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arXiv · 2504.19878

FoldedHexaTorus: An Inter-Chiplet Interconnect Topology for Chiplet-based Systems using Organic and Glass Substrates

Patrick Iff·Maciej Besta·Torsten Hoefler
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Abstract

Chiplet-based systems are rapidly gaining traction in the market. Two packaging options for such systems are the established organic substrates and the emerging glass substrates. These substrates are used to implement the inter-chiplet interconnect (ICI), which is crucial for overall system performance. To guide the development of ICIs, we introduce three design principles for ICI network topologies on organic and glass substrates. Based on our design principles, we propose the novel FoldedHexaTorus network topology. Our evaluation shows that the FoldedHexaTorus achieves significantly higher throughput than state-of-the-art topologies while maintaining low latency.

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Patrick Iff, Maciej Besta, Torsten Hoefler. 2025-04-28. FoldedHexaTorus: An Inter-Chiplet Interconnect Topology for Chiplet-based Systems using Organic and Glass Substrates. https://arxiv.org/abs/2504.19878

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