I'd rather see that sort routine inlined in this case. As it stands, nasty subtle bugs can creep in with some sloppy maintenance. Say at some point someone has to add $VAR2 and perform similar sorting on it... and make the all too simple mistake of thinking they can add a line that reads:

my @result2 = sort custom keys %$VAR2;
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This is perfectly readable:

my @result = sort { 
        $VAR1->{$a}{network} cmp $VAR1->{$b}{network} 
    } keys %$VAR1;
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If it was something you had to do repeatedly, it would be better to wrap the whole sort in a sub...

sub keys_sorted_by_network { 
    my $h = shift; 
    sort { $h->{$a}{network} cmp $h->{$b}{network} } keys %$h;
}
my @result = keys_sorted_by_network($VAR1);
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