I don't know why, but about two years ago, I just stopped reading fiction. Before this I had been a ravenous consumer of fiction, mostly, sci-fi and thrillers. Yes I still read the traditional Christmas, Terry Pratchett book, as I have every year for the past, well...forever. Actually I came to Discworld very early on. I got The Colour of Magic and The Light Fantastic just after Equal Rites came out in hardback. So I was there first! Anyway I digress...
I picked up three of Dan Browns books today in a three for 2 offer, while Christmas shopping. I knew of course about the Da Vinci Code and Digital Fortress caught my eye, mainly because of the digital bit in the title. Reading the sleeve notes I saw that the story revolves around cryptography, a subject which fascinates me. So I bought both of the above titles along with Angles and Demons.
So enough of how I got the book, what do I think of it? Well it's early days yet, I'm only on page 103 of 613. 103 pages in one sitting is very good for me, yes the story has grabbed me, despite that the first few chapters, some of which where one page jobs, are obviously filling in background. However when we got to the technical bits, I started to feel a little disappointed. Unbreakable codes impossible? Complete and utter rubbish. I can make a completely unbreakable code simply by turning letters in numbers in sequence a =1, b =2 etc and then add all of the numbers together. A vola, one unbreakable code. okay it's not actually useful to any one, since you would need to know the original message for the code to have any meaning, but it is unbreakable.
There are however real world codes that are unbreakable, which are called one time pads. To make a one time pad, take one sheet of truly random numbers (hard to do). To encode your message turn in to numbers and the first letters number to the first number on the pad, then the second to the second and so on. Once you've encoded he message destroy the sheet. At the remote end the message is decoded in the reverse way. The problem is that the for the system to be truly secure, the pads must be disturbed securely and it's hard to receive, securely a one time pad when your behind enemy lines!
Okay so thats one technical flaw. Then we have the problem of Susan Fletchers email tracer. As soon as one of her special emails is received it sends a signal back to base and then erases it's self. Mmmm...how I ask my self. Assuming it was possible to make such a tracer that would work on any email system, with out knowing what that system is (it's not possible to do this by the way), I could connect to that mail server from any where in the world and use a pain text mail reader (or technically speaking I could telnet to port 110 on the server) and they would not know where I collected the mail from, only the server it arrived at. Yes I do concede that with modern mail clients (Outlook particularly) it might well be possible to do something like they describe. But if you where going to hide you wouldn't use Outlook to read your mail.
Oh and one more thing the machine capable of breaking codes on any kind with out prior knowledge of what the code is in hours, just doesn't exist (I hope!). Even with 3 million processors they might be able to break codes in 10's millions of years rather than 100's or 1000's of millions of years, but the machine would need to know the cypher in advance!
Okay rant over now and I feel better. I guess in order to make a good story some technical compromises must be made. I guess I feel a little cheated, since the review I saw made great play of all the technical details. I was hoping it would be more realistic. Having said this, I don't let these facts get in the way of enjoying a good story. No I just nit pick and gripe about them on my web site!