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arXiv · 2605.19169

Modeling the Impact of Fiber Latency on Compute-Communication Overlap in Geo-Distributed Multi-Datacenter AI Training

Ioannis Papavasileiou·Sairam Prabhakar·Indu Kant Deo·Sergejs Makovejs
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Abstract

We use discrete-event simulation to quantify the impact of fiber latency on the efficacy of geo-distributed AI model training with data parallelism. We conclude that the optimum distances between two AI clusters is 10-100km, over which hollow-core fiber enables 25% higher compute-communication overlap.

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Ioannis Papavasileiou, Sairam Prabhakar, Indu Kant Deo, Sergejs Makovejs. 2026-05-18. Modeling the Impact of Fiber Latency on Compute-Communication Overlap in Geo-Distributed Multi-Datacenter AI Training. https://arxiv.org/abs/2605.19169

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