Wi-Fi networks use radio technologiesdefined by IEEE 802.11b, 802.11a, 802.11g or 802.11n (and 802.11y) . A Wi-Fi network can be used to connect computers to each other, to the Internet, and to wired networks using IEEE 802.3 or Ethernet. Wi-Fi networks operate in the unlicensed 2.4 and 5 GHz radio bands, with an 11 Mbps (802.11b) or 54 Mbps (802.11a or 802.11g) data rate or with products that contain both bands (dual band), so they can provide real-world performance similar to the basic 10BaseT wired Ethernet networks used in many offices.

While the wireless LAN provides many conveniences in today’s communication world, it also introduces unique security challenges, compare with the traditional wired network.  The early version of the Wi-Fi technology, IEEE 802.11b, tried to overcome the security issue by devising a user authentication and data encryption system known as Wired Equivalent Privacy, or WEP. Unfortunately, some compromises that were made in developing WEP have resulted in it being much less secure than intended.

Time Division Multiplex (TDM) is a technique of transmitting multiple digitized data, voice, and video signals simultaneously over one communication media by interleaving pulses representing bits from different channels or time slots. The basic channel bandwidth in the telecommunication is DS0, which channel width of 64kbps.

Wireless data networking is becoming a popular access technology for people to get connected into the wired local area network and the backbone network as well as to the voice network. In this article, only the data networking technologies, namely wireless local area network (WLAN), wireless personal networking (WPAN) and wireless metro area network technologies are introduced. Mobile wireless and 3G technologies will be overviewed in a different article.

July 25, 2008. Dr. Randy Pausch passed away today. He was a forever eacher for us all.

My thoughts and prayers go out to Randy's family. I wish them all well, knowing that their loved one made a very positive impact in the lives of millions of people worldwide.

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Did you watch the "Professor Randy Pausch's Last Lecture"? It is a great lecture about life! It was for 400 Carnegie Mellon students but millions are watching online now.

In this section, we are providing free ebooks on computing, networking and telecom technologies for download. We either obtained the permission from the copyright owner of the ebooks, or the copyright of these ebooks allows us to do such distribution. To further benefit the community, you are welcome to provide us more copyright-permitted titles for community download.

Articles about other VOIP Protocols:

Virtual Private LAN Services (VPLS) is a solution that can provide layer 2 Virtual Private Network (VPN) services over Ethernet networks. It uses a combination of Ethernet and MPLS to meet the needs of carriers and customers alike. VPLS allows customer networks at geographically diverse locations to communicate with each other as if they were in the same LAN. The WAN and MAN becomes transparent to all customer locations. Ethernet VPN based on VLPS and MPLS provides more benefits than other alternative layer 2 or 3 VPN technologies:

This section list all articles on hardware components of computer and networking devices and related technologies. 

This section lists articles related to TCP/IP technologies.