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Tiers1 ≅ EMV Level1: level covering all platform related services. It includes card coupling (CT and CL)
Tiers2 ≅ EMV Level2: level covering card processing services. It covers EMVCo L2 CT , EMVCo L2 CL, and payment networks' CL specifications
Tiers3 ≅ EMV Level3: level covering payment services. It covers all applications or libraries providing services to sales systems, or using services from TMS, or acquirer/processing systems
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