Wireless Technologies
Wireless technologies can be classified in different ways depending on their range. Each wireless technology is designed to serve a specific usage segment. The requirements for each usage segment are based on a variety of variables, including Bandwidth needs, Distance needs and Power.
Wireless Wide Area Network (WWAN)
This network enables you to access the Internet via a wireless wide area network (WWAN) access card and a PDA or laptop.
These networks provide a very fast data speed compared with the data rates of mobile telecommunications technology, and their range is also extensive. Cellular and mobile networks based on CDMA and GSM are good examples of WWAN.
Wireless Personal Area Network (WPAN)
These networks are very similar to WWAN except their range is very limited.
Wireless Local Area Network (WLAN)
This network enables you to access the Internet in localized hotspots via a wireless local area network (WLAN) access card and a PDA or laptop.
It is a type of local area network that uses high-frequency radio waves rather than wires to communicate between nodes.
These networks provide a very fast data speed compared with the data rates of mobile telecommunications technology, and their range is very limited. Wi-Fi is the most widespread and popular example of WLAN technology.
Wireless Metropolitan Area Network (WMAN)
This network enables you to access the Internet and multimedia streaming services via a wireless region area network (WRAN).
These networks provide a very fast data speed compared with the data rates of mobile telecommunication technology as well as other wireless network, and their range is also extensive.
Issues with Wireless Networks
There are following three major issues with Wireless Networks.
- Quality of Service (QoS) − One of the primary concerns about wireless data delivery is that, unlike the Internet through wired services, QoS is inadequate. Lost packets and atmospheric interference are recurring problems of the wireless protocols.
- Security Risk − This is another major issue with a data transfer over a wireless network. Basic network security mechanisms like the service set identifier (SSID) and Wireless Equivalency Privacy (WEP); these measures may be adequate for residences and small businesses, but they are inadequate for the entities that require stronger security.
- Reachable Range − Normally, wireless network offers a range of about 100 meters or less. Range is a function of antenna design and power. Now a days the range of wireless is extended to tens of miles so this should not be an issue any more.
Wireless Broadband Access (WBA)
Broadband wireless is a technology that promises high-speed connection over the air. It uses radio waves to transmit and receive data directly to and from the potential users whenever they want it. Technologies such as 3G, Wi-Fi, WiMAX and UWB work together to meet unique customer needs.
WBA is a point-to-multipoint system which is made up of base station and subscriber equipment. Instead of using the physical connection between the base station and the subscriber, the base station uses an outdoor antenna to send and receive high-speed data and voice-to-subscriber equipment.
WBA offers an effective, complementary solution to wireline broadband, which has become globally recognized by a high percentage of the population.
What is Wi-Fi ?
Wi-Fi stands for Wireless Fidelity. Wi-Fi is based on the IEEE 802.11 family of standards and is primarily a local area networking (LAN) technology designed to provide in-building broadband coverage.
Ad-hoc Wireless
An ad hoc network is one that is spontaneously formed when devices connect and communicate with each other. The term ad hoc is a Latin word that literally means “for this,” implying improvised or impromptu.
Ad hoc networks are mostly wireless local area networks (LANs). The devices communicate with each other directly instead of relying on a base station or access points as in wireless LANs for data transfer co-ordination. Each device participates in routing activity, by determining the route using the routing algorithm and forwarding data to other devices via this route.
Classifications of Ad Hoc Networks
Ad hoc networks can be classified into several types depending upon the nature of their applications. The most prominent ad hoc networks that are commonly incorporated are illustrated in the diagram below −
Wireless Technologies
Wireless technologies can be classified in different ways depending on their range. Each wireless technology is designed to serve a specific usage segment. The requirements for each usage segment are based on a variety of variables, including Bandwidth needs, Distance needs and Power.
Wireless Wide Area Network (WWAN)
This network enables you to access the Internet via a wireless wide area network (WWAN) access card and a PDA or laptop.
These networks provide a very fast data speed compared with the data rates of mobile telecommunications technology, and their range is also extensive. Cellular and mobile networks based on CDMA and GSM are good examples of WWAN.
Wireless Personal Area Network (WPAN)
These networks are very similar to WWAN except their range is very limited.
Wireless Local Area Network (WLAN)
This network enables you to access the Internet in localized hotspots via a wireless local area network (WLAN) access card and a PDA or laptop.
It is a type of local area network that uses high-frequency radio waves rather than wires to communicate between nodes.
These networks provide a very fast data speed compared with the data rates of mobile telecommunications technology, and their range is very limited. Wi-Fi is the most widespread and popular example of WLAN technology.
Wireless Metropolitan Area Network (WMAN)
This network enables you to access the Internet and multimedia streaming services via a wireless region area network (WRAN).
These networks provide a very fast data speed compared with the data rates of mobile telecommunication technology as well as other wireless network, and their range is also extensive.
Issues with Wireless Networks
There are following three major issues with Wireless Networks.
- Quality of Service (QoS) − One of the primary concerns about wireless data delivery is that, unlike the Internet through wired services, QoS is inadequate. Lost packets and atmospheric interference are recurring problems of the wireless protocols.
- Security Risk − This is another major issue with a data transfer over a wireless network. Basic network security mechanisms like the service set identifier (SSID) and Wireless Equivalency Privacy (WEP); these measures may be adequate for residences and small businesses, but they are inadequate for the entities that require stronger security.
