The Engineer's Notebook

This week I want to bring you an informational topic about thebroadband wireless technologies known as WiMax and Wi Mesh. Nothing newor extraordinary today, but certainly an interesting piece ofinformation. Also, I am inspired by the WiMax World USA Conference and Expothat is going to take place in Boston, MA, from October 10 to October12, 2006. This is an extraordinary event where the biggest WiMaxplayers will be present to show us the future.

Up to now we haveenjoyed three different types of Internet access: telephone connection,wireline wideband, and wireless wideband represented mainly by Wi-Fi(wireless fidelity) and its related technologies such as Bluetooth andothers. Wi-Fi, which is based on the Standard IEEE 802.11,is a technology that works in limited areas (short ranges) and lackcapabilities to support new technologies such as VoIP or the newestIPTV (television over IP, or packet TV).

Enter now WiMax (Wordwide Interoperability for Microwave Access). This point-to-multipoint wireless technology, based on the new Standard IEEE 802.16,provides wireless communication at higher speed than Wi-Fi and forlarger ranges (up to 70 Mbps in a range of over 30 miles). A group ofindustry leaders (Nortel, Nokia,and others) decided in 2001 to createthis Standard. Five years later, in 2006, we are starting to see thefruits of this effort. WiMax is being implemented now and manymanufacturers are selling wireless devices WiMax Ready. By theend of 2006, is expected, must of our Wi-Fi devices will be replaced byWiMax devices and we will see a big step in the quality of wirelesscommunication.

Now enters into play Wi-Mesh (wirelessmesh). Because WiMax is a point-to-multipoint technology it is suitableto be used in mesh network topologies. A mesh network routs messagesbetween nodes in an arrangement or topology where transmittingstations are all connected to each others (just like nodes in a spiderweb, or like the telephone system). The communication is heavilyredundant and very seldom messages are lost for lack of routing. TheWi-Mesh Standards are being implemented by a group of industry leaders(headed, again, by Nortel) that in 2005 created the Wi-Mesh Alliance (WiMA)with the purpose of implementing WiMax in mesh networks. This idea willallow us all to enjoy wireless connection without any glitch, at highspeed and for ranges limited only by the deployment of the mesh.Several wireless providers (WiMax ready, of course!) can join the meshby connecting their stations to the network. In this way the wirelessrange is extended in proportion to the number of WiMax networks sharingthe mesh.

What does this mean for us, the users? You'll be ableto travel from New York to Buffalo (not in winter, of course) andduring the whole trajectory use your PDA, your micro computer or yourcell phone to browse the Internet or to watch the New York Yankees winthe World Series without any disruption. You'll be able to watch TV,make telephone calls, manage your Blog, connect to your office usingVPN technology, send e-mails, pay your bills or watch your dog in thekennel. All this while you are traveling, or from any place under themesh. Whole countries will be connected with this technology. It isonly a matter of time (or a matter of legislation).

Keep an eye on 2007 to start seeing these new extraordinary events.

The weekly challanges:

To participate in the weekly challenges Send your answers directly to me.

Good luck!

1. Challenge No. 3: What is the largest n-digit number which is also an exact n^th power?
2. Challenge No. 4: (Thischallenge is a Mensa puzzle; difficult.) Four doctors, a surgeon, adentist, an obstetrician, and a psychiatrist, have offices on the lowerfour floors of Medical Center building. Two are females, and two aremales, and each has a secretary of the opposite sex.
   
• Dr. Adams sent his secretary, Fran, down to the dentist's office with a bill for his appendectomy.
• Dr. Crane's secretary is engaged to Jean, and goes up to her office to have lunch every day.
• Dr. Davis is Pat's uncle. Pat goes down to Dr. Crane's office on the floor below once a week for treatment.
• Dr. Beard and Lynn both have red hair.

Can you tell the names, specialties, secretaries, and floors of the four doctors?