This　paper　proposes　Architecture　of　Centralized　Management　and　Three-layer　Interconnection　(CMTIA),　which　aims　to　enhance　the　interconnection　security　of　a　High　Security　Level　Information　System　(HSLIS).　Centralized　management　is　the　core　of　this　architecture.　In　this　architecture,　all　system　entities　must　be　controlled　in　a　centralized　manner.　Before　connecting　to　other　entities　in　the　system,　each　entity　needs　to　map　their　identifier　to　a　corresponding　identifier　that　will　be　monitored　during　the　interconnection　period.　This　process　is　called　identity　mapping,　and　an　interconnection　policy　is　set　up　in　this　step.　Three-layer　interconnection　is　defined　for　the　structure　of　the　architecture.　HSLIS　is　the　first　layer,　Safe　Interconnection　Component　is　the　second　layer,　which　is　used　to　protect　data　delivering,　finally　the　third　layer,　called　a　Crosslevel　Security　Management　system,　is　used　to　complete　the　identity　mapping　process　for　the　entities.　The　paper　also　provides　a　solution　for　analyzing　the　policy　collision　during　the　identity　mapping,　which　includes　a　collision　detection　model　in　order　to　prevent　the　collision.　This　solution　is　based　on　the　tree-structure　theory.