Project factsheet information

Project Title Coding internet satellite links for better goodput under bandwidth and latency constraints
Full name and acronym University of Auckland

Private Bag 92019, Auckland, New Zealand

Phone +6499235282
Fax +6493737453
Dates covered by this report: 01-01-2018 – 31-12-2018 –
Report submission date 18-01-2019
Country where project was implemented New Zealand
Project leader name Ulrich Matthias Speidel
Project Team Lei Qian
Partner organization Steinwurf ApS, Denmark
Total budget approved US$34,345.05
Project summary

Many Pacific islands rely on expensive narrowband satellite links for international backhaul connectivity. To make matters worse, many such links exhibit extreme TCP queue oscillation, which causes large end user downloads to slow down to a crawl well before the links reach capacity. This problem causes TCP senders to operate with out-of-phase congestion windows that are either much large or much smaller than they ought to be. The latter case leads to link underutilisation after burst packet losses at the link input queue. In a previous project [1], we demonstrated that transparent forward error correction coding with a random linear network code across packets could recoup some of the lost capacity in a real deployment – albeit only for the individual flows we were able to access. In the follow-up project [2], we built a large hardware-based simulator to see whether this solution could be scaled. This project taught us a lot about the need for efficient and well-timed coding in such a bandwidth-constrained environment. The present project aims mainly at a major software upgrade of the coding software to be able to configure the timing of coding redundancy more flexibly, and to be able to avoid the ineffective coding of small packets and flows.