# CASPR: Judiciously Using the Cloud for Wide-Area Packet Recovery

## TL;DR

CASPR introduces a cloud-assisted packet recovery system that uses coded packets sent via reliable cloud paths to quickly recover lost packets, improving latency and reliability for Internet applications.

## Contribution

This paper presents CASPR, a novel system that leverages cloud paths for efficient packet recovery, combining coding and cloud infrastructure for improved Internet performance.

## Key findings

- CASPR achieves faster packet recovery times.
- It reduces packet loss impact on latency-sensitive applications.
- The system is cost-effective and scalable.

## Abstract

We revisit a classic networking problem -- how to recover from lost packets in the best-effort Internet. We propose CASPR, a system that judiciously leverages the cloud to recover from lost or delayed packets. CASPR supplements and protects best-effort connections by sending a small number of coded packets along the highly reliable but expensive cloud paths. When receivers detect packet loss, they recover packets with the help of the nearby data center, not the sender, thus providing quick and reliable packet recovery for latency-sensitive applications. Using a prototype implementation and its deployment on the public cloud and the PlanetLab testbed, we quantify the benefits of CASPR in providing fast, cost effective packet recovery. Using controlled experiments, we also explore how these benefits translate into improvements up and down the network stack.