That is great for research purposes. This platform would use off the shelf PCIe NICs and ram. I think of it as the PostgreSQL of networking gear, cheap and all purpose. It won't have speed or density but it would have robustness and flexibility. Services that currently run on general purpose servers could get targeted towards open network hardware platforms. I don't have any proof, but I don't think there would be shortage of people doing interesting things like making hardware in memory key value stores.
FPGAs would be cost competitive in a system like this. Routing multiple 100MB/s streams of shouldn't be a problem.
> I don't have any proof, but I don't think there would be shortage of people doing interesting things like making hardware in memory key value stores.
what you are describing are also known as CAM tables. for some preliminary introduction check this out : http://www.pagiamtzis.com/cam/camintro/
Ultimately I think such a design would have trouble competing with a network processor (or a switch chip if you're doing something simple).