I have two applications A1 and A2, both creating there own enclave E1 and E2. A third application A3 is connected to A1 and A2. Is it possible for A3 to determine if the two enclaves E1 and E2 are actually running on the same system?
The Signing Identity provided by an authority, which signs the enclave prior to distribution. This value is called MRSIGNER and will be the same for all enclaves signed with the same authority. So in the same development firm all enclaves should have same MRSIGNER value, if they are signed with same Signing Identity.
This MRSIGNER values from two different enclaves in a development environment can be used to check whether two enclaves belongs to the same environment.