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Small Wireless Network

Submitted by Peter on Tue, 2007-02-27 01:00

What is the total cost of implementing a wireless LAN with two computers using the wireless connection?

Patricia in the United States

A wireless network needs a network card in every computer. Modern notebook computers have wireless connections built in. A router connects the computers together and connects to the Internet. You need One true router to connect them all.

Here are the best solution and alternative for a small number of computers.

Speed

Wireless networks are painfully slow compared to a broadband connected gigabit LAN. Networks can be type b, g, a, or a proprietary improvement. D-Link, Netgear and other suppliers offer equipment that works with the old b class, in case you have an old b class notebook, the g and a standards for new notebooks, and a double speed g system that gives you 108 Mbps (megabits per second). The next generation of wireless is called class N.

The slowest speed, the old class b, is equivalent to old dialup speeds. Your time is worth too much to put up with the old speed. You can update old notebooks by switching off their internal wireless connection and plugging in a modern connection.

108 Mbps is roughly the same as the average LAN connection. LANs run at 10, 100, or 1000 Mbps, with 1000 Mbps commonly called Gigabit. Many businesses still use 100 Mbps instead of 1000 Mbps. Broadband connections can be 10 or 100 Mbps with a further limiting of speed based on the money you pay to the supplier. A cheap service might connect your computer to their modem at 100 Mbps but supply only 0.5 Mbps or 0.2 Mbps to the modem.

I have a premium broadband cable connection that starts close to 100 Mbps and stays about that speed until I reach a usage limit where the speed drops down. On a good day I can download the total contents of a DVD, that is 4700 Megabytes, in 20 minutes. When you sent data over the network, a byte of data is roughly equivalent to 10 bits of network speed. 4700 MByte is about 45000 Mbit. 45000 Mb over 20 minutes is 46 Mbps continuously over the entire 20 minutes during which I was downloading other files and browsing the Internet.

The next generation of wireless boasts a higher speed and a longer range plus multiple antennae to help the wireless signal travel around obstructions. The formal name the next generation is 801.11n and the common name is class N. The next generation is not yet an agreed standard but you can buy hardware for the almost final draft of the standard and the hardware is commonly named draftN.

ADSL

Most people use ADSL which varies in speed based on your distance from the telephone exchange with 8 Mbps being common up close to an exchange, incredibly slow speeds at 5 kilometres from the exchange and complete failure at 5.5 kilometres. ADSL2 replaces ADSL with 24 Mbps near the exchange, 1.5 Mbps out at 5 kilometres and complete failure at 6.3 kilometres. There is an ADSL2 with an extended reach that will give you slightly faster speed beyond 4 kilometres and stretch till 6.7 kilometres before failing.

Wireless connections are less reliable and more variable than ADSL. If you want to match the 24 Mbps of ADSL2 everywhere in your home or office, you will have to start with the 54 Mbps of the G class wireless because reception and speed quickly drop off at small distances away from the wireless transmitter in the router. When you walk the other side of a wall, the connection speed might drop from 54 Mbps to 32 Mbps. One more wall then you could be at 20 Mbps or 12 Mbps. Outside in the sunny garden the signal might be so weak that the system drops down near dialup speeds.

A better wireless system will not help you access the Internet faster when your computer is close to the transmitter but it will help when you are further away. When you are in the next room, where 54 Mbps drops to 32 Mbps, you might see a higher speed system drop from 108 to 64, which will still deliver ADSL2 at maximum speed.

Pre-N

Pre-N was the next step up in speed in 2006 and is a temporary step towards 802.11n, the new standard that may be approved in 2008. Belkin, Netgear, D-Link and others sell Pre-N equipment with most equipment varying by manufacturer, which means it only works if you buy everything from the same manufacturer. There is a draft standard for 802.11n and 12000 questions logged against the draft. 802.11n could be significantly different by the time anything is approved. Pre-N equipment is rapidly being replaced by draftN.

Range

The range of most wireless devices is pathetic. You can have a problem sitting in a large room if there is a television set between you and the network router. You can walk in to the next room, if the walls are wood, but will have problems when the wall is steel reinforced concrete or any form of metal sheet. When you walk outdoors, you are surrounded by water in the leaves of shrubs and trees, water absorbs microwave transmissions, including network signals, and the water absorption is a real problem.

If you want to see the water absorption problem in action, walk in to the woods with a mobile phone (cell phone) and an am or fm radio. The radio will work long after the mobile phone cuts out because am and fm radio are using frequencies that are not absorbed by water. Mobile phones, microwave ovens, and your wireless LAN all use water loving frequencies.

Get an extended range wireless network so you can walk around your house and garden without restriction. Look for MIMO equipment, which uses multiple antennas, Multiple Input Multiple Output antennas, then tries to pick the best combination for each connection. You will also get better reception inside your car when you are making last minute checks of addresses before driving off. The best Pre-N stuff offers double the range and double the speed at a given range. MIMO antennas improve the chances of your connection working at the highest speed. Draft N devices with MIMO can quadruple the range.

Security

Wireless LANs used WEP, Wireless Equivalent Protection, but WEP was not equivalent to a regular network. WPA, Wi-Fi Protected Access, replaces WEP. WPA-PSK, Wi-Fi Protected Access Pre-Shared Key, is a variation of WPA and there is a WPA2 for extra safety.

Each level of security requires more computing power in the transmitter/router device, which means buying something above the cheapest available device. If you are looking at one router on sale for $99 and another newer model for $150, the difference could be the extra power needed for decent security.

