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Abstract—This paper starts from very fresh analysescomparing brain’s connectivity with those of well-knownnetwork topologies, based on the latest interpretation of Rent’srule. Those analyses have revealed how close the brain comes tothe latest Rent’s rule averages. On the other hand, all the knownnetwork topologies seems to fall short of being strong contendersfor mimicking the brain. That is why this paper performs a detailed Rent-based (top-down) connectivity analysis of manytwo-level hybrid network topologies. This analysis aims to identify those two-level hybrid network topologies which are able to closely mimic brain’s connectivity. The ranges of granularity(as given by the total number of gates and the number of processors) where this mimicking is happening are identified.These results should have implications for the design ofnetworks(-on-chip) and for the burgeoning field of multi/many-core processors (in the short to medium term), as well as for investigations on future nano-architectures (in the long run).Complementary results using a bottom-up approach have also been obtained, and will be mentioned.

Index Terms—Connectivity, interconnect topology, networktopology, communication, nanotechnology, nano-architecture,Rent’s rule, neural network, brain.

“Small devices carry small currents and are thereforeessentially high-impedance (and low-capacitance) devices,both for outputs and inputs, but electrical transmission isunavoidably low impedance (or high capacitance per unitlength).”

“the miniaturization of interconnects,unlike transistors, does not enhance their performance”

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“How should the interconnecttopology look like?”

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978-1-4244-2553-2/08/$20.00 c©2008 IEEE

A. Rent’s Rule

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2008 IEEE/ACM International Symposium on Nanoscale Architectures (NANOARCH 2008) 55

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the brain of humans consumes 20% of the energy, which isvery expensive!

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56 2008 IEEE/ACM International Symposium on Nanoscale Architectures (NANOARCH 2008)

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[ieee 2008 ieee international symposium on nanoscale architectures (nanoarch) - anaheim, ca, usa...

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