In Hyperledger Fabric, the Gateway service manages the transaction submission process on behalf of the client application. This service simplifies the interaction with the network by abstracting the details of transaction construction, endorsement, and submission. The Gateway service assembles the necessary endorsements according to the relevant chaincode endorsement policies and submits the transaction to the ordering service.
This role of the Gateway enhances the usability and efficiency of transaction processing, reducing the complexity for client applications by handling these critical steps internally.