WOW. No offense but, WOW...
First off, John-117 is a SNCO (Staff Noncommissioned Officer). Also, every branch of the military has NCOs/SNCOs. NCOs/SNCOs are Serviceman that have not received their rank by way of Warrant or Commission. For instance, enlisted ranks: Corporals (E-4s) and Sergeants (E-5s) are NCOs, and Gunnery Sergeants (E-7s) and Master Gunnery Sergeants (E-9s) are SNCOs.
[spoiler]Im using the U.S.M.C. Ranking system, so it's a bit different form the navies, but you can get the gist of it.[/spoiler]
-ShadowWolf
[url=http://en.m.wikipedia.org/wiki/United_States_Marine_Corps_rank_insignia]Here's a link to a Wiki page that explains the ranking structure of the U.S.M.C.[/url]
Like I said, it's a little different form the naives, but you can get the basics from it.