Automatic protection switching line card redundancy within an intermediate network node

An apparatus and technique configures an intermediate network node, such as an aggregation router, to implement automatic protection switching (APS) redundancy among its line cards in the event of a failure to one of those cards. The APS line card redundancy provides redundancy among a pair of line cards connected to a performance routing engine of the router. Internal APS data paths are implemented in the router through the provision of an alias logic circuit that selects packet data from one of an adjacent pair of line cards and sends identical copies of data to that adjacent pair of line cards.