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Wireless Routers - Standards
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Routers allow computer and Game console to share internet






How to Buy a Wireless Router

Routers - wireless how to setup network

Think of Wi-Fi as a radio signal, only in a higher frequency than AM or FM radio.
The AM radio band in the United States covers frequencies from 540 kHz to 1700 kHz
The FM radio band covers frequencies from 88 MHz to 108 MHz
Wi-Fi is higher frequencies, in the GHz bands

Wi-Fi Routers - Standards

Routers Wireless b (1999), g (2003), n (2009), ac, ax

802.11ac is Wi-Fi 5 (2013)
802.11ax is Wi-Fi 6 (2019)
Wi-Fi 6E (2021)

Wi-Fi routers operate on the 2.4, 5, and 6 GHz bands.

Wireless Routers -

What is the Difference Between Wireless G and Wireless N


Wireless Networking - Wireless Devices

What is the difference between 802.11g and 802.11n?
Networking, Communications, Wireless
802.11 Wireless

Wireless-N Gigabit Router
802.11 is the wireless communication standard created by the IEEE (Institute of Electrical and Electronic Engineers) society. 802 is the number classifying all standards relating to Networking, be it WAN, LAN, or WLAN technologies. 802.11 is specific to standards dealing with wireless networking. That standard is further broken down into letters, such as 802.11a, 802.11b, 802.11g, 802.11n

Common Wireless Standards

802.11a is a WLAN communication standard. 802.11a is one of the wireless Ethernet standards in the 802.11 series. 802.11a wireless networks support a maximum theoretical bandwidth of 54 Mbps. 802.11a's principal advantage over 802.11b, that supports 11 Mbps, is improved performance. However, 802.11a access points (APs) and adapters also cost significantly more than their 802.11b counterparts. 802.11a transmits radio signals in the frequency range above 5 GHz. This range is "regulated," meaning that 802.11a gear utilizes frequencies not used by other commercial wireless products like cordless phones.

In contrast, 802.11b utilizes frequencies in the unregulated 2.4 GHz range and encounters much more radio interference from other devices. Examples: Though it helps improve network performance and reduce interference, the range of an 802.11a signal is limited by use of the high 5 GHz frequency. An 802.11a AP transmitter may cover less than one-fourth the area of a comparable 802.11b AP. Brick walls and other obstructions affect 802.11a wireless networks to a greater degree than they do comparable 802.11b networks.

In the beginning 802.11a and 802.11b were used, but today the vast majority of wireless devices run on either the older 802.11g protocol or the newer 802.11n protocol. There are many differences between these two standards, meaning they are not "backwards compatible" like 802.11g was to 802.11b. However, if you are using a mix of N and G standardized devices, most wireless routers that support N will also support G - but count on speeds being limited to the "oldest" standard currently running.

Features of 802.11g

802.11g was the fastest wireless networking protocol until wireless N. Like 802.11a, 802.11g supports a maximum speed of 56Mbps (mega-bits per second). However, unlike 802.11a it functions on the 2.4GHz band. This means that G was not compatible with A. However, the slower (11Mbps) 802.11b was compatible, as it also worked on the 2.4GHz band.

The problem with G is not so much that it is too slow (56Mbps for wireless is pretty respectable) but that it shares a wireless band with many common devices that cause considerable interference. For example, most cell phones, cordless phones, Bluetooth, and microwaves share the 2.4GHz band. In fact, if it were not for this problem we probably would not have an 802.11n in the first place, since 802.11g can be pushed up to 108Mbps on some devices ("super-G").

Standard: 802.11g
Band: 2.4GHz
Speed: 54Mbps, or 108 Mbps

Features of 802.11n

Wireless N uses a technology known in the industry as MIMO. This stands for multiple input, multiple output. In effect, instead of a device having a single antenna, it has multiple antennae that are arranged so as to have maximum transmitting power, and maximum reception. Wireless N claims "real world" speeds of 130-160Mbps, with a listed maximum of 300Mbps. This is reliant on the router transmitting in full 802.11n mode, which is impossible when an 802.11g device is also connected to the network. As far as the wireless band goes, 802.11n devices can operate on 2.4 or 5GHz bands. However, to use 5GHz all connected devices must be 802.11n compliant. Note, too, the 5GHz band will significantly decrease the maximum range. The tradeoff is that there will be much less interference, and 5GHz is drastically more effective at penetrating concrete and brick walls.

Differences between 802.11a, 802.11b, 802.11g and 802.11n

Wi-Fi

* 802.11a:
o Operates in the 5.15GHz to 5.35GHz radio spectrum.
o Speed: Up to 54Mbps (actual throughput is closer to 22Mbps)
o Range: 50 feet
o Less prone to interference.
o More expensive.
o Because 802.11b and 802.11a use different radio technologies and portions of the spectrum, they are incompatible with one another. * 802.11b:
o Operates in the 2.4GHz radio spectrum.
o Speed: Up to 11Mbps
o Range: 100 feet
o Prone to interference (it shares airspace with cell phones, Bluetooth, security radios, and other devices).
o Least expensive wireless LAN specification.
o The Wireless Ethernet Compatibility Alliance (WECA) has done its part by certifying hundreds of products to make sure they work together.