Hardware

Network Router

Networks use hubs and routers to connect multiple computers and broadband. You could use just two wireless adapters to connect two computers and connect broadband through one of the computers but you would be limited to those two computers and the computer with the broadband connection would have to be on all the time. A router lets you connect more computers, including your friends when they visit, and gives you better control over the network. Routers have more intelligence than hubs and you need the intelligence for the security features which means you need a router.

You can save a couple of dollars by buying routers that include a DSL modem but you usually get a second rate wireless connection. Pay the extra few dollars to get the best wireless router and a separate DSL modem. When lightening or static electricity destroys your DSL modem, you will be glad your DSL modem was not built in to your router. I replaced three broadband modems in four years while the attached Netgear router survived several years of harsh treatment, including people standing on it, then survived the four years attached to the broadband modems.

Firewall

You need a firewall or intelligent router somewhere between your computer and your Internet connection. One option is to install a firewall on your computer and connect other computers through your computers. You then have to leave your noisy hot computer switched on all day and night every day of the year. Life is much easier if you buy a small quiet firewall appliance. Firewalls are built into the better routers.

Notebooks

Your notebook probably has 802.11g built in, the 54 Mbps current standard. You may need a network card for higher speeds or longer distances. The network card will have to match the transmitter until after 2008, when there will finally be a standard for higher speed wireless networks. Today you can buy premium equipment based on draft versions of the standard and the best models have Wifi approval, based on the final draft. You can also get first class equipment providing QoS, Quality of Service, which pushes voice traffic ahead of other traffic, extremely important when you talk over VoIP on a busy network.

USB

Wireless adapters are available as USB devices and, if you work in an office, you will find people borrowing your device then forgetting to return it. PCI adaptors have the advantage of staying in the computer on occasions when people steal plug in devices. People are far less likely to borrow devices that require a screwdriver and 10 minutes work.

Two Computers Direct Connection

You can save a couple of dollars by connecting two computers together without a router. You are then limited to only two computers. I sometimes do this when installing a new computer and copying from an old computer but would never run a network that way because there is often a need to connect a third computer, a visitor's computer or an experimental machine. Start with a router to save the work of changing the network later.

First Class

When you want to connect more than two computers, you need a router. D-Link offer a superb router that is Wifi approved, has QoS, and Gigabit speed over the wired network, the DIR-655 Xtreme N Gigabit Router. You get up to 14 times the speed of g class and several times the range when used with matching D-Link Xtreme N devices. The Wifi certification means the router is likely to work at top speed with Wifi approved draft N devices from other manufacturers.

D-Link offer a great network card for notebooks fitted with the new ExpressCard slot, the DWA-643 Xtreme N Notebook ExpressCard. You get all the speed and range of the Xtreme N router in the new smaller faster ExpressCard format.

Older notebooks will require a larger Cardbus style adapter and D-Link offer the DWA-652 Xtreme N Notebook Adapter. The DWA-652 has exactly the same wireless connection as the DWA-643 in the larger Cardbus format and Cardbus slots have existed in notebook computers for many years, which means this card should work in most notebooks.

Desktop computers need PCI adapters or the newer faster PCI Express adapters. D-Link have the DWA-556 Xtreme N PCI Express Desktop Adapter.

Older desktop computers will like the D-Link DWA-552 Xtreme N Desktop Adapter.

Economy Class

D-Link offer economy equipment, the AirPlusXtremeG range, that is twice as fast as class g and has several times the range of class G. If you live in a small house or apartment, where you not need the extreme range of the draft N devices, you can save a couple of dollars with the economy range. When you are connected to older broadband, anything before ADSL2, you cannot connect to the Internet at the speed of draft N devices. You could start a wireless network now with D-Link's lower priced AirPlusXtremeG devices and leave the purchase of the higher speed stuff until the 802.11n standard is ratified in 2008.

D-Link offer an economy router, the DI-624 High-Speed 2.4GHz (802.11g) Wireless 108Mbps1 Router, for extra speed and range over class g. You can plug in four wired connections for existing desktop computers.

I use a DGL-4300 which is a DI-624 with Gigabit wired connections instead of 100 Mbps wired connections but the DGL-4300 is no longer sold by D-Link. If your desktop computer has existing wired Gigabit then you need the new DIR-655.

D-Link offer an excellent network card for notebooks, the DWL-G650 AirPlusXtremeG Wireless Cardbus Adapter. You get double the speed and range when used with a matching D-Link AirPlusXtremeG router. If you have a notebook with a built in network connection but it is the older class b, treat yourself to a faster connection.

You cannot use a PC card with desktop computers which means the DWL-G520 AirPlusXtremeG Wireless PCI Adapter is your next choice.

If you want a portable alternative for both desktop computers and notebooks then buy a USB adaptor, the DWL-G132 AirPlusXtremeG Compact Wireless USB 2.0 Adapter.

Cost

The following shopping list is based on my office when upgrading an older desktop computer, with PCI slots, and a current notebook that has Cardbus slots. You might need the newer PCIExpress or ExpressCard devices. The list does not include the broadband modem.

America

Item Premium Economy
Router:    
Notebook adapter    
Desktop adapter    
  ========   ========
Total    
    ========    ========

Australia

Item Premium Economy
Router: $379.00 $136.00
Notebook adapter   Not yet available $79.00
Desktop adapter Not yet available $79.00
  ========    ========
Total ? $294.00
  ========    ========

Conclusion

Use the D-Link draft N equipment, the XtremeN range, including the router with Gigabit wired connections, for new computers to get the raw speed and longer range. Use the economy option for any set of older computers that will not be upgraded until after 2008, when draft N will be replaced by a genuine standard.