- Reachable Range − Normally, wireless network offers a range of about 100 meters or less. Range is a function of antenna design and power. Now a days the range of wireless is extended to tens of miles so this should not be an issue any more.
Wireless Broadband Access (WBA)
Broadband wireless is a technology that promises high-speed connection over the air. It uses radio waves to transmit and receive data directly to and from the potential users whenever they want it. Technologies such as 3G, Wi-Fi, WiMAX and UWB work together to meet unique customer needs.
WBA is a point-to-multipoint system which is made up of base station and subscriber equipment. Instead of using the physical connection between the base station and the subscriber, the base station uses an outdoor antenna to send and receive high-speed data and voice-to-subscriber equipment.
WBA offers an effective, complementary solution to wireline broadband, which has become globally recognized by a high percentage of the population.
What is Wi-Fi ?
Wi-Fi stands for Wireless Fidelity. Wi-Fi is based on the IEEE 802.11 family of standards and is primarily a local area networking (LAN) technology designed to provide in-building broadband coverage.
Ad-hoc Wireless
An ad hoc network is one that is spontaneously formed when devices connect and communicate with each other. The term ad hoc is a Latin word that literally means “for this,” implying improvised or impromptu.
Ad hoc networks are mostly wireless local area networks (LANs). The devices communicate with each other directly instead of relying on a base station or access points as in wireless LANs for data transfer co-ordination. Each device participates in routing activity, by determining the route using the routing algorithm and forwarding data to other devices via this route.
Classifications of Ad Hoc Networks
Ad hoc networks can be classified into several types depending upon the nature of their applications. The most prominent ad hoc networks that are commonly incorporated are illustrated in the diagram below −
Wireless Sensor Network (WSN)
Wireless Sensor Network (WSN) is an infrastructure-less wireless network that is deployed in a large number of wireless sensors in an ad-hoc manner that is used to monitor the system, physical or environmental conditions.
Sensor nodes are used in WSN with the onboard processor that manages and monitors the environment in a particular area. They are connected to the Base Station which acts as a processing unit in the WSN System.
Base Station in a WSN System is connected through the Internet to share data.
WSN can be used for processing, analysis, storage, and mining of the data.
Applications of WSN:
- Internet of Things (IOT)
- Surveillance and Monitoring for security, threat detection
- Environmental temperature, humidity, and air pressure
- Noise Level of the surrounding
- Medical applications like patient monitoring
- Agriculture
- Landslide Detection Challenges of WSN:
- Quality of Service
- Security Issue
- Energy Efficiency
- Network Throughput
- Performance
- Ability to cope with node failure
- Cross layer optimization
- Scalability to large scale of deployment Components of WSN:
- Sensors:
Sensors in WSN are used to capture the environmental variables and which is used for data acquisition. Sensor signals are converted into electrical signals.
- Radio Nodes:
It is used to receive the data produced by the Sensors and sends it to the WLAN access point. It consists of a microcontroller, transceiver, external memory, and power source.
- WLAN Access Point:
It receives the data which is sent by the Radio nodes wirelessly, generally through the internet.
- Evaluation Software:
The data received by the WLAN AcessPoing is processed by a software called as Evaluation Software for presenting the report to the users for further processing of the data which can be used for processing, analysis, storage, and mining of the data.
Wireless Adhoc Network :
A wireless ad-hoc network is a wireless network deployed without any framework or infrastructure. This incorporates wireless mesh networks, mobile ad-hoc networks, and vehicular ad-hoc networks. It’s history could be traced back to the Defense Advanced Research Project Agency (DARPA) and Packet Radio Networks (PRNET) which evolved into the Survival Adaptive Radio Networks (SARNET) program. Wireless adhoc networks, in particular mobile ad-hoc networks (MANET), are growing very fast as they make communication simpler and progressively accessible. In any case, their conventions or protocols will in general be hard to structure due to topology dependent behavior of wireless communication, and their distributed and adaptive operations to topology dynamism. They are allowed to move self-assertively at any time. So, the network topology of MANET may change randomly and rapidly at unpredictable times. This makes routing difficult because the topology is continually changing and nodes cannot be expected to have steady data storage.
Applications:
- Data Mining
- Military battlefield
- Commercial Sector
- Personal area network or Bluetooth
Differences between Wireless Adhoc Network and Wireless Sensor Network :
| WIRELESS ADHOC NETWORK | WIRELESS SENSOR NETWORK |
| The medium used in wireless adhoc networks is radio waves. | The medium used in wireless sensor networks are radio waves, infrared, optical media. |
| Application independent network is used. | Application dependent network is used. |
| WIRELESS ADHOC NETWORK | WIRELESS SENSOR NETWORK |
| Hop-to-Hop routing takes place. | Query based (data centric routing) or location based routing takes place. |
| It is heterogeneous in type. | It is homogeneous in type. |
| The traffic pattern is point-to-point. | The traffic pattern is any-to-any, many-to-one, many-to-few, one-to-many. |
| Wireless router is used as an interconnecting device. | Application level gateway is used as an interconnecting device. |
| The data rate is high. | The data rate is low. |
| Supports common services. | Supports specific applications. |
| Traffic triggering depends on application needs. | Triggered by sensing events. |
| IP address is used for addressing. | Local unique MAC address or spatial IP is used for addressing. |