The Accidental Time Machine

Joe Haldeman does good work, and in general I have really liked his books. They’re easy to read, fun, and interesting. Better than that, they’re all quite different in the topics they cover, so he’s not in a rut. The only exceptions have been There Is No Darkness, which wasn’t very good and Forever Free, which I thought was lazily plotted. This book is no exception to the rule, and I really enjoyed it. One theme to Joe’s work that I am noticing is that the “sex scenes” are always anti-climatic, which is interesting to note.

I’d like to have heard more about the One Year War, but there is scope for that to be another separate book. I don’t think this book suffers from the lack of coverage, and its mostly tangentially interesting because I’d like to see how a society transforms itself in that way.

[award: nominee nebula_novel 2007]
[isbn: 978044101667;0441016162]

The witty worm with Vern Paxson

I’m sitting in a tech talk from Vern Paxson about the witty worm, and he’s just described how they could determine the state of the random number generator on infected machines when it sent probes to possible victims. Which gives you the uptime of the infected host, and they can see the distance between random numbers in the sequence, which means they can calculate the speed of the network link of infected machines, because they know the time distance between repeated probe attempts and how many packets were sent in between.

They can also determine the number of disks plugged into the infected machine, because a bug in the worm only re-seeded the random number generator when it trashed a disk block on the machine. It can only do that if that randomly selected disk exists.

The talk is being taped, so other people will be able to see it in a week or two.

Very cool.

Nerd link of the day

If you’re an ACM member, or read ACM transactions on computer systems, or have a corporate membership to the ACM portal, then you really should checkout Inferring Internet denial-of-service activity. It’s a surprisingly simple method of determining how common denial of service attacks really are on the Internet. Like all good ideas, it’s also really obvious once it’s been pointed out.

     author = {David Moore and Colleen Shannon and Douglas J. Brown and Geoffrey M. Voelker and Stefan Savage},
     title = {Inferring Internet denial-of-service activity},
     journal = {ACM Trans. Comput. Syst.},
     volume = {24},
     number = {2},
     year = {2006},
     issn = {0734-2071},
     pages = {115--139},
     doi = {},
     publisher = {ACM Press},
     address = {New York, NY, USA},