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Playa phone at Burning Man

If you noticed a long break in the blogging, it's because I was at Burning Man. And while people do blog from Burning Man, it's not what you want to spend your time doing. I will have more entries in the future, but let me relate some stories of the network and the phone booth first.

Last year, we erected a free phone booth in the desert to great results. This year, it was going to be even better because of a plan for a new internet connection. In the past, John Gilmore had brought his satellite dish, which had all the latency and bandwidth limits of satellite. This year he splurged on getting a microwave link in, which will be even faster next year. Sadly, much of that money was wasted because we never got the "first mile" -- the on-playa 802.11 network -- operating at a satisfactory level. There was huge packet loss and jitter in most places, when it was up at all. Next time some of the money will go into better equipment and planning for the local network.

As such, the phone booth, located in our camp on 7:30, only worked intermittently and rarely with great voice quality. We eventually decided to sacrifice the aesthetic purity of a booth sitting in the desert, connected to nothing, and moved it on its wagon by trike to the center camp, home of the incoming microwave link. The we set it up on the street, with an ethernet wire snaking in. We were no longer wireless, but the voice quality was top notch. I wasn't able to spend much time with it but reports were that the line got very long at times.

In our own camp, you could tell if it was working or not based on whether there was a line. Even waiting for it to work was better than the 2-3 hour time investment of taking the bus to the phone booth in Gerlach.

Last year, I recounted the emotional experience people had using an unexpected and impossible phone to hear the voices of loved ones. This year, this was magnified by Katrina. I learned of Katrina, in fact, when people came to ask to use the phone to contact their relatives in NOLA. (Read on...)

Is strong crypto worse than weaker crypto? Lessons from Skype

A mantra in the security community, at least among some, has been that crypto that isn't really strong is worse than having no crypto at all. The feeling is that a false sense of security can be worse than having no security as long as you know you have none. The bad examples include of course truly weak systems (like 40 bit SSL and even DES), systems that appear strong but have not been independently verified, and perhaps the greatest villian, "security through obscurity" where the details of the security are kept secret -- and thus unverified by 3rd parties -- in a hope that might make them safer from attack.

On the surface, all of these arguments are valid. From a cryptographer's standpoint, since we know how to design good cryptography, why would we use anything less?

However, the problem is more complex than that, for it is not simply a problem of cryptography, but of business models, user interface and deployment. I fear that the attitude of "do it perfectly or not at all" has left the public with "not at all" far more than it should have.

An interesting illustration of the conflict is Skype. Skype encrypts all its calls as a matter of course. The user is unaware it's even happening, and does nothing to turn it on. It just works. However, Skype is proprietary. They have not allowed independent parties to study the quality of their encryption. They advertise they use AES-256, which is a well trusted cypher, but they haven't let people see if they've made mistakes in how they set it up.

This has caused criticism from the security community. And again, there is nothing wrong with the criticism in an academic sense. It certainly would be better if Skype laid bare their protocol and let people verify it. You could trust it more. Read on...

DHCP Option for street address, PSAP for VoIP E911

While for various reasons I believe that the efforts to enforce E911 requirements on Voice over IP phones are bogus and largely designed to make it harder for smaller players to compete with established companies, there is a legitimate need for ways to give your location to emergency services.

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802.11 broadcast of local info

On a recent roadtrip, I did some "wardriving" where you scan for 802.11 (wifi) access points. Today they are everywhere. The scanning program lists the network name (SSID) as well as other information like the model of access point and whether it has encryption on. Often the SSIDs are informative, with the names of families and companies. Mine is an web address that would let a neighbour contact me.

All this happens because most access points transmit a regular "beacon" packet which lists their SSID and other information needed to connect to them. Seeing that the SSIDs were sometimes interesting, I wondered if we might do much more with a special beacon.

This beacon would deliberately tell you a bit about the access or location. It would contain a mixed XML/HTML packet with a variety of useful fields and general text. These could range from simple descriptions ("This access point belongs to Joe Smith, I'm a programmer") to information ("On this site, Paul Revere stopped on his ride to consult with local minutemen") to street directions ("Turn right to get to highway 101, left for downtown") to, of course, advertising ("We sell fresh fruit and have a special on plums today.")

