Plug Me In
Ever Hear of a HomePlug Network? You Will

Source: http://www.pbs.org/cringely

By Robert X. Cringely

Last week's riff on how the coming ubiquity of wireless networks could lead to a new and better form of digital rights management brought out both supporters and detractors. The former were idealists and engineers, while the latter were cynics and businesspeople. Where will we get the bandwidth, they asked? What kind of person would allow others to muck around in their computer looking for CDs and movies? What kind of writer would even recommend it? Didn't I know that it's a cruel world, and no computer is safe without a firewall, galoshes, and a barbed wire perimeter?

It is a cruel world, I suppose, but everything we do requires facing that danger and calculating the risk. I wasn't advocating next week throwing a shareware peer-to-peer application on every PC in America. Mine was a big idea, one that feels inevitable to me, but even inevitable takes time. So I feel okay about that part of last week's column, but there is another part -- a part nobody thought to complain about or even notice -- where I feel now I was in grave error. I think now I got it wrong when I predicted the ubiquity of 802.11 networks. Oh, they'll still be everywhere -- Intel will see to that -- but I'm not sure they will be used exactly the way I predicted.

When the movie "Bonnie and Clyde" premiered 35 years ago, Newsweek movie critic David Ansen reviewed the film twice on successive weeks. The first time he saw "Bonnie and Clyde" as a violent B movie with little to recommend it other than its name stars. Then a week later, Ansen corrected himself and predicted "Bonnie and Clyde" would be a classic. In the intervening seven days, he saw the error in his thinking that had kept him from seeing how the film would change forever the way we would look at heroes in cinema. In his mind, the movie went from trivial to monumental, and it is to Ansen's credit that he was willing to admit his mistake. This story about "Bonnie and Clyde" came to mind when I realized that I had to make my own correction concerning 802.11 networks.

WiFi networks will become ubiquitous because Intel has plans to pull the technology right into its processors intended for notebook computers. But where I had it wrong, I now believe, was in my prediction that this would make WiFi the default home networking technology of the future. I no longer think that.

There are real problems with WiFi for home use. It is insecure, for one thing. My friend Paul, who recently moved to New York City, sent me an e-mail complaining about the difficulty of getting high-speed Internet service installed in Manhattan. He was able to send that message because his notebook computer detected a vulnerable WiFi network somewhere in the building. So he just logged right on, sharing without permission some unknown neighbor's bandwidth.

This insecurity becomes more difficult to fight in a network using products from several vendors. For example, my home network uses wireless access points from Apple, D-Link, and Linksys, and each vendor uses a different WEP access scheme. So the only way to get all these parts working together is to leave WEP turned off. The only security my network has, then, can be found in my use of static IP addresses and the fact that my nearest neighbor is half a mile away. That's not very secure.

And when WiFi works, it doesn't work that well. Remember that last week's column came about because I couldn't get a single WiFi access point to cover my entire house. I was defeated by a stainless steel refrigerator. Well, Max Levchin, CTO at PayPal, can't get a WiFi network running in his one bedroom apartment because the signals won't get through his reinforced concrete bedroom wall. My buddy Ira in Tokyo can't use WiFi at home for the same reason. And another friend in San Francisco admitted that his 1,850 square foot apartment on Nob Hill was, too, immune to WiFi, having walls that were just too thick.

Of course, this problem is one that will be fixed by Ultra Wide Band (UWB) networking, but UWB is still a couple years away from primetime.

Please understand that I am not suddenly saying that 802.11 networks have no purpose, just that their purpose is more limited than I had thought. WiFi is the only logical way to connect in public places. And as I proved last year with my 10 kilometer wireless DSL connection, WiFi has definite use for mid-range network links. But that doesn't make it ideal for home use. What is ideal for home use, I suddenly realized this week, is HomePlug power line networking.

This is the technology I used to build an Ethernet-to-Ethernet bridge from one end of my house to the other so I could extend my WiFi network. Setting up the bridge, however, didn't immediately reveal to me the power of Homeplug.

Homeplug products are just coming on the market from all the same vendors who sell WiFi products. HomePlug costs more than Ethernet if you ignore the cost of pulling cable. It costs slightly less than WiFi and about the same as HomePNA phone line networking. But HomePlug is more powerful than HomePNA specifically because we have electrical outlets in every room, and most homes don't have that many phone jacks. Power outlets are everywhere, meaning every home in America is already wired for HomePlug. This is a very powerful concept because it means the technology can be adopted at an incredibly fast rate. Just plug it in.

Cable costs have always been a factor in business networks. Early wireless vendors like RadioLAN liked to point out that the cost of pulling new cable -- any type of cable -- was more than $100 per foot in New York offices because of the high cost of union labor. HomePlug can make that same argument. The network is already there. And unlike WiFi and other wireless networks, HomePlug has no range or interference problems. It goes wherever the wire goes.

Now where the wire goes could surprise you, because HomePlug devices will work as long as they are on the same side of a power company transformer. In the U.S. an average of six houses share each transformer, which means your HomePlug network can extend next door or down the street. If you live in an apartment, your HomePlug network can cover the entire building.

This looks like a point of vulnerability, but I don't think it is. The Linksys bridges I installed use 56-bit DES encryption to keep private traffic private. What these HomePlug products can create, in fact, is a Virtual Private Network, an idea that I like a lot.

And there are advantages to having a networking technology that can go from house to house or apartment to apartment. Say I am a highrise landlord. By getting a $399 per month 1.5 megabit-per-second symmetrical business DSL account and plugging a single HomePlug bridge into the wall, I can offer perfectly fine and perfectly legal broadband service to the entire building. Sounds like a business to me.

What made me realize the power of HomePlug was when I noticed that I nearly always plug my notebook computer into the wall when I use it at home. Even in bed, I can't accept the poor battery performance of today's notebooks. A survey of my friends reveals that they do exactly the same thing at home. So if you are already plugged-in, why not use the network, too?

And yet HomePlug -- an industry standard supported by dozens of vendors -- is hardly being promoted at all. This is going to be an enormous business, yet right now it is almost invisible.

HomePlug networks are presently limited to 14 megabits-per-second and the network topology is exactly like the old Ethernet bus networks before we all bought switches. So there are bandwidth limits (no HDTV over HomePlug -- at least not yet) and very real limits to how many users can be on a single subnet. But if we are talking about half a dozen houses and a few dozen apartments, I don't think the constraints will be that noticeable. Besides, HomePlug, too, is scheduled to be available in faster variants in the future. Not only that, but HomePlug silicon will shortly appear in many smart appliances and digital telephones.

And it just plain works. When I install a network at my Mom's house next year, HomePlug will be the only way to go.

Source:

http://www.pbs.org/cringely/pulpit/pulpit20020815.html