Achraf_JSC_Draft の履歴(No.4)

Title: Low latency Hybrid Photonic Network On Chip Routing and router architecture†

1- Abstract:

Despite the increase of the performance by the photonic integration in the NoC interconnect, Hybrid NoC still suffers from a latency overhead mainly caused by the path reservation.
In order to solve this issue, we propose a new path setting mechanism. The proposed scheme will separate the routing computation and the arbitration stage, which are performed conventionally in the electronic control plane.
The electronic plane will just perform the routing computation by finding the appropriate route following LA-XY algorithm. The routing computation result will be send to the corresponding photonic switch (in the optical transmission layer).
Another cause of the latency in the hybrid NoC, is the acknowledgements and the path teardown signal, which are performed conventionally in the electronic plane. In the proposed path setup scheme all ACKs and the path teardown signals will be generated and transmitted in optical layer.
In order to handle the arbitration and the generation of the ACKs and the teardown, an optimized version of PHENIC photonic switch is proposed.

2- Introduction:

Semiconductor evolution
2D and 3D limitations.
Evolution of the nanophotonics silicon based technology and how photonic components based on silicon can be integrated with electronic components in the same wafer. Example of such components and their characteristic will be given.
Existing Photonic NoC architecture. • Fully optical NoC: Advantages and disadvantages.
- Very short latency
- Minimal bandwidth
- Typical computer system communication requires small and large messages. The E/O and O/E for small message are characterized by a power overhead.

• Hybrid photonic NoC : Advantages and disadvantages.

High bandwidth through WDM
Electronic network still available for small control messages
Latency Overhead for path setting
- All resources (i.e, input port, output port and MRs for every hop used in the communication )still reserved until the end of the communication.
- small message will have to wait until the path release.

The proposed photonic NoC will be hybrid based. With the capability of enhance and get rid of the limitations of the hybrid architecture.

3- Related work.

4- Photonic Hybrid NoC Path setting .

4.1 A congestion aware Path setup mechanism.

5- Evaluation

6- Conclusion