In other words, a replacement for signs and billboards and markers. And perhaps much more. Access points would also talk about themselves, declaring, for example, if the owner is offering open internet access for free or for fee, or has a local database of information, and what classes of information are in the main text. The local lattitude and longitude for those without a GPS could be useful, along with local map data in a compact form.

Users could quickly get a program for their laptop (such as Netstumbler) to read and display such virtual annotations to the world as they drive. Primarily for passengers to use, of course. Eventually dedicated boxes would become available, and onboard car computers and GPS units could understand the protocol. Mass market access points would include a set-up screen in their web interface to let the owner enter the information beacon text and enable it. (Today some APs have open source firmware and an energetic programmer could do this right away.)

All of this might be both useful and entertaining. Children might enjoy reading all the random bits of information that flow by and stop asking "are we there yet?" The journey can become the reward. (Of course remember to look out the window sometimes.)

I can imagine vendors making a cheap solar powered access point that, during the day at least, sends out information beacons as soon as enough power is stored in the capacitors to send one. These could operate on a small, cheap solar cell (the more power, the more frequent the beacon) and be placed anywhere. "I'm an oak tree!"

Below, I will get into some technical issues and discuss the unanswered question, which is how to avoid abuse by excessive advertisement, spam and falsehoods.

Double voice mail

Ok, I don't publish too many of my telecom ideas here since I am working on revolutionizing the phone call for my next business, but here's a simple one.

If you have a large carrier voice mail, such as the voice mail for a wireless company, you should notice if I call somebody and they are not simply busy, but in the act of leaving a voice mail for me. If so, you should break into their voice mail dialog and connect us.

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One fiber does it all

A short note, as I've been busy with a number of things including trying out PC based HDTV recording and mythtv, which I will write about shortly.

In a VoIP pricing debate, I calculated an interesting observation. Today we have voice codecs that can do very fine voice quality in about 25 kilobits. FM radio quality. Cell phone quality can be done in 7 kilobits. Anyway, that means all 200 million adult Americans could be on the phone at once and it would use 5 terabits.

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NA Wireless providers -- allow incoming VoIP for free!

We've seen the explosion in Voice over IP phone companies, using lower IP costs (and regulatory bypass) to offer very cheap long distance. Today, in the wholesale market, you can place VoIP calls to regular phone numbers in the major cities of the world for between 0.5 cents and 1 cent per minute. So cheap that companies are routinely offering people "unlimited" long distance plans for a flat monthly fee.

The rates are cheap, but they aren't yet free, so calls don't happen without contracts and plans and arrangements.

Here's something begging to be done: The cellular carriers in the USA and Canada should allow people calling in from the internet to call any cell phone for free.

This would cost them the tiny amount they get for terminating long distance calls to cell phones, but the end result would be their own customers billing more minutes. That's what they want (sort of.) They could release a free program for use on common PCs to call any cell phone. They could have a java applet or ActiveX control to make a web page to let you call any cell phone for free, just as they let you send an SMS from a web page for free. (If you have a headset with a mic, at least.)

But allowing free and open calling would encourage lots of innovating applications from the marketplaces. Smart PBXs would coordinate and connect with company cell phones over the internet. More advanced apps would link cell phones closer to PBX functions. People who use their cell as their home phone would have another reason to do it -- now all their friends can call free from VoIP phones or any PC. Companies like Vonage would offer free calls to cell phones even for people not on the unlimited plan.

802.11/SIP/Satellite free phone booth at Burning Man

One core reason I haven't blogged much in the last while is the flurry of activity regarding my annual trip to Burning Man. I've prepared a page about one of my too-many projects this year, which was to build an incongruous phone kiosk in the middle of the desert which worked and let you call anybody in the world for free. It was battery powered, and used 802.11 and Voice over IP combined with a satellite internet connection.

Down with PoIP

Voice over IP, a field I've been working in, has been generating some recent excitement. And that's appropriate.

However a lot of the talk is about something I consider the wrong direction. I call it PoIP, for PSTN over IP or worse, POTS over IP. (POTS, in turn, stands for Plain old Telephone Service.)

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