1.SIS II shall be composed of:
(a)a central system (Central SIS II) composed of:
(a)a technical support function (‘CS-SIS’) containing a database, the ‘SIS II database’,
a uniform national interface (NI-SIS);
(b)a national system (N.SIS II) in each of the Member States, consisting of the national data systems which communicate with Central SIS II. An N.SIS II may contain a data file (a ‘national copy’), containing a complete or partial copy of the SIS II database;
(c)a communication infrastructure between CS-SIS and NI-SIS (the Communication Infrastructure) that provides an encrypted virtual network dedicated to SIS II data and the exchange of data between SIRENE Bureaux as referred to in Article 7(2).
2.SIS II data shall be entered, updated, deleted and searched via the various N.SIS II systems. A national copy shall be available for the purpose of carrying out automated searches in the territory of each of the Member States using such a copy. It shall not be possible to search the data files of other Member States' N.SIS II.
3.CS-SIS, which performs technical supervision and administration functions, shall be located in Strasbourg (France) and a backup CS-SIS, capable of ensuring all functionalities of the principal CS-SIS in the event of failure of this system, shall be located in Sankt Johann im Pongau (Austria).
4.CS-SIS shall provide the services necessary for the entry and processing of SIS II data, including searches in the SIS II database. For the Member States which use a national copy CS-SIS shall:
(a)provide on-line update of the national copies;
(b)ensure synchronisation of and consistency between the national copies and the SIS II database;
(c)provide the operation for initialisation and restoration of the national copies.