known, has shortcomings.

• It doesn't support 802.11n client equipment.
• It doesn't reliably detect 802.11n networks.
• It doesn't run under Windows Vista.

Fortunately, there are new WiFi spectrum analysers, available now, that may provide help where NetStumbler fails. Two such products are InSSIDer (from MetaGeek), and the Xirrus Wi-Fi Monitor Gadget for Windows Vista.

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No WiFi Connectivity? Check The Power Settings

So you just got yourself a new laptop computer, and of course a WiFi router so you can use the new computer while lying in bed (no we won't discuss why you want that). And you followed all of the instructions, and you run the WiFi client setup where it lists networks for you to connect to, and you see

No wireless networks are within range.

Dohh! Guess you won't be surfing the web from the bed after all.

But before you give up, and take it all back to the store, check everything again. To start, check power. There are up to 4 power settings, and yes, I will describe the obvious ones too.

• The laptop has a power switch.
• The router should (but probably doesn't) have a switch. But check the power cord. Of course, since you just ran the router setup (connected by Ethernet cable), the router must be on. OK, move on.
• If the laptop has built-in WiFi, it's got a power switch for the radio. The radio is the part of the WiFi device that uses the most power, so every laptop lets you turn the radio off. Most laptops ship with the radio turned off, so you won't use it without knowing that it's on. Read The Manual.
• Check the router setup, and make sure that the radio there is on. Most WiFi routers ship with the radio turned off, so you don't set one up, with the radio on, without knowing that it's on. This keeps you from inadvertently providing free Internet service to your neighbours. Again, Read The Manual.

Always check the power, after you set everything up. Then check all of the physical issues again.

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Automatic Metrics and The Ability To Roam Wirelessly

If you have a portable computer, and you've setup a WiFi LAN in your house or office, you'll enjoy the freedom of moving around the house, at will, while still connected to the LAN. Even so, sometimes there will be times when the WiFi connection isn't enough. You'll never get rid of Ethernet, completely.

Most portable computers come with an Ethernet adapter, and a WiFi adapter, installed and activated. The Automatic Metric feature in Windows XP let you leave both connections activated, and will use the fastest connection, that is working, at any time.

You can use automatic metrics (by default), or you can manually change the settings to prefer either connection, using the TCP/IP Properties - Advanced wizard.

NOTE: Using the Automatic Metric feature on a laptop having a role as a server on your LAN may cause problems with the browser infrastructure. Don't carry a server around without understanding the complications.

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Your Neighbour's WiFi

One of the limitations of WiFi is that it's not scalable, and it has a finite capacity. You cannot get more than (currently) 108M bandwidth. You simply won't be able to stream the latest movie in 3D multi-colour to every media computer in your house without seeing some performance limitations. And that is your own performance limitation. If your neighbour has a WiFi LAN, you will also have to share the bandwidth with him (her). WiFi simply does not have unlimited bandwidth, new technology or not.

In any domestic situation with neighbours, for a problem like a loud stereo, the tendency is to turn your own stereo up. Crank that sucker. This is, however, not a good, long term solution.

• You possibly have up to 8 immediate neighbours, and more beyond them. Some of those neighbours, also currently suffering from your neighbour stereo, now have to suffer from yours too.
• Your neighbour will probably turn his volume up yet again, to overcome the new "noise" from your system.

Like every analogy, this one suffers from a major problem. With loud stereos, it's easy to find where the noise is. Just follow your ears. Then call the police, and have them deal with the problem.

If your neighbour has a "loud" WiFi LAN (ie SuperG or MIMO), you won't be able to follow your ears. Nor will, I suspect, the police be interested in becoming involved. You're going to have to find your neighbour, and you're going to have to convince him to turn his stereo (WiFi) down. Or suffer in silence.

You can start with NetStumbler, and triangulate the problem. Then, you'll have to use diplomacy, not technology. You'll not solve the problem by getting a high power AP.

I, and others like me, have seen this situation coming for some time. Here is one possible real life example, and here is a second possible real life example. And even if neither discussion is diagnosed with this cause, this scenario is coming. Channel saturation, and unexplainable intermittent bandwidth variation, will become the norm, not the exception.

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Choose Your WiFi Client Manager Carefully

When I got my laptop, it came with built-in WiFi, and with 3 programs ("Client Managers") to manage the WiFi connection.

