TABLE OF CONTENTS In order to have a comprehensive overview of the tasks carried out by NIs in NoC architectures, this section presents a classification of the services offered by NIs in categories that have different design challenges [27].
Implementation or not of a service and careful customization of chosen ones depends on the application needs, on the core and NoC protocol features, and is a platform-instance-dependent decision. Services span from session and transport-level services decoupling computation from communication, up to lower-level ones such as packetization and clock-domain crossing.
These are the basic core wrapping services. Their role is to adapt the communication protocol of the component to the communication protocol of the network. Of course, the challenge here is to minimize performance loss from a latency viewpoint.
This task is extremely critical in the context of highly integrated multiprocessor SoCs. In fact, beyond implementing a high-performance physical connection between the NI and the corresponding core, the layering concept is traditionally applied [11, 28]. Layering naturally decouples systemprocessing elements from the system they reside in, and therefore enables design teams to partition a design effort into numerous activities that can proceed concurrently since they are minimally dependent. This can dramatically accelerate final product delivery schedules. Layering also naturally enables core reuse in different systems. Since an individual core's interface is independent of (decoupled from) the system, with the right core interface design, the core can remain unchanged as it is reused in subsequent system...
