A system includes an intelligent electronic device (IED) configured to perform operations that include receiving a first user input and deriving a first connectivity association key (CAK) based on the first user input. The system also includes a gateway configured to perform operations that include receiving a second user input, deriving a second CAK based on the second user input, identifying the first CAK of the IED, establishing an adoption link with the IED based on a match between the first CAK and the second CAK, generating a third CAK, and distributing a copy of the third CAK to the IED via the adoption link to establish a MKA connectivity association with the IED.