# 2SYN: Congestion-Aware Multihoming

## TL;DR

2SYN is a novel congestion-aware multihoming algorithm that dynamically selects optimal paths for new connections, improving network performance and adaptability in diverse real-world scenarios.

## Contribution

It introduces the first congestion-aware multihoming method applicable to any destination, with practical implementation and real-world performance validation.

## Key findings

- Outperforms alternative approaches in real-world LTE and wired link tests.
- Dynamically adapts to connection quality changes.
- Easily implementable in Linux environments.

## Abstract

When sending flows to arbitrary destinations, current multihoming routers adopt simple congestion-oblivious mechanisms. Therefore, they cannot avoid congested paths. In this paper, we introduce 2SYN, the first congestion-aware multihoming algorithm that works for any destination. We explain how it dynamically selects a preferred path for new connections, even given previously-unseen destinations. We further demonstrate that it can be easily implemented in Linux. Finally, in a real-world experiment with either LTE or a wired link, we show how 2SYN dynamically adapts to the quality of the connection and outperforms alternative approaches. Thus, 2SYN helps companies better manage their networks by leveraging their multihoming capabilities.