and CSN elements and will test interoperability at defined reference points within the network for inter-ASN, intra-ASN, and ASN- to-CSN messaging. The RCT, PCT, RPT and IOT/MIOT modules are based on the IEEE 802.16 and the ETSI HiperMAN standards, and exclusively target MAC and PHY capabilities. NCT and IIOT are based on the WiMAX Forum Network specifications and target upper layers as shown in Table 4.4. 4.6.2.3 Certification Labs To ensure independence, consistency, and choice, WiMAX Forum Designated Certification Labs (WFDCLs) have been selected to conduct the certification testing. WFDCLs undergo a rigorous selection process, and their final nomination is sanctioned by the CWG and approved by the WiMAX Next Generation Mobile Communications Ecosystem Table 4.4 WiMAX certification modules Open System Interconnection (OSI) Model WiMAX Forum Specifications Certification Modules Application Layer WiMAX Forum Network Specifications NCT, IIOT Presentation Layer Session Layer Transport Layer Network Layer Data Link Layer - Logical Link Sublayer Data Link Layer - MAC Layer WiMAX Forum System Specifications PCT, IOT, MIOT (based on IEEE 802.16) Physical (PHY) Layer RCT, IOT, MIOT, RPT Source: 2008 WiMAX [17] Forum Board of Directors. Currently, there are four WFDCLs namely AT4 Wireless (Spain and USA), Bureau Veritas ADT (Taiwan), CCS/TTC (Taiwan), China Academy of Telecommunication Research (China) and Telecommunications Technology Association (South Korea). The Forum is looking to open additional labs in Brazil, India and Japan. The testing is performed under the guidance of the WiMAX Forum, following the specifications and test suites set forth by the WiMAX Forum and using the test equipment sanctioned by the Forum. Test equipment is supplied by leading vendors that include Agilent, Anite, AT4, Azimuth, Innowireless, Tektronics, Rohde and Schwarz, and Sanjole. When a product passes the certification testing, the WFDCL formally issues the WiMAX Forum Certified certificate. 4.6.3 How Does Certification Work? The WiMA