Networking standards: 802.11g | 802.11b | 802.11a | Dual band | Bluetooth | HomePlug | Ethernet Network standards at a glance
802.11g
The 802.11g standard, long touted as the high-performance successor to
802.11b, was ratified in June 2003, but networking manufacturers
flooded the market with 802.11g gear months before the final
specification was approved as a standard. Most of the gear that was
sold prior to ratification will need a firmware upgrade to bring it up
to the final spec. 802.11g has two features that many believe will make
it the new dominant Wi-Fi standard: great throughput at around 22Mbps
and backward compatibility with 802.11b. That's right; 802.11g operates
at the same frequency as 802.11b (2.4GHz) and is backward compatible
with the granddaddy of Wi-Fi specs. This makes 802.11g the obvious
choice not only for anyone building a new network, but also for those
interested in adding onto or gradually upgrading a preexisting 802.11b
network. The only downside to 802.11g is the fact that it uses a
crowded slice of the spectrum, with room for only three nonoverlapping
channels. This will make 802.11a a better choice for some environments,
especially those populated with devices that share the 2.4GHz spectrum,
such as cordless phones, baby monitors, microwave ovens, and Bluetooth
radios.
802.11g facts
• Better range than that of 802.11a products
• Much faster than 802.11b products
• Low cost
• Subject to interference from other 2.4GHz devices
• Only three nonoverlapping channels
802.11b
The price of 802.11b gear has dropped dramatically over the last year.
This gear operates at 2.4GHz and offers a real-world throughput of
around 5Mbps at close range. In a typical indoor environment, without a
lot of metal, 802.11b equipment can generally maintain a solid
connection up to about 150 feet. It is also fully compatible with the
faster 802.11g standard. The weaknesses of 802.11b are its
comparatively low throughput and the potential for interference with
other gadgets that share the 2.4GHz band, such as cordless phones,
security radios, and microwaves.
802.11b facts
• Better range than 802.11a products
• More than adequate throughput for broadband sharing at around 5Mbps
• Slower than 802.11a and 802.11g
• Broad compatibility
• Low cost
• Subject to interference from other 2.4GHz devices
• Only three nonoverlapping channels
802.11a
The 802.11a standard has a couple of advantages over the more prevalent
802.11g. It runs at a less populated frequency (5.15GHz to 5.35GHz),
making it less prone to interference, and its practical throughput is
about four times greater than that of 802.11b, typically clocking in at
around 22Mbps. This gives it a lot more elbowroom than 802.11b for
streaming digital audio and video or transferring large files over the
network, with bandwidth left over for Internet sharing. Some
manufacturers offer proprietary turbo modes that can push throughput
even higher. 802.11a's downside is its shorter range. Because 802.11g
and 802.11a operate at different frequencies, they can't talk directly
to one another, which is why if you have an 802.11a adapter, you cannot
connect to most hot spots. Another weakness is the increased power
drain of the 5GHz radio, as compared to its 2.4GHz counterparts.
802.11a facts
• Great throughput at around 22Mbps or higher
• Operates at 5GHz
• Low risk of interference from other devices
• Eight nonoverlapping channels
• Higher cost than that of 802.11b and 802.11g
Dual band
Wouldn't it be nice if you could get all of the 802.11 standards into a
single device? The latest wave of dual-band networking equipment gives
you just that. 802.11a/b/g gear operates at both 2.4GHz and 5GHz and
gives you the advantages of all three standards. You get the speed and
the resistance to interference of 802.11a, the broad compatibility and
the increased range of 802.11b, and the increased throughput of
802.11g--but you pay for it. Dual-band gear can cost more than twice as
much as its single-band counterparts, but for some, the added
flexibility will be worth the heftier price tag.
Dual-band facts
• Compatibility with all 802.11 standards
• Combines the fast throughput of both 802.11g and 802.11a
• All-in-one solution
• A combined total of 11 nonoverlapping channel