Contracts: A unified lens on congestion control robustness, fairness, congestion, and generality
Fuente:
arXiv
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908395808751616 |
|---|---|
| author | Agarwal, Anup Arun, Venkat Seshan, Srinivasan |
| author_facet | Agarwal, Anup Arun, Venkat Seshan, Srinivasan |
| contents | Congestion control algorithms (CCAs) operate in partially observable environments, lacking direct visibility into link capacities, or competing flows. To ensure fair sharing of network resources, CCAs communicate their fair share through observable signals. For instance, Reno's fair share is encoded as $\propto 1/\sqrt{\texttt{loss rate}}$. We call such communication mechanisms \emph{contracts}. We show that the design choice of contracts fixes key steady-state performance metrics, including robustness to errors in congestion signals, fairness, amount of congestion (e.g., delay, loss), and generality (e.g., range of supported link rates). This results in fundamental tradeoffs between these metrics. Using properties of contracts we also identify design pitfalls that lead to starvation (extreme unfairness). We argue that CCA design and analysis should start with contracts to conscientiously pick tradeoffs and avoid pitfalls. We empirically validate our findings and discuss their implications on CCA design and network measurement. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2504_18786 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Contracts: A unified lens on congestion control robustness, fairness, congestion, and generality Agarwal, Anup Arun, Venkat Seshan, Srinivasan Networking and Internet Architecture Congestion control algorithms (CCAs) operate in partially observable environments, lacking direct visibility into link capacities, or competing flows. To ensure fair sharing of network resources, CCAs communicate their fair share through observable signals. For instance, Reno's fair share is encoded as $\propto 1/\sqrt{\texttt{loss rate}}$. We call such communication mechanisms \emph{contracts}. We show that the design choice of contracts fixes key steady-state performance metrics, including robustness to errors in congestion signals, fairness, amount of congestion (e.g., delay, loss), and generality (e.g., range of supported link rates). This results in fundamental tradeoffs between these metrics. Using properties of contracts we also identify design pitfalls that lead to starvation (extreme unfairness). We argue that CCA design and analysis should start with contracts to conscientiously pick tradeoffs and avoid pitfalls. We empirically validate our findings and discuss their implications on CCA design and network measurement. |
| title | Contracts: A unified lens on congestion control robustness, fairness, congestion, and generality |
| topic | Networking and Internet Architecture |
| url | https://arxiv.org/abs/2504.18786 |