• HP - The laptop vendor.
• Intel - The WiFi card vendor.
• Microsoft - The operating system vendor.

The problem is, only one program can manage a WiFi card at any time. Multiple managers = confusion = random disconnects. Each Client Manager program will be different.

• Information displayed.
• Organisation of wizards to make settings changes.
• Security options.

The Microsoft product, Wireless Zero Config, has one major advantage. WZC runs as a service. If you depend upon your computer having connectivity without you being logged in, or even immediately after you login, you may find this a useful feature.

Just make sure that only one client manager is run, at any time.

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Analyse Your WiFi Environment Objectively

When you setup a network of computers, in your home or small office, a mass of Ethernet cables running everywhere can be a problem. WiFi, or Wireless networking, can provide relief from the mass of cables. But WiFi is not an effortless replacement for Ethernet. Installing a WiFi network takes careful preparation.

There are many reasons why you won't get the expected bandwidth from any WiFi network. Some of them you can correct, others you can't. And sometimes, even without you making any changes, you'll have problems. All the planning you do is useless when your neighbours install a WiFi LAN next door.

With all of that in mind, you need to evaluate your WiFi environment objectively, both before setting up a WiFi LAN, and after. When "it stops working", find out why. When your Ethernet network stops working, you can start with a simple IP scan of the subnet. With a WiFi network, you have to go a level deeper than Internet Protocol (sometimes, IP may not even be relevant).

There are many tools to objectively analyse your WiFi network; some are free, others cost good money. Here are but two.

Netstumbler makes a free, lightweight WiFi spectrum analyser from your computer and WiFi adapter of your choice. Netstumbler continuously scans the WiFi spectrum covered by your WiFi adapter, identifying each WiFi network device (whether access point / router, or client), and recording a dozen or so metrics about each network device found.

NetStumbler has two displays, both very useful. The display that you see immediately is the AP inventory, which enumerates each AP observed, and includes over a dozen very useful details about each. But you can discover more.

If you identify an interesting AP from the main list, you can find the MAC address for that AP. From a tree entry in the left column, you select a specific MAC address, and you can observe a running signal to noise graph for that network device.

Netstumbler, though free, and easy to use, has disadvantages.

• It does not work with every known WiFi adapter.
• It does not analyse non WiFi signals. If you have a cordless phone, microwave oven, or nearby ham radio operator, NetStumbler will show those merely as "noise", as part of the signal to noise ratio for any WiFi network device.
• NetStumbler binds to the WiFi adapter just like any other WiFi client. If you run NetStumbler while you're attached normally to your network, using WiFi, you'll experience the same instabilities as when when you run multiple WiFi client managers.
• It's not compatible with Windows Vista.

The Wi-Spy Spectrum Analyzer overcomes some of the disadvantages of Netstumbler. The Wi-Spy is a USB dongle / WiFi receiver, that will receive and analyse signals in the WiFi spectrum.

• It does not require an add-on WiFi adapter, and has no compatibility problems like NetStumbler.
• It provides the same sort of analyses about all detectable WiFi network devices, as NetStumbler. Also, it analyses the noise (signals from non-WiFi devices) in the spectrum, and attempts to identify the device producing the noise, from a database of known interference sources.
• It works with Linux, Mac, and Windows (Windows 2000 or XP, and yes, Vista).
• It is not inexpensive, but it is worth the price.

Note that NetStumbler has its shortcomings, in lack of support for new technology. Fortunately, alternative products are available.

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Stabilise Your WiFi - Use Only One WiFi Manager

When I got my laptop, I was not at all impressed with the WiFi performance. Two or three times daily, I would have to reboot it, or the WiFi router, to get the laptop online. Compared to Ethernet, and especially compared to the other computers in my LAN, this was unacceptable.

Even after researching all of the known WiFi instability issues, I got nowhere.

A month after first getting the laptop, I reformatted and reloaded the operating system. As a side effect of doing that, I inventoried the WiFi manager programs, and I had 3.

• HP - The laptop vendor.
  
• Intel - The WiFi card vendor.
  
• Microsoft - The operating system vendor.
  

As part of the effort of reloading the operating system, I realised that having three WiFi manager programs loading was not a good thing. So I carefully compared all 3 programs, and in my case, decided that the Intel WiFi manager program was the best for me.