* 802.11g:
o Operates in the 2.4GHz radio spectrum.
o Speed: Up to 54Mbps
o Range: 100 feet
o Prone to interference (it shares airspace with cell phones, Bluetooth, security radios, and other devices).
o
* 802.11n (Draft):
o Operates in the 2.4 or 5GHz radio spectrum
o Speed: Up to 700Mbs
o Range: 50 feet

o Because 802.11b and 802.11g use the same radio technologies and portions of the spectrum, they are compatible with one another. But because the 802.11n standard has yet to be ratified by WECA, it may not be completely compatible with 802.11b and 802.11g.

What is WiFi?

Wireless Standards - 802.11b, 802.11a, 802.11g, and 802.11n

802.11 explained
* 80211a
* 80211b
* 80211g
* 80211n

wireless local area network (WLAN). Many products conform to the 802.11a, 802.11b, 802.11g, or 802.11n wireless standards collectively known as Wi-Fi technologies.

802.11
In 1997, the Institute of Electrical and Electronics Engineers (IEEE) created the first WLAN standard. They called it 802.11 after the name of the group formed to oversee its development. Unfortunately, 802.11 only supported a maximum network bandwidth of 2 Mbps - too slow for most applications. For this reason, ordinary 802.11 wireless products are no longer manufactured.

802.11b
IEEE expanded on the original 802.11 standard in July 1999, creating the 802.11b specification. 802.11b supports bandwidth up to 11 Mbps, comparable to traditional Ethernet. 802.11b uses the same unregulated radio signaling frequency (2.4 GHz) as the original 802.11 standard. Vendors often prefer using these frequencies to lower their production costs. Being unregulated, 802.11b gear can incur interference from microwave ovens, cordless phones, and other appliances using the same 2.4 GHz range. However, by installing 802.11b gear a reasonable distance from other appliances, interference can easily be avoided.

* Pros of 802.11b - lowest cost; signal range is good and not easily obstructed
* Cons of 802.11b - slowest maximum speed; home appliances may interfere on the unregulated frequency band

802.11a
While 802.11b was in development, IEEE created a second extension to the original 802.11 standard called 802.11a. Because 802.11b gained in popularity much faster than did 802.11a, some folks believe that 802.11a was created after 802.11b. In fact, 802.11a was created at the same time. Due to its higher cost, 802.11a is usually found on business networks whereas 802.11b better serves the home market.

802.11a supports bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz. This higher frequency compared to 802.11b shortens the range of 802.11a networks. The higher frequency also means 802.11a signals have more difficulty penetrating walls and other obstructions.

Because 802.11a and 802.11b utilize different frequencies, the two technologies are incompatible with each other. Some vendors offer hybrid 802.11a/b network gear, but these products merely implement the two standards side by side (each connected devices must use one or the other).

* Pros of 802.11a - fast maximum speed; regulated frequencies prevent signal interference from other devices
* Cons of 802.11a - highest cost; shorter range signal that is more easily obstructed


802.11g
In 2002 and 2003, WLAN products supporting a newer standard called 802.11g emerged on the market. 802.11g attempts to combine the best of both 802.11a and 802.11b. So 802.11g supports bandwidth up to 54 Mbps, and it uses the 2.4 Ghz frequency for greater range. 802.11g is backwards compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa.

* Pros of 802.11g - fast maximum speed; signal range is good and not easily obstructed
* Cons of 802.11g - costs more than 802.11b; appliances may interfere on the unregulated signal frequency

802.11n
The newest IEEE standard in the Wi-Fi category is 802.11n. It was designed to improve on 802.11g in the amount of bandwidth supported by utilizing multiple wireless signals and antennas (called MIMO technology) instead of one.

When this standard is finalized, 802.11n connections should support data rates of over 100 Mbps. 802.11n also offers somewhat better range over earlier Wi-Fi standards due to its increased signal intensity. 802.11n equipment will be backward compatible with 802.11g gear.

* Pros of 802.11n - fastest maximum speed and best signal range; more resistant to signal interference from outside sources
* Cons of 802.11n - standard is not yet finalized; costs more than 802.11g; the use of multiple signals may greatly interfere with nearby 802.11b/g based networks.

Bluetooth

* Bluetooth is an alternative wireless network technology that followed a different development path than the 802.11 family. Bluetooth supports a very short range (approximately 10 meters) and relatively low bandwidth (1-3 Mbps in practice) designed for low-power network devices like handhelds. The low manufacturing cost of Bluetooth hardware also appeals to industry vendors. You can readily find Bluetooth in the netowrking of PDAs or cell phones with PCs, but it is rarely used for general-purpose WLAN networking due to the range and speed considerations.

* WiMax also was developed separately from Wi-Fi. WiMax is designed for long-range networking (spanning miles or kilometers) as opposed to local area wireless networking.

At a higher frequency, the range will be quite a bit less. At higher frequencies, any kind of wave, carries more energy, and has the ability to penetrate obstacles such as walls. The use of the word penetrate here does not imply passing straight through the obstacle and carrying on to its destination, but rather penetrating the obstacle and being absorbed. This is why higher frequencies have less range. Lower frequencies have a greater range because the lower energy of the low frequency wave allows it to bounce off of obstacles, and eventually make it to its target.





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