This is a telecommunications company called VinaKom. They make themselves sound larger than they actually are. I mean, they're based in Schaumburg, IL, how big can they be? Their sales reps range from obnoxious to abusive and don't seem to understand what "no" means.
These guys are nothing if they're not persistent. We've been trying to get them to stop calling for months, and they keep calling. They ask for me, the receptionists (we've been through several of them since my last post) asks them where they're calling from, and they just hang up.