Abstract: In certain embodiments, a method includes receiving a message at a first network interface of a first node. The first network interface communicates with a first network while a second network interface communicates with a second network. The method includes determining a set of expected tokens and an expected order of tokens. A plurality of tokens are accessed that were generated for the message, each of the plurality of tokens associated with a policy service of a plurality of policy services. The method includes generating a plurality of decrypted tokens from the plurality of tokens using a first parameter associated with the plurality of policy services and validating the decrypted tokens by comparing the decrypted tokens to the set of expected tokens. In response to validating the decrypted tokens and determining that the decrypted tokens are in the expected order, an approval is generated.