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arXiv · 2611.03457

Expander Routing under Adversarial Deletions via Temporal Aggregation

Bernhard Haeupler·Anton Paramonov
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Abstract

In expander routing, we seek to establish paths in the expander graph between given source-target pairs while minimizing both dilation (maximum path length) and congestion (maximum edge load). We study this problem in a decremental dynamic setting where the underlying graph remains an expander despite ongoing edge deletions, and source-target pairs can be added or removed. Our goal is to maintain paths under these updates while keeping dilation and congestion low and performing low computation per update. We present a randomized algorithm that maintains paths with polylogarithmic dilation and congestion against an adaptive adversary, while incurring only polylogarithmic amortized computation per update, all with high probability. Our approach leverages a recent technique called Temporal Aggregation to maintain a collection of low-congestion, low-dilation random walks resilient to adaptive adversaries.

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Bernhard Haeupler, Anton Paramonov. 2026-11-02. Expander Routing under Adversarial Deletions via Temporal Aggregation. https://arxiv.org/abs/2611.03457

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