NETWORKING AND WIMAX
NETWORKING AND WIMAX
- A network is basically all the components (hardware and software) involved in connecting computers across small and large distances.
- Networks are used to provide an easy access to information, thus increasing productivity for the users.
LOCAL AREA NETWORK (LAN)
- Local Area Network (LAN) is used to connect the devices which are geographically located very close to each other, like in Home, Building itself or Campus environment. LANs are designed to allow resource sharing between personal computer and workstation.
- Shared resources can be Hardware (Printer, database), software (application programs) or data. LAN network may be very simple depending upon the need and type of technology used. LAN network may be just two computers and a printer, or in an organization where hundreds of computers are interconnected.
- Today LAN networks mostly used are Ethernet, Fast Ethernet (FE), Gigabit (GE) Ethernet, Token ring and FDDI (Fibre Distributed Data Interface). But the most preferred are Ethernet and Fast Ethernet.
WIDE AREA NETWORK (WAN)
- Wide Area Network (WAN) is used to connect the devices which are geographically located at large distances. WAN can be used to connect two or more LANs together, that may be geographically separated.
- A WAN can be as complex as the backbones that connect the internet. There are 2 types of WAN: switched WAN and point to point WAN.
- Switched WAN connects the end system, which usually comprises a router (internet working connecting device) that connects to another LAN or WAN.
- The point to point WAN is normally a leased line connection which is provided by telephone or cable TV provider that connects home computer or a small LAN to an internet service provider (ISP). This type of WAN is used to provide an internet access. NETWORKING AND WIMAX
METROPOLITAN AREA NETWORK (MAN)
- Metropolitan Area Network (MAN) is a hybrid between LAN and WAN. Like WAN, MAN usually connects two LANs in same geographical area like two buildings in a city. MAN normally covers area inside the city.
- Whereas WAN usually gives low to medium speed, MAN provides high speed connection such as T1 (1.54 Mbs).
- A good example of MAN is part of the telephone company network that can provide a high speed DSL line to the customer.
STORAGE AREA NETWORKS (SANS)
- Storage area networks (SANs) provide a high-speed infrastructure to move data between storage devices (like disk drives, disk controllers, and any necessary cabling) and file servers.
- This infrastructure can be dedicated to just these devices or can include other devices. In this network, fibre channels are used for the connection.
- A fibre channel is an optical cable that connects the file server, disk controllers, and hard drives at rates exceeding 1 gigabit per second (Gbps).
- Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances (using short-wavelength radio transmissions in the ISM band from 2400-2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security.
- Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 bands (1 MHz each; centered from 2402 to 2480 MHz) in the range 2,400-2,483.5 MHz (allowing for guard bands).
- Because the Bluetooth devices use a radio (broadcast) communications system, they do not have to be in visual line of sight of each other
- Bluetooth provides a secure way to connect and exchange information between devices such as faxes, mobile phones, telephones, laptops, personal computers, printers, Global Positioning System (GPS) receivers, digital cameras, and video game consoles. NETWORKING AND WIMAX
WI-Fl | NETWORKING AND WIMAX
- Wi-Fi (Wireless Fidelity) is a popular technology that allows an electronic device to exchange data wirelessly (using radio waves) over a computer network, including highspeed Internet connections.
- “Wifi” is a trademark of the Wi-Fi Alliance and the brand name for products using the IEEE 802.11 family of standards.
- A device that can use Wi-Fi (such as a personal computer, video game console, Smartphone, tablet, or digital audio player) can connect to a network resource such as the Internet via a wireless network access point.
- Such an access point (or hotspot) has a range of about 20 meters (65 feet) indoors and a greater range outdoors. Hotspot coverage can comprise an area as small as a single room with walls that block radio waves or as large as many square miles — this is achieved by using multiple overlapping access points.
- It can operate at 2.4GHz and 5GHz frequency bands. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block.
- Wi-Fi allows cheaper deployment of local area networks (LANs). The spaces where cables cannot be run(such as outdoor areas and historical buildings) can host wireless LANs.
- Wi-Fi Protected Access encryption (WPA2) is considered secure, provided a strong passphrase is used.
BLUETOOTH VERSUS WI-Fl
- Bluetooth and Wifi have some similar applications: setting up networks, printing, or transferring files. Wifi is intended as a replacement for cabling for general local area network access in work areas.
- This category of applications is sometimes called wireless local area networks (WLAN). Bluetooth was intended for portable equipment and its applications. The category of applications is outlined as the wireless personal area network (WPAN).
- Bluetooth is a replacement for cabling in a variety of personally carried applications in any setting and also works for fixed location applications such as smart energy functionality in the home (thermostats, etc.).
- Wi-Fi is a wireless version of a common wired Ethernet network, and requires configuration to set up shared resources, transmit files, and to set up audio links (for example, headsets and hands-free devices).
- Wi-Fi uses the same radio frequencies as Bluetooth, but with higher power, resulting in higher bit rates and better range from the base station.
WIMAX | NETWORKING AND WIMAX
- WiMAX (Worldwide interoperability for Microwave Access) is a wireless communications standard (IEEE 802.16 now known as Fixed WiMax) designed to provide 30 to 40 megabit-per-second data rates, with the 2011 update providing up to 1 Gbit/s for fixed stations.
- It is a part of a “fourth generation,” or 4G, of wireless-communication technology. WiMax far surpasses the 30-metre wireless range of a conventional Wifi local area network (LAN), offering a metropolitan area network with a signal radius of about 50 km.
- WiMax offers data-transfer rates that can be superior to conventional cable-modem and Digital Subscriber Line (DSL) connections, however, the bandwidth must be shared among multiple users and thus yields lower speeds in practice.
- There is no uniform global licensed spectrum for WiMAX, however the WiMAX Forum has published three licensed spectrum profiles: 2.3 GHz, 2.5 GHz and 3.5 GHz, in an effort to drive standardisation and decrease cost.
USES OF WIMAX
The bandwidth and range of WiMAX make it suitable for the following potential applications:
- Providing portable mobile broadband connectivity across cities and countries through a variety of devices.
- Providing a wireless alternative to cable and digital subscriber line (DSL) for “last mile” broadband access.
- Providing data, telecommunications (VolP) and IPTV services.
- Providing a source of Internet connectivity as part of a business continuity plan.
WIMAX VERSUS WI-Fl
- WiMAX is a long range system, covering many kilometres that uses licensed or unlicensed spectrum to deliver connection to a network, in most cases the Internet. Wi-Fl uses unlicensed spectrum to provide access to a local network and is more popular in end user devices.
- WiMAX uses a quality of service (QoS) mechanism based on connections between the base station and the user device. Each connection is based on specific scheduling algorithms.
- Whereas Wi-Fi uses contention access i.e. all subscriber stations that wish to pass data through a wireless access point (AP) are competing for the AP’s attention on a random interrupt basis.
- This can cause subscriber stations distant from the AP to be repeatedly interrupted by closer stations, greatly reducing their throughput.
- Although Wi-Fi and WiMAX are designed for different situations, they are complementary. WiMAX network operators typically provide a WiMAX Subscriber Unit which connects to the metropolitan WiMAX network and provides Wi-Fi within the home or business for local devices (e.g., Laptops, Wi-Fi Handsets, smartphones) for connectivity.
- This enables the user to place the WiMAX Subscriber Unit in the best reception area (such as a window), and still be able to use the WiMAX network from any place within their residence. NETWORKING AND WIMAX