Described herein is a method and system for distributing requests and responses across a multi-core system. Each core executes a packet engine that further processes data packets allocated to that core. A flow distributor executing within the multi-core system forwards client requests to a packet engine on a core that is selected based on a value generated when a hash is applied to a tuple comprising a client IP address, a client port, a server IP address and a server port identified in the request. The packet engine maintains the client IP address, selects a first port of the core, and determines whether a hash of a tuple comprising those values identifies the selected core. A modification is then made to the client request so that the client request includes a tuple comprising the client IP address, the server IP address, the first port and the server port.