The method provides a multi system trust chain between a client system and a remote system in a secure connection, wherein an intermediary system associated with the network flow path serves as a signing entity to establish an end to end transitive trust. The intermediate system is a corroborative entity in the operations technology (OT) realm of the client system. The remote system serves as the host for a plurality of services in the information technology (IT) realm. A two way handshake during the initial secure exchange protocol between a local client application and a remote service is extended to a three way handshake that includes a nonce issued by the remote service on the remote system and a digital signature for the nonce issued by a signature service on an associated intermediate system. The nonce signature is verified authoritatively at the remote system based on the signing certificate of the intermediate system for explicit proof of association.