Some people think that EMV certification process consists of host certification and terminal certification only. In reality, EMV processing functionality also includes another important component: handling of EMV parameters and EMV application keys.
A lot of developers understand how important it is only at later phases of EMV functionality implementation. Handling of EMV parameters and EMV keys rotation is particularly important if you are dealing with several acquirers. EMV parameters and keys are needed to ensure proper exchange of information between the chip and the EMV kernel of the payment terminal.
A terminal, usually, has a configuration file stored in it. The file includes the list of AIDs, supported by this terminal, respective application parameters and keys for them. EMV kernel uses this file for its operation.
In contrast to EMV parameters, EMV keys need to be changed at regular time intervals. EMV keys rotation is sometimes performed through an API, provided by the processor. You need some efforts to implement EMV keys rotation logic, so it’s better to allocate some time for its development right from the start.
Rotation of EMV keys can be either embedded in the terminal management system (TMS), or it can be a part of payment gateway functionality.
More information on EMV parameters and EMV keys rotation is available in the respective article on Paylosophy.com.