If you run a web site of reasonable popularity, you probably get invitations to sign up for ad networks from time to time. They want you to try them out, and will sometimes talk a great talk about how well they will do.

I always tell them "put your money where your mouth is -- guarantee at least some basic minimum during the trial."

Most of them shut up when I ask for that, indicating they don't really believe their own message. I get enough that I wrote a page outlining what I want, and why I want it -- and why everybody should want it.

Hard disks fail. If you prepared properly, you have a backup, or you swap out disks when they first start reporting problems. If you prepare really well you have offsite backup (which is getting easier and easier to do over the internet.)

One way to protect yourself from disk failures is RAID, especially RAID-5. With RAID, several disks act together as one. The simplest protecting RAID, RAID-1, just has 2 disks which work in parallel, known as mirroring. Everything you write is copied to both. If one fails, you still have the other, with all your data. It's good, but twice as expensive.

RAID-5 is cleverer. It uses 3 or more disks, and uses error correction techniques so that you can store, for example, 2 disks worth of data on 3 disks. So it's only 50% more expensive. RAID-5 can be done with many more disks -- for example with 5 disks you get 4 disks worth of data, and it's only 25% more expensive. However, having 5 disks is beyond most systems and has its own secret risk -- if 2 of the 5 disks fail at once -- and this does happen -- you lose all 4 disks worth of data, not just 2 disks worth. (RAID-6 for really large arrays of disks, survives 2 failures but not 3.)

Now most people who put in RAID do it for more than data protection. After all, good sysadmins are doing regular backups. They do it because with RAID, the computer doesn't even stop when a disk fails. You connect up a new disk live to the computer (which you can do with some systems) and it is recreated from the working disks, and you never miss a beat. This is pretty important with a major server.

But RAID has value to those who are not in the 99.99% uptime community. Those who are not good at doing manual backups, but who want to be protected from the inevitable disk failures. Today it is hard to set up, or expensive, or both. There are some external boxes like the "readynas" that make it reasonably easy for external disks, but they don't have the bandwidth to be your full time disks.

RAID-5 on old IDE systems was hard, they usually could truly talk to only 2 disks at a time. The new SATA bus is much better, as many motherboards have 4 connectors, though soon one will be required by blu-ray drives.

I do enough photography that people ask me for advice on cameras. Some time ago I wrote an article about what lenses should I buy for a Canon DSLR which has turned out to be fairly popular. The thrust of that article, by the way, is to convince you that there is only minimal point in buying a DSLR that can changes lenses and getting only one lens for it, even if you plan to get another lens later (after your camera has depreciated plenty without using its real abilities.)

Recently, I wrote about thedata deposit box, an architecture where applications come to the data rather than copying your personal data to all the applications.

Let me examine some more of the pros and cons of this approach:

Recently we at the EFF have been trying to fight new rulings about the power of U.S. customs. Right now, it's been ruled they can search your laptop, taking a complete copy of your drive, even if they don't have the normally required reasons to suspect you of a crime. The simple fact that you're crossing the border gives them extraordinary power.

We would like to see that changed, but until then what can be done? You can use various software to encrypt your hard drive -- there are free packages like truecrypt, and many laptops come with this as an option -- but most people find having to enter a password every time you boot to be a pain. And customs can threaten to detain you until you give them the password.

There are some tricks you can pull, like having a special inner-drive with a second password that they don't even know to ask about. You can put your most private data there. But again, people don't use systems with complex UIs unless they feel really motivated.

What we need is a system that is effectively transparent most of the time. However, you could take special actions when going through customs or otherwise having your laptop be out of your control.

A brunch was planned for my mother's house on Sunday, but being 2,500 miles distant, I decided to try to attend by videoconference. Recently Skype has started supporting what it calls a "high quality" videoconference, which is 640x480 at 24 to 30 frames per second. At its base, that's a very good resolution, slightly better than broadcast TV.

This requires fairly modern hardware, which my mother doesn't have. It needs a dual-core processor to be able to compress the video in real time, and a decently fast processor to decompress it. It wants 384K of upstream bandwidth, but ideally even more, which in theory she has but not always. It demands Windows XP. And artificially it demands one of three of Logitech's newest and most expensive webcams, the Orbit AF or the Quickcam Pro for Notebooks or Pro 9000 for desktops. These are the same camera in 3 packages -- I took the Orbit AF which also includes a pan/tilt motor.

Skype's decision to only work with these 3 cameras presumably came from a large kickback from Logitech. Admittedly these are very nice webcams. They are true-HD webcams that can native capture at 1600x1200. They are sharp and better in low light than most webcams, and they come with a decent built in microphone that appears as a USB audio device -- also good. But they aren't the only cameras capable of a good 640x480 image, including many of Logitech's older high-end webcams. They retail for $100 or more, but via eBay sellers I got the Orbit AF for about $75 shipped and the Pro for Notebooks shipped quickly within Canada for $63. Some versions of Skype allow you to hack its config file to tell it to do 640x480 with other quality cameras. That is easy enough for me, but I felt it was not something to push on the relatives quite yet. On the Mac it's your only choice.

