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EMERGING MOBILE AND WIRELESS NETWORKS
Wireless and mobile networks are quickly becoming the networks of choice, not only because of large bandwidth, but due to the flexibility and freedom they offer.
Introduction
With the increasing use of small portable computers, wireless networks, and satellites, a trend to support computing on the move has emerged—this trend is known as mobile computing, also referred to as anytime/anywhere computing.
Mobile computing has several interesting and important applications for business (such as and e-commerce), telecommunications and personal communications, national defense (tracking troop movements), emergency and disaster management, real-time control systems, remote operation of appliances, and in accessing the Internet. Since a user may not maintain a fixed position in such environments, the mobile and wireless networking supports mobile users to communicate with other users (fixed or mobile).When dealing with different wireless networks, a universal mobile device should be able to select the network (LAN, the Internet, PCS, or satellite) that best meets user requirements.
Wireless and mobile networks have provided the flexibility required for an increasingly mobile workforce. ...
Wireless communications brings us back to a form of communications that is inherently natural to us. ... Human speech itself, despite its limited range, is wireless. ... Wireless
Wired and wireless networking can be distinguished in following key areas:
Ease of Installation: To run the Ethernet cables from each computer to another computer is time-consuming and difficult especially when computers sit in different rooms. Wi-Fi networks can be configured in two ways:
• "Ad hoc" mode through which wireless devices can communicate using peer-to- peer
• "Infrastructure" mode through which wireless devices can communicate with a central node which in turn can communicate with wired nodes on that LAN.
Total Cost: Ethernet cables, hubs and switches are very inexpensive, whereas Wireless stuff costs significantly more than the Ethernet products. ... Wireless LANs suffer a few more reliability problems than wired LANs. Noise and interference have more impact on systems design for wireless systems than on wired systems. ... As more wireless devices use the same WLAN performance degrades even further. ... Wireless LANs are less secure than wired LANs, because signals travel through the air and can easily be intercepted.
Channel Capacity: The channel capacity typically available in wireless systems is much lower than what is available in wired networks due to the limited spectrum available, power restrictions, and noise levels. ... Frequency allocation is required before building a wireless system. ... )
Wired and wireless Network
Mobile Vs Wireless Networks
Mobile users do not necessarily need to use wireless interfaces and wireless interfaces do not necessarily support mobility. A mobile user can simply connect to fixed networks using wired interfaces as he or she moves. Likewise, a fixed-location user might use a wireless interface (via a LAN) while sitting in an office. Therefore, mobile and wireless systems are not the same even but there is overlap. Mobile networks provide support how to maintain communication with mobility and kept track of the location. Wireless networks provide wireless interfaces to users (both mobile and stationary) by supporting bandwidth allocation and error-control functions.
Emerging Mobile and Wireless Networks
Mobile and wireless networks are experiencing significant progress in the form of :
• Wireless local area networks (WLANs)
• Wireless Asynchronous Transfer Mode (ATM) networks
• Wireless Local Loops (WLL)
• Satellite-based networks
• Mobile Internet Protocol (IP)
• Bluetooth
The following Table shows the Comparison of several Mobiles and Wireless Networks:
Issues Wireless LANs Wireless Loops Mobile IP Wireless ATM Satellites
Coverage Local Area Local or Metropolitan Wide Area Wide Area Wide Area
Bandwidth 1-20Mbps 1-20Mbps Network Dependent 1-20Mbps 19-2Kbps
Application Data/Voice Data/Voice Data/Voice All Data/Voice
Major Issues Limited area Interference Limited Applications Cost Initial Cost
Status In use Emerging Emerging Emerging Emerging
Wireless LANs
Wireless local area networks are designed to provide coverage in a small area, such as a building, hallway, park, or office complex by extending or replacing wired LANs (such as Ethernet).
Approximate Word count = 3090 Approximate Pages = 12.4 (250 words per page double spaced)
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