THE LATEST DEVELOPMENT IN NETWORKS AND COMMUNICATIONS
NAME : Hafizat b. Ahmad Jamalil
IC/NO : 951010-08-5591
CLASS : 4 ST
(Computer Network and Communication)
Today computer is available in many offices and homes and therefore there is a need to share data and programs among various computers with the advancement of data communication facilities. The communication between computers has increased and it thus it has extended the power of computer beyond the computer room. Now a user sitting at one place can communicate computers of any remote sites through communication channel. The aim of this chapter is to introduce you the various aspects of computer network.
2.0 MOBILE COMPUTING
Mobile Computing is an umbrella term used to describe technologies that enable people to access network services anyplace, anytime, and anywhere. Ubiquitous computing and nomadic computing are synonymous with mobile computing. Information access via a mobile device is plagued by low available bandwidth, poor connection maintenence, poor security, and addressing problems. Unlike their wired counterparts, design of software for mobile devices must consider resource limitation, battery power and display size. Consequently, new hardware and software techniques must be developed.
2.2 SPECIFICATION, SERVIS AND FREQUENCIES OF MOBILE COMPUTING
Mobile computing used to be exclusively a matter of dragging a laptop computer around,* plus various adapters and other widgets. “Road warriors” have more choices now. Of course, USB thumb drives, also called USB flash drives, are probably the benchmark technology for mobile computing these days; before you think about other methods, check if you can do it cheaper and easier with a thumb drive.
Mobility services can be classified into three groups. First there are services designed to overcome common restrictions of mobile computing, which arise mainly from the slowness, insecurity and instability of wireless or analogous connection lines utilized by the mobile user. These services are called common mobility services (CMS). The second group of services handles the management and administration of mobile users moving around and connecting their portables to networks at different places. These mobility management services (MMS) include tasks such as the authentication of users, accounting and billing issues or profiling of the users’ habits. The tasks necessary to adapt certain existing applications to mobile usage are implemented by high level services, which are called special mobility services(SMS). Special mobility services adapt existing services to the mobile conditions. For example to allow remote database access over a wireless connection line one has to take special care of possible frequent connection losses especially in the context of the state of the database. Viewing services as distinct building blocks, we are able to sketch an architecture for a “mobility services enhanced system”.
Bluetooth is an industrial specification for wireless personal area networks (PANs). Bluetooth provides a way to connect and exchange information between devices such as mobile phones, laptops, PCs, printers, digital cameras, and video game consoles over a secure, globally unlicensed short-range radio frequency. The Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group.Bluetooth technology relies on two things, a radio frequency technology and the protocol software enabling it to transmit data to other devices. Bluetooth-capable devices can transmit data to other devices not within the line of sight of the user.
3.0 INTERNET TECHNOLOGY AND SERVICES
Voice Over IP is a telephone service that uses the Internet as a global telephone network. Many companies, including Vonage, 8×8 and AT&T (CallVantage), typically offer calling within the country for a fixed fee and a low per-minute charge for international. Broadband Internet access (cable or DSL) is required, and regular house phones plug into an analog telephone adapter (ATA) provided by the company or purchased from a third party.
A blog is a lot like a journal except it is generally intended to be read by others. The topics for blogs vary greatly; some being about day to day activities and others taking a more corporate or political slant. There is no defined or widely accepted format and so blogs range from one liners that the author adds every few hours to relatively long, well thought out arguments for or against a topic of interest.
4.0 TYPE OF NETWORK
A Personal Area Network (PAN) is a computer network used for communication among computer devices (including telephones and personal digital assistants) close to one person. The devices may or may not belong to the person in question. The reach of a PAN is typically a few meters. PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the Internet (an uplink). Personal area networks may be wired with computer buses such asUSB and FireWire. A wireless personal area network (WPAN) can also be made possible with network technologies such as IrDA and Bluetooth.
Short for (Virtual Private Network), VPN is a type of network that allows a user to connect to a network through a tunneling protocol and access internal internet and intranet web sites and e-mail. Virtual Private Networks are commonly used to allow an employee with a large company to connect to the company’s intranet.
A Wireless Local Area Network, sometimes referred to as LAWN ( local area wireless network ) is one in which a mobile user can connect to a local area network (LAN) through a wireless (radio) connection. The IEEE 802.11 group of standards specify the technologies for wireless LANs. 802.11 standards use the Ethernetprotocol and CSMA/CA (carrier sense multiple access with collision avoidance) for path sharing and include an encryption method, the Wired Equivalent Privacy algorithm. A personal area network.
WiMax is the industry term for a long-range wireless networking standard. WiMax technology has the potential to deliver high-speed Internet access to rural areas and other locations not serviced by cable or DSL technology. WiMax also offers an alternative to satellite Internet services.WiMax technology is based on the IEEE 802.16 WANcommunications standard. WiMax signals can function over a distance of several miles / kilometers. Data rates for WiMax can reach up to 75 megabits per second (Mb/s). A number of wireless signaling options exist ranging anywhere from the 2 GHz range up to 66 GHz.
Mobile computing (like the peer to peer transaction model did) brings about a new paradigm of distributed computing in which communication may be achieved through wireless networks and users can compute even as they relocate from one support environment to another. The impact of mobile computing on systems design goes beyond the networking level and directly effects data management. Although being a relatively new area, mobile data management has attracted a lot of research efforts, motivated by both a great market potential and by many challenging research problems