802.11b wireless standard

802.11b wireless standard

The IEEE 802.11 standard defines the use of the two lower levels of the OSI architecture ( physical and data link layers ), specifying their operating standards in a WLAN (Wireless Local Area Network) or Wireless Local Area Networks . Today its versions 802.11a, 802.11b and 802.11g are used to provide connectivity in homes, offices and commercial establishments.

Summary

[ hide ]

  • 1 A bit of history
    • 1 Wi-Fi technology
  • 2 Description of the standard for Wi-Fi networks IEEE 802.11b
    • 1 Channel frequencies 802.11b
  • 3 Conclusions
  • 4 References
  • 5 External Links

A little history

The technology wired or wireless (wireless) is a term used to describe telecommunications in which electromagnetic waves (instead of wire) carry the signal over part or the entire path of communication . The first wireless transmitters were born in the early 20th century using radiotelegraphy ( Morse code ). Later, as modulation allowed voices and music to be transmitted through radio , the medium was called radio . With the advent of television, fax , data communication, and more efficient use of a larger portion of the spectrum , the term wireless has been resurrected.

 

Wireless LAN networks

Common examples of wireless equipment in use today include:

  • Mobile phones , which allow collectivity between people.
  • The Global Positioning System (GPS), which allows cars, ships and planes to check their location anywhere on earth.
  • Wireless computer peripherals , such as mice , keyboards, and printers , which can also be connected to a computer via wireless.
  • Cordless phones, shorter in range than mobile phones .
  • Remote controls (for television , video , garage doors, etc.) and some hi-fi systems.
  • Baby monitors, these devices are simplified radio units that transmit / receive within a limited range.
  • TV via satellite , allowing viewers from almost anywhere, select from hundreds of channels.
  • LAN networks wireless, provide flexibility and reliability for users of computers .

Wireless technology is developing rapidly, and it is increasingly present in the lives of people around the world. In addition, more and more people trust this technology directly or indirectly.

Technology Wi-Fi

The most popular wireless router is WiFi because it is the most used to access the Internet from anywhere there is an access point ( Access Point or AP ), especially in laptops and PDAs with a WiFi card . This is the device that meets the set of standards (IEEE 802.11 standard) for WLAN (Wireless Local Area Network – wireless local area network). The standard IEEE 802.11 is a frequency of Radio developed by the IEEE(Institute of Electrical and Electronics Engineers – Institute of Electrical and Electronic Engineers), and most operating systems support it, as well as many of the latest generation laptops, cell phones / mobiles , consoles, printers and other peripherals . The types of WiFi communication are based on the different classes of IEEE standards , most of the products of the b specification being of the g:

 

New Standard Wireless AC

  • 11a
  • 11b
  • 11g
  • 11n [1]
  • 11ac
  • 11ad

Description of the standard for Wi-Fi networks IEEE 802.11b

In July of 1999 , the IEEE expands the 802.11 creating the 802.11b specification, which has a theoretical maximum speed transmission of 11 Mbit / s, comparable to an Ethernet traditional, but because of the space occupied by the encoding of the protocol CSMA / CD (Carrier Sense Multiple Access / Collision Detect), in practice the maximum transmission speed is approximately 5.9 Mbit / s for TCP and 7.1 Mbit / s for UDP . [2] The 802.11b uses the same frequency of radius than traditional 802.11 (2.4GHz). The problem is that as this is a frequencyWithout regulation, interference could be caused by microwave ovens , mobile phones and other appliances operating on the same frequency . However, if 802.11b installations are at a reasonable distance from other elements, this interference is easily avoidable. In addition, manufacturers prefer to lower the cost of their products, even if this means using an unregulated frequency .

Advantage:

  1. Low cost, very good signal range and difficult to obstruct.
  2. It offers quality of service (QOS) security [3].

Disadvantages:

  1. Low maximum speed, support of a low number of users at the same time and produces interference in the 2.4 GHz band, such as microwave ovens , Bluetooth devices [4], baby monitors and cordless telephones.
  2. On the other hand, 802.11b standard products are not compatible with 802.11a standard products because they operate on different frequency bands .

In the following table we see the characteristics of this network . [5]

Standard features 802.11b
Wavelength frequency 2.4GHz (2.400-2.4835 in North America)
Data bandwidth 11Mbps, 5Mbps, 2Mpbs, 1Mbps
Security measures WEP – Wireless Equivalency Protocol in combination with Forward Spread Spectrum
Optimal Operating Range 50 meters inside, 100 meters outside
Adapted for a specific purpose or for a type of device Laptops , desktops where wiring is difficult, PDAs

Channel frequencies 802.11b

For 802.11b, there is only one radio model that is used worldwide. The following table shows the 802.11b channel assignments. [6]

Channel id World (GHz)
1 2,412
2 2,417
3 2,422
4 2,427
5 2,432
6 2,437
7 2,442
8 2,447
9 2,452
10 2,457 1
eleven 2,462 1

Note 1 : France is restricted to these channels.

Conclusions

The 802.11b standard, since its development in 1999 , as a direct extension of the modulation technique defined in the original 802.11 standard, has been one of the most widely used. Its spectacular increase in throughput (volume of information that flows through data networks ) compared to the original standard; Along with substantial price reductions, it has led to the rapid acceptance of 802.11b as the ultimate wireless LAN technology .

