Your results contain 4 solutions with the following criteria :

Corporate directories
Solution Smile rating Users rating Popularity
389 Directory Server 389 Directory Server 3.5 Smile 4.2 Visitors
19%   Popularity on the site
Apache Directory No rating No rating
13%   Popularity on the site
OpenDS No rating 3.2 Visitors
14%   Popularity on the site
OpenLDAP OpenLDAP 4.3 Smile No rating
42%   Popularity on the site