There is no legal way of watching BBC One/BBC Two/ITV/C4/C5 outside of the UK apart from the cable companies in Benelux, Switzerland etc. who have a formal agreement with UK broadcasters to retransmit their services. (Unless you are a member of UK armed forces...)
The BBC only negotiate UK and Ireland Public Service Rights for content they broadcast - be that bought-in or co-produced shows, shows they commission from independent production companies (which is most BBC drama these days), and music, archive, stills, talent etc. they include in their own productions. A key element to this is 'Public Service'. Once the BBC start selling content commercially, the rules change radically... (Their Public Service Rights contracts include a small clause that allows for small-scale Benelux/Switzerland 'cable rights') It is totally against the contracts the BBC have signed to make their content available outside the UK - in fact it is now incumbent on the BBC to mitigate illegal viewing I believe (by blocking commercial VPN providers)
The BBC negotiate separate deals on content to allow their shows to be re-sold (in some cases re-editing them to remove music, stills, archive they can't afford to commercially licence) overseas or on their non-UK commercial channels (BBC Brit, BBC Knowledge, BBC Entertainment etc.)
Implementing an internationally iPlayer that the BBC can legally operate is a non-trivial task, and would cost a significant amount of money. The experimental International iPlayer service (I think it ran in Australia) wasn't a success...
Deeply dull - but if you have an IPTV service available outside the UK offering you BBC One, BBC Two, ITV, C4 or C5 - it's very likely to be an illegal service...