Systems and methods for supporting SMA level abstractions at router ports for enablement of data traffic in a high performance computing environment. In accordance with an embodiment, a subnet manager in a local subnet is responsible for enabling data traffic between subnets in a high performance computing environment. The SM can configure and set a data attribute at a switch port configured as a router port such that incoming data packets can be checked against the attribute to determine whether the data packet's destination is allowed or disallowed to receive inter-subnet data traffic.