802.11b wireless standard

The IEEE 802.11 standard defines the use of the two lower levels of the OSI architecture ( physical and data link layers ), specifying their operating standards in a WLAN (Wireless Local Area Network) or Wireless Local Area Networks . Today its versions 802.11a, 802.11b and 802.11g are used to provide connectivity in homes, offices and commercial establishments.

Summary

[ hide ]

  • 1 A bit of history
    • 1 Wi-Fi technology
  • 2 Description of the standard for Wi-Fi networks IEEE 802.11b
    • 1 Channel frequencies 802.11b
  • 3 Conclusions
  • 4 References
  • 5 External Links

A little history

The technology wired or wireless (wireless) is a term used to describe telecommunications in which electromagnetic waves (instead of wire) carry the signal over part or the entire path of communication . The first wireless transmitters were born in the early 20th century using radiotelegraphy ( Morse code ). Later, as modulation allowed voices and music to be transmitted through radio , the medium was called radio . With the advent of television, fax , data communication, and more efficient use of a larger portion of the spectrum , the term wireless has been resurrected.

 

Wireless LAN networks

Common examples of wireless equipment in use today include:

  • Mobile phones , which allow collectivity between people.
  • The Global Positioning System (GPS), which allows cars, ships and planes to check their location anywhere on earth.
  • Wireless computer peripherals , such as mice , keyboards, and printers , which can also be connected to a computer via wireless.
  • Cordless phones, shorter in range than mobile phones .
  • Remote controls (for television , video , garage doors, etc.) and some hi-fi systems.
  • Baby monitors, these devices are simplified radio units that transmit / receive within a limited range.
  • TV via satellite , allowing viewers from almost anywhere, select from hundreds of channels.
  • LAN networks wireless, provide flexibility and reliability for users of computers .

Wireless technology is developing rapidly, and it is increasingly present in the lives of people around the world. In addition, more and more people trust this technology directly or indirectly.

Technology Wi-Fi

The most popular wireless router is WiFi because it is the most used to access the Internet from anywhere there is an access point ( Access Point or AP ), especially in laptops and PDAs with a WiFi card . This is the device that meets the set of standards (IEEE 802.11 standard) for WLAN (Wireless Local Area Network – wireless local area network). The standard IEEE 802.11 is a frequency of Radio developed by the IEEE(Institute of Electrical and Electronics Engineers – Institute of Electrical and Electronic Engineers), and most operating systems support it, as well as many of the latest generation laptops, cell phones / mobiles , consoles, printers and other peripherals . The types of WiFi communication are based on the different classes of IEEE standards , most of the products of the b specification being of the g:

 

New Standard Wireless AC

  • 11a
  • 11b
  • 11g
  • 11n [1]
  • 11ac
  • 11ad

Description of the standard for Wi-Fi networks IEEE 802.11b

In July of 1999 , the IEEE expands the 802.11 creating the 802.11b specification, which has a theoretical maximum speed transmission of 11 Mbit / s, comparable to an Ethernet traditional, but because of the space occupied by the encoding of the protocol CSMA / CD (Carrier Sense Multiple Access / Collision Detect), in practice the maximum transmission speed is approximately 5.9 Mbit / s for TCP and 7.1 Mbit / s for UDP . [2] The 802.11b uses the same frequency of radius than traditional 802.11 (2.4GHz). The problem is that as this is a frequencyWithout regulation, interference could be caused by microwave ovens , mobile phones and other appliances operating on the same frequency . However, if 802.11b installations are at a reasonable distance from other elements, this interference is easily avoidable. In addition, manufacturers prefer to lower the cost of their products, even if this means using an unregulated frequency .

Advantage:

  1. Low cost, very good signal range and difficult to obstruct.
  2. It offers quality of service (QOS) security [3].

Disadvantages:

  1. Low maximum speed, support of a low number of users at the same time and produces interference in the 2.4 GHz band, such as microwave ovens , Bluetooth devices [4], baby monitors and cordless telephones.
  2. On the other hand, 802.11b standard products are not compatible with 802.11a standard products because they operate on different frequency bands .

In the following table we see the characteristics of this network . [5]

Standard features 802.11b
Wavelength frequency 2.4GHz (2.400-2.4835 in North America)
Data bandwidth 11Mbps, 5Mbps, 2Mpbs, 1Mbps
Security measures WEP – Wireless Equivalency Protocol in combination with Forward Spread Spectrum
Optimal Operating Range 50 meters inside, 100 meters outside
Adapted for a specific purpose or for a type of device Laptops , desktops where wiring is difficult, PDAs

Channel frequencies 802.11b

For 802.11b, there is only one radio model that is used worldwide. The following table shows the 802.11b channel assignments. [6]

Channel id World (GHz)
1 2,412
2 2,417
3 2,422
4 2,427
5 2,432
6 2,437
7 2,442
8 2,447
9 2,452
10 2,457 1
eleven 2,462 1

Note 1 : France is restricted to these channels.

Conclusions

The 802.11b standard, since its development in 1999 , as a direct extension of the modulation technique defined in the original 802.11 standard, has been one of the most widely used. Its spectacular increase in throughput (volume of information that flows through data networks ) compared to the original standard; Along with substantial price reductions, it has led to the rapid acceptance of 802.11b as the ultimate wireless LAN technology .

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