Technology Trends
Standards, Standards, and More Standards: At present, globally there are two main types of WLAN—802.11a and 802.11b—based on the standards established by the Institute of Electrical and Electronics Engineers (IEEE). The latter has been around for years and is the most widely adopted, while the former was introduced more recently and is in the nascent stage of acceptance by equipment vendors. The significant differences between the two are that 802.11a offers a faster connection than 802.11b and operates on spectrum that is less cluttered than 802.11b. Then, there are newer variations on these two offerings, such as 802.11g, 802.11e and 802.11i, which in essence are enhancements to the existing standards, offering greater compatibility, flexibility and security to Wi-Fi networks. Theoretically, 802.11b offers a throughput of 11 Mbps (though for all practical purposes, it is closer to 5.5 Mbps) and operates on the 2.4 GHz band, while 802.11a offers a connection speed of 54 Mbps and runs on the 5 GHz band. In India, the 802.11b variant of WLAN is permitted for use inside campuses without a licence.

l 802.11g: The 802.11g standard is a combination technology that is compatible with 802.11b and uses the 2.4 GHz band with a data rate comparable to that of 802.11a. As 802.11a runs on the 5 GHz band, which is regulated in India and is unlikely to be offered to private enterprises for use at least in the near future, its deployment is out of the question. So, enterprises can look forward to deploying 802.11g. Besides offering five times more throughput than 802.11b, 802.11g is also backwards compatible with 802.11b, enabling an access point built for 802.11g to connect 802.11b-based devices also. A laptop with 802.11b capability and a tablet PC with 802.11g, for instance, can thus use the same base station.

l 802.11b: 802.11b wireless networking consists of the stations or hubs, access points, and ports. A station (STA) is a network node that is equipped with a wireless network device. A personal computer with a wireless network adapter is known as a wireless client (laptops using wireless PCI cards). Wireless clients can communicate directly with each other or through a wireless access point (AP). Wireless clients are mobile. A wireless access point is a wireless network node that acts as a bridge between STAs and a wired network. The wireless AP is similar to a cellular phone network’s base station.

Wireless clients communicate with both the wired network and other wireless clients through wireless Aps, which are not mobile and act as peripheral bridge devices that extend a wired network. A port is a channel of a device that can support a single point-to-point connection. For IEEE 802.11b, a port is an association, a logical entity, over which a single wireless connection is made. A typical wireless client with a single wireless network adapter has one port and can support only one wireless connection. A typical wireless AP has multiple ports and can simultaneously support multiple wireless connections. The logical connection between a port on the wireless client and the port on a wireless AP is a point-to-point bridged LAN segment—similar to an Ethernet-based network client that is connected to an Ethernet switch.