Blog entries from June, 2010

Default deny is the security stance where anything that is not explicitly permitted, is forbidden. I use it all the time when writing code: extra form fields, ignore them, input doesn’t match, reject it, etc. It also fits in very nicely with defensive programming.

The opposite stance is default permit, number one of the six dumbest ideas in computer security.

In many aspects of my life I have been applying default permit. For example I used to buy up any vintage apple parts that were listed on ebay and I couldn’t walk past a secondhand book sale without buying a big handful of books.

Almost a year ago when I decided to downsize my computer collection I switched from default permit to default deny. I did this by starting to think about which items I wanted to keep, not about which items I could discard. The downsizing has continued in fits and starts, in some areas further than I had intended last year as I no longer have any PowerBooks or Newtons.

My other example above was books. I have a lot of books, specifically paperback novels, a mixture of fantasy, science fiction and action. But I have too many. Specifically too many to fit on the shelves so that they are doubled up.

A few weeks ago while listing some Apple parts on eBay I found that I was able to list items for free, so I grabbed quite a few books, photographed them and listed them. The books I selected first were mostly action and included a lot of spin-offs that were being mostly written by a secondary author, because of this I couldn’t see myself reading these books for a second time. Example of these include The Dreamers by David Eddings, the Dale Brown Dreamland collaborations, and Tom Clancy’s Net Force,

In hindsight this was default permit. I am going to get rid of a lot more books, but this time I will apply default deny. This means I will start by making a list of the books that I will read multiple times. This is a much smaller selective group that could contain everything by an author (Terry Pratchett is a clear candidate), or selected works from an author (early David Eddings, short story collections from Frederick Forsyth, Jeffrey Archer and Philip K. Dick).

Of course I will attempt to apply default deny to everything, not just computers and books, but I expect it will take time…

Following on from listing all of my PowerBook Duos on eBay, I have listed my Apple Newtons:

• Apple Newton MessagePad (original)
• Apple Newton MessagePad 130
• Apple Newton MessagePad 2000
• Apple Newton Keyboard
• Apple Newton MessagePad Charging Station
• Apple Newton eMate 300

Also interested in a camera?

• Apple QuickTake 100
• Apple QuickTake 200

Tonight at the camera club was another example of why I prefer competitions with a topic, in this case “slow shutter.”

Experimentation with a sheet of black perspex, a small lamp, a lego car and some black thread resulted in a highly commeded for:

I braved the threat of rain for about an hour on a bridge over the Eastern Freeway for a merit:

A failed attempt at startrails ended in playing around with glowsticks and lasers got me another merit:

My final image was from an impromptu road trip out to Noojee and the Toorongo Falls.

This was a week after I missed the club outing to the same location. I was lucky in that was late in the day and quite overcast (shortly after it poured with rain) which gave even lighting.

I also mounted the two prints (the waterfall and the freeway traffic) on white this time instead of black as I have done previously. For these images it made quite an improvement, but I think black does still have a place.

Unfortunately the next competition is open, but after that it will be “fences, gates and walls.”