cowboy me, 2.0: jose nazario beauty and the street

been hacking in tcl again

actually i've been hacking in a few languages. i wrote a milter plugin for Sendmail which implements a basic worm throttle. i contacted williamson about it, i'd like to release it but before i do i need to make sure its free of patent issues. very easy to implement, i did it in about one evening (two if you count testing and debugging).

i spent a good portion of tonight running a simulation i started last night (i didn't keep my laptop running all night). i wrote some code (tcl, using tcllib's graph module) to simulate work outbreaks.

above is a graph of the total number of sapphire hosts in a simple 3 node network over 600 time steps. i seeded one affected host in as1 and then let it go. the network is shown here:

and you can see how many victims there are per network and how easy it will be to find them.

the code has some bugs right now, and is nowhere near prime time. however, i'm finally reasonably happy with a first approximation modelling engine for a simple worm outbreak. bandwidth isn't infinite, for example, and the network space isn't flat. the real challenge is going to be making it more general purpose, for other people and also for the nature of worm outbreaks. by the way this took about 2 hours to implement and several more to run. i should improve its efficiency.

right now the agenda is: fix the known issues, instrument it a bit better for anyone else to use it (and myself, eg to set up arbitrary topologies or measure various aspects of the system), and run some simulations to answer a few questions i have.

and finally i updated the backend of MyBookmarkBlogger, using tcl and tcllib's htmlparse. once i'm confident its working reasonably well i'll turn it back on automatically. right now all updates have been manually filtered.

as much as i complain about tcl, when you find it suits your needs it's not half bad.



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Last modified: Tuesday, Dec 02, 2003 @ 10:35pm
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