1. An off-load engine for processing a data packet conveyed between a target device and a network over a transport connection, the data packet including a payload and a header, the engine comprising: a payload buffer, for holding data that is exchanged between the off-load engine, the network, and the target device for inclusion in the payload; a packet processor, for processing context information with respect to the transport connection; a context buffer, for holding the context information that is processed by the packet processor; a memory access multiplexer, which is coupled to convey the data in the payload buffer and the context information in the context buffer to and from a single memory that stores both the data and the context information; and an arbiter, which is adapted to control the multiplexer by arbitrating among payload requests to convey the data between the payload buffer and the single memory and context requests to convey the context information between the context buffer and the single memory.