Using Autoruns and Process Explorer, repetitively, I located and removed all startup entries for both the HP and Microsoft WiFi managers.

Since I reloaded the operating system, my laptop has been rock solid reliable. It, as my other computers, generally stays online 24 x 7 x 52.

When you consider doing this, you should plan on both proper preparation, and some detective work.

• WZC, the Microsoft supplied WiFi manager, is a service, and it starts when the computer is started up. WZC, as a service, runs as a system level process.
• Most vendor supplied WiFi managers start after the user logs in to the computer, and run as user level processes. User level processes don't have the ability to start, stop, enable, or disable WZC.
• You should plan on installing the WiFi device(s), and disabling / removing any extraneous processes (whether vendor or WZC), while logged on as an administrator.
• Many vendor supplied WiFi managers run as multiple processes, and you (as the administrator) may have to work to find all processes (as with Autoruns, as referenced above).

WiFi Will Never Be As Fast As Ethernet

With "Fast" Ethernet, you expect (and generally get) 100Mbps performance from the network. With Gigabit Ethernet, you expect (and possibly get) 1000Mbps. With 802.11g WiFi, you expect 54Mbps, but you seldom get that. Why is WiFi less reliable?

Ethernet (IEEE 802.3), and WiFi (IEEE 802.11) are Layer 2 specifications of the OSI Network Model. Physical Ethernet also occupies Layer 1 of the model.

If you observe the limitations imposed by IEEE specifications, you get predictable results - those limitations should exceed your operating requirements. For instance, 100M Ethernet is provided for cable runs of up to 100 Metres (300 feet) between the computer, and the other network device (generally a hub / router / switch, or another computer).

With Ethernet, you control the environment completely. That is, you own the physical network, and you control what you own. With WiFi, you use the radio frequency spectrum included in IEEE 802.11, but share that spectrum with other electronic devices. Some devices may be non compliant with 802.11 (baby monitors, portable phones, and microwave ovens may transmit on that frequency band), and may be treated as analogue interference. Other devices may be 802.11 compliant, but owned by your neighbours, may also operate in the same frequency spectrum, and may be treated as digital interference.

The bottom line - with WiFi, there are things you can't control easily, and others that you can't control at all.

• Ethernet is a full duplex, dedicated medium. WiFi is half duplex, and shared - it has one media, the WiFi channel, which has to be shared for both sending and receiving the packets. And it's shared with your neighbours.
  
  
• Ethernet is a mature technology - it's been around for much longer than WiFi. WiFi components have frequently upgraded firmware. Any time you ask the vendor for help, their first question will be "What version firmware are you running?". This is not a delaying tactic, or needless protocol - it's an attempt to ensure that your drivers are up to date, so they can help you effectively.
  
  Any time you get new hardware, you should always consider the possibility that the firmware was upgraded after your unit was packaged. Always get up to date firmware - and get it from the vendor.
  
  
• Ethernet is a scalable medium. With Ethernet, each computer has its own cable connecting it to the network. With "n" number of computers in an Ethernet network, you can theoretically have "n/2" simultaneous conversations between computers. As you add computers, and cables (and higher rate cables), the total amount of bits being passed in any network, simultaneously, increases constantly. With WiFi, there is a ceiling. At any location in a WiFi neighbourhood, you can have a maximum number of bits being passed, "simultaneously", shared among all WiFi devices near that location. WiFi is not scalable.
  
  
• Ethernet is a much more stable medium. With switched Ethernet, you have two hosts, for instance a router / switch, and a client computer. The two hosts are connected by a physical cable. The firmware and hardware on each host has to manage the conversation only with the other host.
  
  With WiFi, each host is managing / blocking conversations with dozens of other hosts (multiple channels, locations, and networks) constantly, and no two hosts are seeing the same complement of other hosts at any time or in any place. Managing relationships in the constantly changing WiFi population takes resources - and can make the WiFi device slower than it should be.
  
  Besides the constantly changing and differing population issue, there's the security needs. WEP, WPA, WPA2, AES, CCMP, TKIP... The list of security protocols and standards is endless, and changes frequently. Managing security in any WiFi conversation takes resources - and can make the WiFi device slower than it should be.
  
