Networking: Wired or Wireless?
About Wireless LANs
Popular WLAN technologies all follow one of the three main Wi-Fi communication standards. The benefits of wireless networking depend on the standard employed:
- 802.11b was the first standard to be widely used in WLANs.
- The 802.11a standard is faster but more expensive than 802.11b.
- The newest standard, 802.11g, attempts to combine the best of both 802.11a and 802.11b.
No other networking technology used to set up a small home or SOHO network provides the convenience or mobility of a Wi-Fi network. That's because other methods, including standard wired Ethernet networks and phone line- and power line-based networks, all require a connection via wire or cable. Wi-Fi uses radio waves that travel through walls and floors and connect you anywhere, indoors or out.
Installation
Wi-Fi networks can be configured in two different ways:
- "Ad hoc" mode allows wireless devices to communicate in peer-to-peer mode with each other.
- "Infrastructure" mode allows wireless devices to communicate with a central node that in turn can communicate with wired nodes on that LAN.
Most LANs require infrastructure mode to access the Internet, a local printer, or other wired services, whereas ad hoc mode supports only basic file sharing between wireless devices.
Both Wi-Fi modes require wireless network adapters, sometimes called WLAN cards. Infrastructure mode WLANs additionally require a central device called the access point. The access point must be installed where wireless radio signals can reach it with minimal interference. Although Wi-Fi signals typically reach 100 feet (30 m) or more, obstructions like walls can greatly reduce their range.
Cost
Wireless gear costs somewhat more than the equivalent wired Ethernet products. At full retail prices, wireless adapters and access points may cost three or four times as much as Ethernet cable adapters and hubs/switches, respectively. 802.11b products have dropped in price considerably with the release of 802.11g, and obviously, bargain sales can be found if shoppers are persistent. This must be offset against cost of paying for cable and the engineers to install it.
Reliability
Wireless LANs suffer a few more reliability problems than wired LANs - though tripping over the cables and pulling them out of sockets/computers/hubs isn't one of them!). 802.11b and 802.11g wireless signals are subject to interference from other home applicances including microwave ovens, cordless telephones, and garage door openers. With careful installation, the likelihood of interference can be minimized.
Wireless networking products, particularly those that implement 802.11g, are comparatively new. As with any new technology, expect it will take time for these products to mature.
Performance
Wireless LANs using 802.11b support a maximum theoretical bandwidth of 11 Mbps, roughly the same as that of old, traditional Ethernet. 802.11a and 802.11g WLANs support 54 Mbps, that is approximately one-half the bandwidth of Fast Ethernet. Furthermore, Wi-Fi performance is distance sensitive, meaning that maximum performance will degrade on computers farther away from the access point or other communication endpoint. As more wireless devices utilize the WLAN more heavily, performance degrades even further.
The greater mobility of wireless LANs helps offset the performance disadvantage. Mobile computers do not need to be tied to an Ethernet cable and can roam freely within the WLAN range. However, many home computers are larger desktop models, and even mobile computers must sometimes be tied to an electrical cord and outlet for power. This undermines the mobility advantage of WLANs in many homes.
Security
In theory, wireless LANs are less secure than wired LANs, because wireless communication signals travel through the air and can easily be intercepted.
To prove their point, some engineers have promoted the practice of wardriving, that involves traveling through a residential area with Wi-Fi equipment scanning the airwaves for unprotected WLANs.
On balance, though, the weaknesses of wireless security are more theoretical than practical. WLANs protect their data through the Wired Equivalent Privacy (WEP) encryption standard, that makes wireless communications reasonably as safe as wired ones.
No computer network is completely secure and companies and homeowners should ensure they are aware of and comfortable with the risks.
