Taking Saratoga from Space-Based Ground Sensors to Ground-Based Space Sensors

TL;DR

This paper discusses the adaptation of the Saratoga transfer protocol, originally used for satellite Earth observation data, to high-throughput data transfer in ground-based radio telescope networks, enabling efficient handling of large sensor data.

Contribution

The paper presents a new implementation of the Saratoga protocol tailored for ground-based sensor networks, demonstrating its potential for high-rate data transfer in VLBI applications.

Findings

Effective data transfer over private networks for VLBI sensors

High throughput and link utilization achieved

Lessons learned in protocol adaptation for sensor networks

Abstract

The Saratoga transfer protocol was developed by Surrey Satellite Technology Ltd (SSTL) for its Disaster Monitoring Constellation (DMC) satellites. In over seven years of operation, Saratoga has provided efficient delivery of remote-sensing Earth observation imagery, across private wireless links, from these seven low-orbit satellites to ground stations, using the Internet Protocol (IP). Saratoga is designed to cope with high bandwidth-delay products, constrained acknowledgement channels, and high loss while streaming or delivering extremely large files. An implementation of this protocol has now been developed at the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) for wider use and testing. This is intended to prototype delivery of data across dedicated astronomy radio telescope networks on the ground, where networked sensors in Very Long Baseline Interferometer (VLBI) instruments generate large amounts of data for processing and can send that data across private IP- and Ethernet-based links at very high rates. We describe this new Saratoga implementation, its features and focus on high throughput and link utilization, and lessons learned in developing this protocol for sensor-network applications.