Many Pacific Island nations rely on expensive satellite Internet links with low bandwidth and high latency. Small populations, low per-capita GDP, huge distances and a mostly very deep ocean make submarine fibre cables prohibitive for many. To add insult to injury, many ISPs in the islands struggle to utilise the full capacity of their satellite links. The culprit is TCP queue oscillation, an effect discovered decades ago - and widely considered solved through the evolution of TCP/IP stacks. However, we show that it does still occur across satellite links where a large number of TCP senders share the same bandwidth into the island. We also demonstrate that coding packets allows TCP flows to recoup some of the capacity lost to queue oscillation, and report about ongoing work to simulate whole-of-island network coding of traffic.

Biography

Ulrich Speidel is a senior lecturer in Computer Science at the University of Auckland, New Zealand. He trained as a physicist in Germany and New Zealand, morphed into a CS person as part of his PhD, and served as an associate professor at the University of Tokyo in 2010. His research covers aspects of information theory, signal processing, network measurement, Internet protocols, applications and security.

Many Pacific Island nations rely on expensive satellite Internet links with low bandwidth and high latency. Small populations, low per-capita GDP, huge distances and a mostly very deep ocean make submarine fibre cables prohibitive for many. To add insult to injury, many ISPs in the islands struggle to utilise the full capacity of their satellite links. The culprit is TCP queue oscillation, an effect discovered decades ago - and widely considered solved through the evolution of TCP/IP stacks. However, we show that it does still occur across satellite links where a large number of TCP senders share the same bandwidth into the island. We also demonstrate that coding packets allows TCP flows to recoup some of the capacity lost to queue oscillation, and report about ongoing work to simulate whole-of-island network coding of traffic.

Biography

Ulrich Speidel is a senior lecturer in Computer Science at the University of Auckland, New Zealand. He trained as a physicist in Germany and New Zealand, morphed into a CS person as part of his PhD, and served as an associate professor at the University of Tokyo in 2010. His research covers aspects of information theory, signal processing, network measurement, Internet protocols, applications and security.