09-04-2011, 02:39 PM
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Wireless network
Introduction
Wireless network refers to any type of computer network that is not connected by cables of any kind. It is a method by which telecommunications networks and enterprise (business), installations avoid the costly process of introducing cables into to a building, or as a connection between various equipment locations. Wireless telecommunications networks are generally implemented and administered using a transmission system called radio waves. This implementation takes place at the physical level, (layer), of the network structure.
Types of wireless connections
Wireless PAN
Wireless Personal Area Networks (WPANs) interconnect devices within a relatively small area, generally within a persons reach. For example, both Bluetooth radio and invisible Infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications.[3] Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.[4]
Wireless LAN
A wireless local area network (WLAN) links two or more devices using a wireless distribution method, providing a connection through an access point to the wider internet. The use of spread-spectrum or OFDM technologies also gives users the mobility to move around within a local coverage area, and still remain connected to the network.
• Wi-Fi: "Wi-Fi" is a term used to describe 802.11 WLANs, although it is technically a declared standard of interoperability between 802.11 devices.
• Fixed Wireless Data: This implements point to point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link.
Wireless MAN
Wireless Metropolitan Area Networks are a type of wireless network that connects several Wireless LANs.
• WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard.
Wireless WAN
Wireless wide area networks are wireless networks that typically cover large outdoor areas. These networks can be used to connect branch offices of business or as a public internet access system. They are usually deployed on the 2.4 GHz band. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photo-voltaic solar panels or wind systems they can be stand alone systems.
Mobile devices networks
Further information: mobile telecommunications
With the development of smart phones, cellular telephone networks routinely carry data in addition to telephone conversations:
• Global System for Mobile Communications (GSM): The GSM network is divided into three major systems: the switching system, the base station system, and the operation and support system. The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred to where it needs to go. GSM is the most common standard and is used for a majority of cell phones.[6]
• Personal Communications Service (PCS): PCS is a radio band that can be used by mobile phones in North America and South Asia. Sprint happened to be the first service to set up a PCS.
• D-AMPS: Digital Advanced Mobile Phone Service, an upgraded version of AMPS, is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
Uses
File:Router Board 112 with U.FL-RSMA pigtail and R52 miniPCI Wi-Fi card.jpg
An embedded Router Board 112 with U.FL-RSMA pigtail and R52 mini PCI Wi-Fi card widely used by wireless Internet service providers (WISPs) in the Czech Republic.
Wireless networks continue to develop, usage has grown in 2010. Cellular phones are part of everyday wireless networks, allowing easy personal communications. Inter-continental network systems use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.
Another use for wireless networks is a cost effective means to connect to the Internet, in regions where the telecommunications infrastructure is both poor and lacking in resources, typically in rural areas and developing countries.
Compatibility issues also arise when dealing with wireless networks. Different devices may have compatibility issues, or might require modifications to solve these issues. Wireless networks are often typically slower than those found in modern versions of Ethernet cable connected installations.
A wireless network is more vulnerable, because anyone can intercept and sometimes divert a network broadcasting signal when point to point connections are used. Many wireless networks use WEP - Wired Equivalent Privacy - security systems. These have been found to be still vulnerable to intrusion. Though WEP does block some intruders, the security problems have caused some businesses to continue using wired networks until a more suitable security system can be introduced. The use of suitable firewalls overcome some security problems in wireless networks that are vulnerable to attempted unauthorized access.
Environmental concerns and health hazard
Starting around 2009, there have been increased concerns about the safety of wireless communications, despite little evidence of health risks so far.[7] The president of Lakehead University refused to agree to installation of a wireless network citing a California Public Utilities Commission study which said that the possible risk of tumors and other diseases due to exposure to electromagnetic fields (EMFs) needs to be further investigated.
Wireless network
Introduction
Wireless network refers to any type of computer network that is not connected by cables of any kind. It is a method by which telecommunications networks and enterprise (business), installations avoid the costly process of introducing cables into to a building, or as a connection between various equipment locations. Wireless telecommunications networks are generally implemented and administered using a transmission system called radio waves. This implementation takes place at the physical level, (layer), of the network structure.
Types of wireless connections
Wireless PAN
Wireless Personal Area Networks (WPANs) interconnect devices within a relatively small area, generally within a persons reach. For example, both Bluetooth radio and invisible Infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications.[3] Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.[4]
Wireless LAN
A wireless local area network (WLAN) links two or more devices using a wireless distribution method, providing a connection through an access point to the wider internet. The use of spread-spectrum or OFDM technologies also gives users the mobility to move around within a local coverage area, and still remain connected to the network.
• Wi-Fi: "Wi-Fi" is a term used to describe 802.11 WLANs, although it is technically a declared standard of interoperability between 802.11 devices.
• Fixed Wireless Data: This implements point to point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link.
Wireless MAN
Wireless Metropolitan Area Networks are a type of wireless network that connects several Wireless LANs.
• WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard.
Wireless WAN
Wireless wide area networks are wireless networks that typically cover large outdoor areas. These networks can be used to connect branch offices of business or as a public internet access system. They are usually deployed on the 2.4 GHz band. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photo-voltaic solar panels or wind systems they can be stand alone systems.
Mobile devices networks
Further information: mobile telecommunications
With the development of smart phones, cellular telephone networks routinely carry data in addition to telephone conversations:
• Global System for Mobile Communications (GSM): The GSM network is divided into three major systems: the switching system, the base station system, and the operation and support system. The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred to where it needs to go. GSM is the most common standard and is used for a majority of cell phones.[6]
• Personal Communications Service (PCS): PCS is a radio band that can be used by mobile phones in North America and South Asia. Sprint happened to be the first service to set up a PCS.
• D-AMPS: Digital Advanced Mobile Phone Service, an upgraded version of AMPS, is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
Uses
File:Router Board 112 with U.FL-RSMA pigtail and R52 miniPCI Wi-Fi card.jpg
An embedded Router Board 112 with U.FL-RSMA pigtail and R52 mini PCI Wi-Fi card widely used by wireless Internet service providers (WISPs) in the Czech Republic.
Wireless networks continue to develop, usage has grown in 2010. Cellular phones are part of everyday wireless networks, allowing easy personal communications. Inter-continental network systems use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.
Another use for wireless networks is a cost effective means to connect to the Internet, in regions where the telecommunications infrastructure is both poor and lacking in resources, typically in rural areas and developing countries.
Compatibility issues also arise when dealing with wireless networks. Different devices may have compatibility issues, or might require modifications to solve these issues. Wireless networks are often typically slower than those found in modern versions of Ethernet cable connected installations.
A wireless network is more vulnerable, because anyone can intercept and sometimes divert a network broadcasting signal when point to point connections are used. Many wireless networks use WEP - Wired Equivalent Privacy - security systems. These have been found to be still vulnerable to intrusion. Though WEP does block some intruders, the security problems have caused some businesses to continue using wired networks until a more suitable security system can be introduced. The use of suitable firewalls overcome some security problems in wireless networks that are vulnerable to attempted unauthorized access.
Environmental concerns and health hazard
Starting around 2009, there have been increased concerns about the safety of wireless communications, despite little evidence of health risks so far.[7] The president of Lakehead University refused to agree to installation of a wireless network citing a California Public Utilities Commission study which said that the possible risk of tumors and other diseases due to exposure to electromagnetic fields (EMFs) needs to be further investigated.
