my @unsorted = <DATA>;

my @sorted =
  map{ $_->[0] } 
  sort{ $a->[1] <=> $b->[1] } 
  map { [$_, get_fourth($_) ] } 
  @unsorted;

sub get_fourth {
    local $_ = shift; 
    /\d+\.\d+\.\d+\.(\d+)/;
  return $1; 
}

print "@sorted";

__DATA__
10.194.196.55 heckyll
10.194.196.57 txwl013w
10.194.196.61 krios
10.194.196.62 stasis # dial up server
10.194.196.63 nnocdts01 # sparc 5 in wan rm
10.194.196.65 libra
10.194.196.66 legato-school
10.194.196.67 txwlxdbs nnocs002a
10.194.196.46 chqnocp01 # Laser 4MV by Joe Blow
10.194.196.47 chqnocp02
10.194.196.49 nnocrpt01
10.194.196.64 saturn
10.194.196.50 nnocgw001
10.194.196.52 nnocs002
10.194.196.53 wslkms02 wslknms0
10.194.196.54 nnocws001