I/O Acceleration Technology is another item that Intel finally is going to add to its server platforms. While this is a rather general term, it stands for TCP offloading and 'optimized data movement' throughout the platform - whatever this means. According to the slide above this could enable the network controller to write data directly into the main memory.
Intel refers to 'best price performance solution to layer 4/5 acceleration' which refers to the OSI model, in which layer 4 takes care of data transport (by means of TCP - the Transmission Control Protocol) and 5 accommodates the session or protocol such as http or ftp.
Network interface cards that include a hardware TCP offload engine are essential for servers that have to handle both a high CPU load and high network traffic. The TCP activity requires a lot of performance, especially with deployment of 10 Gigabit Ethernet hardware. Intel may have found a nice and rather affordable solution to share the workload between a more intelligent network chip and the multi-core CPUs that will be available.