help in speciation

[Project IDSUGA]

hi
we're using galib2.4.5 revison B to build an IDS for
which the GA 
builds the rules.

We input behaviour as bit strings and we require rules
that use 
{0,1,#}.

The role of the GA is to take the huge knowledge base
and reduce it to 
a rule set that can accept the entire knowledge base,
without allowing 
spurious entries. Thus we intend the GA to work as a
classifier on the 
knowledge base. the GA is to be run offline and the
generated rules are 
to be used in an anomaly detection engine, assume
clean data is 
provided.

the fitness function takes into account the total
number of matches and 
gives a penalty for hashes(non linear penalty
function) and also takes 
into account the number of matches made versus the
number of matches 
possible(due to the presence of hashes, we dont want
extraneous area to 
be covered)

Our approach uses speciation : 
We use an Incremental GA with crowding, to prevent a
species to eat up 
others
we use goldberg style sharing, to pull down a species
with too many 
members
we use galib style (galib doc pg no : 96) restricted
mating with a 
random (UniformSelection) to encourage the formation
of other species/


the problem we are facing is that :
the final population is dominated by  a single
species, although other 
individuals do exist, there are no 'species', only
trash rules from the 
initial population that were not eliminated.


What can we do to generate multiple species that cover
different areas 
of the knowledge base? we want these to coexist. we
want a final 
population that consists of rules such that all areas
of the KB are covered, 
and the number of rules of each species is
proportional to the 
corresponding area in the knoweledge base.

The knowledge base we currently use is a very simple
one that contains 
only four distinct species.

Has someone tried to solve a similar problem? what was
the approach 
used?

please help.

thanks.

Jay
Anubhav
Manish
Sumeet



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