Worked on the grpc/grpc-java repository to deliver per-target credentials configuration for gRPC xDS, enabling granular authentication control in multi-target service mesh environments. Updated the GrpcXdsTransportFactory and related transport code to accept and pass CallCredentials during channel creation, allowing each xDS target to receive its own credentials. This approach enhances security by reducing the risk of credential leakage and supports more precise policy enforcement. The work was implemented in Java, leveraging expertise in authentication, network programming, and gRPC protocols. These changes also established a foundation for future improvements in credential scoping and auditing within the transport layer.