A matter of a regular Expression

Hello all,

I was working on a task asking to accept only BGP updates from AS100 and its
directly connected AS

Solution guide makes use of this regular expression ^100(_[0-9]+)?$

I used a simpler different solution ^100_[1-9]*$

I think my solution seems to work.

Can anyone confirm the difference between the 2 methods used and if one has any
advantage over the other

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Received on Mon Apr 13 2009 - 02:54:41 ART