Abstract
With the development of technology, cryptography needs to be improved to remain with the same strength of security, so as for meters for smart grid. The cipher suites used in smart grid meters defined in DLMS/COSEM are not RSA but rather ECDSA. However, users who would like to enroll for an ECDSA certificate will need a pre-shared password with the server. To change that, we use the ECDH method to overcome the limitation from others’ previous research. Also, to authenticate the requests from the meters for the smart grid, we use a temporary certificate mechanism to authenticate the SCEP protocol request, and the mechanism also supports the EST protocol to establish a security communication channel. With ECDH implementation in SCEP and the authentication method, the ECDSA certificate can be compatible with the SCEP protocol and the transmission can be done without a shared password.