Radio Frequency Identification (RFID) system is a low-cost contactless automatic identification technology; and barcode as a traditional technology is now broadly replaced by RFID systems to make objects more manageable in supply chains and other enterprises. This technology is operational in open wireless communication spaces whereby its transmission signals can be easily accessed resulting in security problems. Consequently, it becomes an absolute necessity to develop efficient security protocols to protect the data against various attacks. This paper outlines a critical evaluation of the RFID systems, the security and privacy issues in the RFID security protocols, the EPCglobal Class-1 Generation-2 standard as it is an international standard, its lower cost of implementation, and high speed data transmission and operation.