With the intent of forming a trans-Europe numbering plan as an option (or then future movement) for anyone needing multi-national European telephone presence, the ITU allocated country calling code +388 as a subdivided, catch-all container for such services. This was designated the European Telephony Numbering Space or ETNS.
Although some ETNS numbers were assigned, few phone companies supported connecting calls to ETNS.
Because of limited support, and the belief that the need for ETNS was superseded by URIs, ETNS was suspended in 2005 and abolished in 2008. All ETS numbers were cancelled by the beginning of 2010. The +388 code was scheduled to be reclaimed by the ITU at the end of 2010;〔(http://www.ero.dk/etns )〕 as of late 2011 it was listed by ITU as "Group of countries, shared code."〔(List of ITU-T Recommendation E.164 assigned country codes as of 1 November 2011 )〕
See also list of country calling codes.
Geographically the +388 "country" code was an overlay on top of all the pre-existing, state-bounded country codes of the countries in Europe. Among "special" country codes, +388 was unique in that it was both supranational yet geographically bounded (other special codes, such as +881 and freephone +800, are completely international).
Instead of being subdivided geographically as in a typical numbering plan, the ETNS was intended to be subdivided by type of service or customer. It would therefore not have been possible to reverse engineer the location of an owner of an ETNS number based on the characteristics of the phone number. The numbers were also not allocated in blocks to individual carrier companies and were therefore intended to be portable. Carriers needed to have ETNS translation capability, or routing agreement with a carrier that did, in order for its customers to successfully call ETNS numbers.
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