security clearance
Hi
Probably they are doing a background check. Are you in research/new technology? If so, they may have held you under technology alert list. Call the consulate and find out if it is a check. If so, it might take a few weeks.
Check out the thread "cable clearance sent...what next". This has posts from quite a few people with similar situation (including me! however, it is all over and I am back now)
Good luck.
NIW03