I was somewhat excited to see a module that did something neat when the two previous posters mentioned Graph but after looking at it and the extensive documentation and no tutorials I thought this was too much...

The method I was thinking of is a hash of a hash; the key of the hash is all the IP's and the values are a hash with with your linked IP's.

my %network = (
    '1.2.3.4' => {'1.2.3.5' => undef,
                  '1.2.3.6' => undef,
                  '1.2.3.7' => undef },
    '1.2.3.5' => {'1.2.3.4' => undef,
                  '1.2.3.6' => undef,
                  '1.2.3.7' => undef },
    '1.2.3.6' => {'1.2.3.4' => undef,
                  '1.2.3.5' => undef,
                  '1.2.3.7' => undef },
    '1.2.3.7' => {'1.2.3.4' => undef,
                  '1.2.3.5' => undef,
                  '1.2.3.6' => undef },
);
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