domain of interpretation (IPsec) (DOI)
In the IPsec protocol, the ISAKMP/ IKE defines the payload format, the switching types and the conventions for the security-relevant information, such as the security policy or the encryption algorithms.
Since there are diverse security protocols and many parameters for communicating the security agreements( SA), one uses the Domain of Interpretation( DOI) as a simplified method for defining the various parameters.
The Domain of Interpretation contains the information about the security protocols, the algorithms and the procedures for the key management and thus important parameters for an IPSec communication.