Wireless Network Technology

From WirelessAfrica
Revision as of 15:14, 18 November 2005 by Yusufk (talk | contribs) (Wireless Technology moved to Wireless Network Technology)

Wirless PAN

PAN or Personal Area Network describes connectivity of devices in the immediate space of the user. For example, the enablement of communication between a handheld device like a cellular phone and a nearby pc.

Bluetooth

UWB

Wireless LAN

LAN or Local Area Network, for example, an office area.

Wifi

IEEE 802.11 Standards

The following IEEE standards[3] and task groups exist within the IEEE 802.11 working group:

IEEE 802.11 - The original 1 Mbit/s and 2 Mbit/s, 2.4 GHz RF and IR standard (1999)

IEEE 802.11a - 54 Mbit/s, 5 GHz standard (1999, shipping products in 2001)

IEEE 802.11b - Enhancements to 802.11 to support 5.5 and 11 Mbit/s (1999)

IEEE 802.11c - Bridge operation procedures; included in the IEEE 802.1D standard (2001)

IEEE 802.11d - International (country-to-country) roaming extensions (2001)

IEEE 802.11e - Enhancements: QoS, including packet bursting (2005)

IEEE 802.11F - Inter-Access Point Protocol (2003)

IEEE 802.11g - 54 Mbit/s, 2.4 GHz standard (backwards compatible with b) (2003)

IEEE 802.11h - Spectrum Managed 802.11a (5 GHz) for European compatibility (2004)

IEEE 802.11i - Enhanced security (2004)

IEEE 802.11j - Extensions for Japan (2004)

IEEE 802.11k - Radio resource measurement enhancements

IEEE 802.11l - (reserved, typologically unsound)

IEEE 802.11m - Maintenance of the standard; odds and ends.

IEEE 802.11n - Higher throughput improvements

IEEE 802.11o - (reserved, typologically unsound)

IEEE 802.11p - WAVE - Wireless Access for the Vehicular Environment (such as ambulances and passenger cars)

IEEE 802.11q - (reserved, typologically unsound, can be confused with 802.1q VLAN trunking)

IEEE 802.11r - Fast roaming

IEEE 802.11s - ESS Mesh Networking (See: Mesh Standards)

IEEE 802.11T - Wireless Performance Prediction (WPP) - test methods and metrics

IEEE 802.11u - Interworking with non-802 networks (e.g., cellular)

IEEE 802.11v - Wireless network management

IEEE 802.11w - Protected Management Frames

Note - there is no standard or task group named "802.11x". Rather, this term is used informally to denote any current or future 802.11 standard, in cases where further precision is not necessary. (The IEEE 802.1X standard for port-based network access control, is often mistakenly called "802.11x" when used in the context of wireless networks.)

Note - 802.11F and 802.11T are recommendations, not standards and are capitalized as such.

Wireless MAN

MAN or Metropolitan Area Network describes networks large enough to service a city.

WiMax

1. WiMax MAC is very similar to bluetooth - there is a master/slave, AP/client relationship and the MAC layer creates dedicated time slots for clients which can enlarge and constrict. Very different to the contention based CSMA/CA model in WiFi which causes the typical collision and unfairness problems.

2. Working group in progress for mesh standard for WiMax. If they keep the master/client relationship with central arbitration ... mesh becomes tricky - I've seen the complexity with Bluetooth scatternets where you have to have multiple time sync points - I wonder if they will keep to the same MAC scheme for mesh. Searched all IEEE papers - no one has let this cat out of the bag

3. WiMax is is mainly defined at the MAC layer, it can run on many different PHY layers although OFDM seems to be the favoured choice at the moment.

4. There are two frequency bands being defined for WiMax 10 to 66GHz and 802.16a added support for 2 to 11GHz in the unlicensed frequency bands.

5. Claim distances of 50km but real world tests haven't gone beyond 5 to 8 km

6. Claim data rates of up to 70 Mbit/s but real world tests show data rates between 500kbit/s and 2 Mbit/s

WiBro

Wireless WAN

WAN or Wide Area Network describes large networks that typically cover areas as large as an entire country.

2.5G

GPRS

General Packet Radio System

EDGE

HSDPA

3G

CDMA

CDMA - Code Division Multiple Access

CDMA-2000

W-CDMA

4G

4G is a network of networks, it is a solution looking for a problem. Terminal has to accommodate converged radio networks. “The user wants to google cnn anytime, anywhere at the right cost having all security considered…” (IWS2005, summary of exec round table discussion on 4G).

Also described as an IP Ubiquitous Network.

OFDM