The ULE Specification documentation is available on the web server of ETSI (European Telecommunications Standards Institute). Please download at www.etsi.org. DECT/ULE Physical Layer (PHL): re-uses the existing DECT specification EN 300 175-2 Medium Access Control Layer (MAC): extends the existing DECT standard EN 300 175-3 Data Link Control Layer (DLC): extends the existing DECT standard EN 300 175-4 Network Control Layer (NWK): extends the existing DECT standard EN 300 175-5 Security features: extends the existing DECT standard EN 300 175-7 The Interworking Unit (IWU) and the Application Layer Protocol negotiation are covered by the ULE Technical Spec TS 102 939-1.