Now I completely understand your quest here
If the cable company in Cyprus can simply let you know what hardware/system they are using, it should be fairly straightforward. It's either DOCSIS or IPTV. Considering the multi-system HDTVs can handle essentially anything you throw at them, it should bring on few if any hurdles, compatiblity-wise. American HDTVs only handle 60Hz content, but Euro-HDTVs can handle both 50 & 60Hz content.
You can always take a peek at wikipedia for the basics, and more technical explanations if you read down in their bibliographies at the end of the article(s). Here are a few links to help you understand the differences:
DOCSIS (standard used by the cable companies in their boxes)
I see Cablenet is using DOCSIS3 in Cyprus. (Maybe that's the company you have in mind?) That's what we use here in the U.S. (Comcast, etc.) Whatever box they provide you with, it should work fine via HDMI with your multi-system HDTV.