**7. Current situation—South Korea**

Currently, 5G is facing many challenges to be implemented; the following is the case of South Korean mobile carrier. On the 20th of March 2019, South Korean mobile carrier (SK Telecom) announced using quantum cryptograph technology for the security of 5G network. SK applied quantum number generator (QRNG) technology of ID QUANTIQUE (IDQ ) for 5G subscribers to prevent hacking and eaves dropping. SK invested \$65 million into IDQ and plans to expand the use QNRG. Furthermore, SK wants to apply quantum key distribution (QKD) technology in April/2019 [14, 25].
