A wireless router is a network device that performs the functions of a router but also includes the functions of a wireless access point. It can function in a wired LAN, a wireless only LAN, or a mixed wired/wireless network. Most current wireless routers have the following characteristics:
- -LAN ports, which function in the same manner as the ports of a network switch
- -A WAN port, to connect to a wider area network. The routing functions are filtered using this port. If it is not used, many functions of the router will be bypassed.
- -Wireless antennae. These allow connections from other wireless devices (NICs (network interface cards), wireless repeaters, wireless access points, and wireless bridges, for example).
The wireless functions operate as a separate nested "mini-LAN" within the router. The devices that connect wirelessly use the wireless router as their hub, and the wireless router presents that "mini-LAN" as a single device to the rest of the LAN.
Wireless routers, access points, and bridges are available that utilize each of the commonly used wireless frequencies (used in the Wireless-B, Wireless-A (and -G), and Wireless-N standards). The frequency bands for these wireless standards can be used license-free in most countries.
Wireless routers can work with devices in a point-to-point mode, but more commonly functions in a point to multipoint mode.
Wireless devices used that communicate with the wireless router must be set to the same service set identifier (SSID) and radio channel.
Netbooting Wirelessly
Unless you have a wireless card with a PXE-ROM chip built into it, it is not easy to directly netboot over a wireless connection. BIOS-based PXE algorithms usually only search for a wired NIC card to be used in a PXE netboot.
Some users have cleverly connected a Wireless Bridge (i.e. a wireless router or wireless access point set to the "bridge" mode) to the wired NIC card in their PC. The PC then netboots through the wired Ethernet NIC as usual, but the data is then transmitted from the NIC to the Wireless AP/Router connected to it and then wirelessly "across the bridge" to the central Wireless Router.
This solution works pretty well, but of course you must have two Wireless Access Points/Routers (one on each side of the "bridge"). Still, this is sometimes easier than running extra Ethernet cables throughout your home.
Wireless network
Wireless network refers to any type of computer network that is wireless, and is commonly associated with a telecommunications network whose interconnections between nodes is implemented without the use of wires, such as a computer network (a type of communications network).[1] Wireless telecommunications networks are generally implemented with some type of remote information transmission system that uses electromagnetic waves, such as radio waves, for the carrier and this implementation usually takes place at the physical level or "layer" of the network.
Types
Wireless Local Area Network (WLAN) is similar to other wireless devices and uses radio instead of wires to transmit data back and forth between computers on the same network.- Wi-Fi: Wi-Fi is a commonly used wireless network in computer systems which enable connection to the internet or other machines that have Wi-Fi functionalities. Wi-Fi networks broadcast radio waves that can be picked up by Wi-Fi receivers that are attached to different computers or mobile phones.
- Fixed wireless data : Fixed wireless data is a type of wireless data network that can be used to connect two or more buildings together in order to extend or share the network bandwidth without physically wiring the buildings together.
Wireless MAN
Wireless Metropolitan area networks are type of wireless network that connects several Wireless LANs.The IEEE 802-2001 standard describes a MAN as being:
A MAN is optimized for a larger geographical area than a LAN, ranging from several blocks of buildings to entire cities. MANs can also depend on communications channels of moderate-to-high data rates. A MAN might be owned and operated by a single organization, but it usually will be used by many individuals and organizations. MANs might also be owned and operated as public utilities. They will often provide means for internetworking of local networks. Metropolitan area networks can span up to 50km, devices used are modem and wire/cable
Implementation
Some technologies used for this purpose are ATM, FDDI, and SMDS. These older technologies are in the process of being displaced by Ethernet-based MANs (e.g. Metro Ethernet) in most areas. MAN links between LANs have been built without cables using either microwave, radio, or infra-red laser links. Most companies rent or lease circuits from common carriers due to the fact that laying long stretches of cable can be expensive.DQDB, Distributed Queue Dual Bus, is the Metropolitan Area Network standard for data communication. It is specified in the IEEE 802.6 standard. Using DQDB, networks can be up to 30 miles (50km) long and operate at speeds of 34 to 155 Mbit/s.
Several notable networks started as MANs, such as the Internet peering points MAE-West, MAE-East, and the Sohonet media network
Mobile devices networks
- Global System for Mobile Communications (GSM): The GSM network is divided into three major systems which are :the switching system, the base station system, and the operation and support system (Global System for Mobile Communication (GSM)). 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 where it needs to go (Global System for Mobile Communication (GSM)). This is used for cellular phones, is the most common standard and is used for a majority of cellular providers.[3]
- Personal Communications Service (PCS): PCS is a radio band that can be used by mobile phones in North America. Sprint happened to be the first service to set up a PCS.
- D-AMPS: D-AMPS, which stands for Digital Advanced Mobile Phone Service, is an upgraded version of AMPS but it is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
Wireless networks have had a significant impact on the world as far back as World War II. Through the use of wireless networks, information could be sent overseas or behind enemy lines easily, effieciently and more reliably. Since then wireless networks have continued to develop and its uses have significantly grown. Cellular phones are part of huge wireless network systems. People use these phones daily to communicate with one another. Sending information over seas is possible through wireless network systems using satellites and other signals to communicate across the world. Emergency services such as the police department utilize wireless networks to communicate important information quickly. People and businesses use wireless networks to send and share data quickly whether it be in a small office building or across the world.[4]
Another important use for wireless networks is as an inexpensive and rapid way to be connected to the Internet in countries and regions where the telecom infrastructure is poor or there is a lack of resources, like most developing countries.
Compatibility issues also arise when dealing with wireless networks. Different components not made by the same company may not work together, or might require extra work to fix compatibility issues. Wireless networks are typically slower than those that are directly connected through an Ethernet cable.
A wireless network is more vulnerable because anyone can try to break into a network broadcasting a signal. Many networks offer WEP -Wired Equivalent Privacy- security systems which have been found to be vulnerable to intrusion. Though WEP does block some intruders, the security problems have caused some businesses to stick with wired networks until security can be improved. Another type of security for wireless networks is WPA - Wi-Fi Protected Access. WPA provides more security to wireless networks than a WEP security set up. The use of firewalls will help with security breaches which can help to fix security problems in some wireless networks that are more vulnerable.
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