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No Signal to Rule Them All: A Systematic Analysis of In-Network Congestion Signals

Authors Sarah McClure , Nandita Dukkipati , Sylvia Ratnasamy , Scott Shenker

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Subject Classification

ACM Subject Classification
  • Networks → Network protocol design
  • Networks → Signaling protocols
  • Networks → Transport protocols
  • Networks → Network control algorithms
  • Networks → Network simulations
  • Networks → Network performance modeling
  • Networks → Network performance analysis
Keywords
  • Congestion control
  • in-network telemetry

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Abstract

In this paper, we address the following question: what in-network signals should a network provide to congestion control algorithms? To answer this guiding question, we use prior work to automatically generate congestion control algorithms optimized for a given performance objective and set of in-network congestion signals. We then make observations about the relative value of these congestion signals across a range of performance objectives. Our analysis yields a surprising central finding: for the average case, sophisticated In-Network Telemetry (INT) offers minimal performance benefits over traditional end-to-end (E2E) signals, with performance typically within 3%. We also find no single "best" INT signal, but rather a clear trade-off that manifests in many scenarios: link-based signals often excel at controlling delay, while queue-based signals are better for maximizing throughput. To make these findings concrete, we validate them by examining the extent to which in-network signals improve the performance of the BBR congestion control algorithm.

Cite As Get BibTex

Sarah McClure, Nandita Dukkipati, Sylvia Ratnasamy, and Scott Shenker. No Signal to Rule Them All: A Systematic Analysis of In-Network Congestion Signals. In 1st New Ideas in Networked Systems (NINeS 2026). Open Access Series in Informatics (OASIcs), Volume 139, pp. 12:1-12:30, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/OASIcs.NINeS.2026.12

Author Details

Sarah McClure
  • University of California Berkeley, CA, USA
Nandita Dukkipati
  • Google, Palo Alto, CA, USA
Sylvia Ratnasamy
  • University of California Berkeley, CA, USA
Scott Shenker
  • University of California Berkeley, CA, USA
  • ICSI, Berkeley, CA, USA

Supplementary Materials

References

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