  
• Can you actually see a computer from the Access Point? With WiFi, if you don't have a clear line of sight visibility between the network devices, you'll not get a full strength signal. Distance is another factor. Signal strength falls off as distance increases. Put the computer in one room, and the AP in another (a normal use for WiFi), and see what signal strength you get. Walls and floors are a major signal problem. Signal loss will be higher if the signal has to travel diagonally thru the wall or floor, rather than at a right angle.
  
  
• Look at the antennas on the AP and the computer, and see how much they are parallel - you will get maximum signal strength only when the 2 are perfectly parallel. Draw an imaginary line, extending at a right angle, from one antenna towards the other. Does it intersect the other? Try and make a line between the two intersect at a right angle. Signal loss will be higher if one network device is located directly above the other, and on another floor, if both antennas are pointed vertically.
  
  To make this simplest to understand, look at some examples.
  
  
  
  • If the AP and a computer are in the same room, locate both devices so both antennas are the same height off the floor. Point both antennas vertically.
    
  • If the AP and a computer are on different floors, locate both devices so the antennas are immediately above and below each other. Point both antennas horizontally.
    
  • If the AP and a computer are in different rooms, position both so a line from one to the other goes at a right angle thru the wall. Locate both devices so both antennas are the same height off the floor. Point both antennas vertically.
    
  • When you can't be so precise in physical placement, point both antennas parallel to each other, per the above strategies.
    
  
  
• An Ethernet cable is a media that YOU own, and physically control. With WiFi, you have to share the channel with all of your neighbours. And, with CSMA/CA, the sum of your usable bandwidth plus your neighbours usable bandwidth will never add up to 54M (for 802.11g) or 108M (or whatever is promised, for 802.11n). Relying upon Collision Avoidance will always require wait time, where neither of you is transmitting. And the more neighbours that you have, the more time that your equipment will be waiting to use the channel.
  
  
  
  • If your equipment is compatible, you may benefit from using NetStumbler, or a similar product. Find out how many of your neighbours are also using WiFi, and how close each is.
    
  • Try using a channel that isn't being used by a neighbour close to you. With 802.11G 54M, only channels 1, 6, and 11 don't overlap in frequency. If you have 2 neighbours - one on channel 1, and the other on channel 6, your best choice (avoiding digital interference) is channel 11. Analogue interference, or noise, may make this conclusion less certain.
    
  • Remember that wireless networks may come and go, so watch over a period of hours, if not days. NetStumbler is great for this - leave it running, and it will make a running list, showing each observed access point, and graphing its signal strength by time.
    
  
  
• Your wireless neighbours are interference sources outside your home. You probably also have interference sources inside your home.
  
  
  
  • Baby monitors.
    
  • Computers.
    
  • Cordless phones.
    
  • Microwave ovens.
    
  • Wireless stereo speakers.
    
  
  If you install a WiFi device on your desktop computer, try and get one with an antenna that you can move above, and away from, the computer. Signal loss will be higher with a PCI WiFi card, with the antenna stuck at the back of the computer. This is particularly the case if your computer is a tower, sitting on the floor. The higher the antenna from the floor, the better the signal level.
  
  
• You will only get maximum performance from similar equipment, and with no WiFi neighbours. You will have to share the channels with your neighbours. In any WiFi neighbourhood, no two WiFi devices will be within range of the same complement of other WiFi devices. The hidden node problem, where it is recognised that no two networks have to share the spectrum with the identical complement of other networks, is a well known WiFi issue.
  
  
• Maybe the router configuration has a setting that's causing your problem. Start by checking your Transmission Rate setting.
  
  
  
  • If it's on Auto, try setting it to a realistic rate. Start by setting it at the rate you think you're getting, and see if your bandwidth improves even slightly. If there is any problem with your signal, auto may make the router spend more time recovering from problems, and less time actually sending and receiving.
    
  • If it's on a low rate, try setting it at a higher rate. See if your bandwidth improves.
    
  • When tuning your Transmission Rate, using NetStumbler to analyse performance would be a very good idea.
    
  
  
• For more thoughts on this subject, see BBR Forums How Can I Boost My Range? (#10944).
  
  
• And consider that, even though WiFi doesn't use wires as heavily, general physical networking principles may still apply.
  

And however you set up your WiFi in the end, please secure your LAN. The performance hit you get, when your neighbours WiFi LAN comes on, pales in comparison to what happens if your computer is hacked, and joins a botnet.

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