Testing on my own LAN, the image is indeed impressive when bandwidth is no object. It is indeed comparable to broadcast TV. That's 4 times the pixels and twice the framerate of former high-end video calls, and 16 times the pixels of what most people are used to. And the framerate is important for making the call look much more natural than older 10fps level calls.

A recent story today about discussions for an official defense Botnet in the USA prompted me to post a question I've been asking for the last year. Are some of the world's botnets secretly run by intelligence agencies, and if not, why not?

Here's my latest assembled panorama, of the main square of Munich, known as Marienplatz, taken from the St. Peter's Church bell tower just to the south.

It seems that half the programs I try and install under Windows want to have a "daemon" process with them, which is to say a portion of the program that is always running and which gets a little task-tray icon from which it can be controlled. Usually they want to also be run at boot time. In Windows parlance this is called a service.

I learned today that there is an exhibit about my father in the famous creation museum near Cincinnati. This museum is a multi-million dollar project set up by creationists as a pro-bible "natural history" museum that shows dinosaurs on Noah's Ark, and how the flood carved the Grand Canyon and much more. It's all completely bullocks and a number of satirical articles about it have been written, including the account by SF writer John Scalzi.

I'm scanning my documents on an ADF document scanner now, and it's largely pretty impressive, but I'm surprised at some things the system won't do.

Double page feeding is the bane of document scanning. To prevent it, many scanners offer methods of double feed detection, including ultrasonic detection of double thickness and detection when one page is suddenly longer than all the others (because it's really two.)

PCs can go into standby mode (just enough power to preserve the RAM and do wake-on-lan) and into hibernate mode (where they write out the RAM to disk, shut down entirely and restore from disk later) as well as fully shut down.

I've been ranting of late about the dangers inherent in "Data Portability" which I would like to rename as BEPSI to avoid the motherhood word "portability" for something that really has a strong dark side as well as its light side.

But it's also important to come up with an alternative. I think the best alternative may lie in what I would call a "data deposit box" (formerly "data hosting.") It's a layered system, with a data layer and an application layer on top. Instead of copying the data to the applications, bring the applications to the data.

A data deposit box approach has your personal data stored on a server chosen by you. That server's duty is not to exploit your data, but rather to protect it. That's what you're paying for. Legally, you "own" it, either directly, or in the same sense as you have legal rights when renting an apartment -- or a safety deposit box.

Your data box's job is to perform actions on your data. Rather than giving copies of your data out to a thousand companies (the Facebook and Data Portability approach) you host the data and perform actions on it, programmed by those companies who are developing useful social applications.

As such, you don't join a site like Facebook or LinkedIn. Rather, companies like those build applications and application containers which can run on your data. They don't get the data, rather they write code that works with the data and runs in a protected sandbox on your data host -- and then displays the results directly to you.

To take a simple example, imagine a social application wishes to send a message to all your friends who live within 100 miles of you. Using permission tokens provided by you, it is able to connect to your data host and ask it to create that subset of your friend network, and then e-mail a message to that subset. It never sees the friend network at all.

Been getting a bunch of calls from reporters this weekend. Our good friend spam turns 30 in a couple of days, and a few years ago I did some research and became an authority on the history of the term and the phenomenon. Since everybody else is doing it, I though I should point to my various articles on the history of spam, as well as some updates I just wrote for the 30th.

I've spoken about the Web 2.0 movement that is now calling itself "data portability." Now there are web sites, and format specifications and plans are underway to make it possible to quickly export the personal data you put on one social networking site to another. While that sounds like a good thing -- we like interoperability, and cooperation, and low barriers to entry on new players -- I sometimes seem like a lone voice warning about some of the negative consequences of this.

Ok, this would be a cool application for iPhones, Pocket PC and the like -- a dialer which presents an old style rotary phone dial, and you have to put your finger in it and spin it around the center, and then it slowly twists back and plays the sound of a dial returning. A bit like how you control an iPod, but slower.

Completely useless, other than for having fun and explaining to kids why we call it "dialing" a phone.

With sadness I must report the passing of William C. Tate, my stepfather, on Thursday. Bill and my mother met and fell in love when I was a young teenager. He was a neighbour, and I had met him, and even stayed over at his house with his son before they would meet, which is a bit unusual. He was kind and generous and supported her and our family for many decades. While he died from cancer, it came upon him quite suddenly and he was fortunately strong until near the end.

Ok, admit it, who likes blogging in to a vacuum. You want to know how many people are actually reading your blog.

I have created a simple Perl script that scans your blog's log file and attempts to calculate how many people read the blog and the RSS feeds.

You can download the feed reader script. I release it under GPL2.

Recently, while keynoting the Freedom 2 Connect conference in Washington, I spoke about some of my ideas for fiber networks being built from the ground up. For example, I hope for the day when cheap kits can be bought at local stores to fiber up your block by running fiber through the back yards, in some cases literally burying the fiber in the "grass roots."