On the Trade-off Between Spectrum Efficiency with Dedicated Access and Short End-to-End Transmission Delays with Random Access in DVB-RCS2

TL;DR

This paper compares random and dedicated access methods in DVB-RCS2, showing that random access significantly reduces initial transmission delays for TCP flows but is less bandwidth-efficient and less reliable under overload.

Contribution

It provides a performance analysis of TCP over DVB-RCS2's access methods, highlighting the delay benefits of random access and discussing trade-offs with dedicated access.

Findings

Random access reduces first ten TCP datagram delay by 500 ms.

Dedicated access is more bandwidth-efficient and reliable under overload.

Random access is suitable for low-latency Internet traffic.

Abstract

This paper analyses the performance of TCP over random and dedicated access methods in the context of DVB-RCS2. Random access methods introduce a lower connection delay compared to dedicated methods. We investigate the poten- tial to improve the performance of short flows in regards to transmission delay, over random access methods for DVB- RCS2 that is currently under development. Our simulation experiments show that the transmission of the first ten IP datagrams of each TCP flow can be 500 ms faster with ran- dom access than with dedicated access making the former of interest to carry Internet traffic. Such methods, however, are less efficient in regards to bandwidth usage than dedicated access mecanisms and less reliable in overloaded network conditions. Two aspects of channel usage optimization can be distinguished: reducing the duration of ressource utiliza- tion with random access methods, or increasing the spec- trum efficiency with dedicated access methods. This article argues that service providers may let low-cost users exploit the DVB-RCS2 to browse the web by introducing different services, which choice is based on the channel access method.