Reliable communications over lossy wireless channels by means of the combination of UDP and Random Linear Coding

Abstract

It goes without saying that TCP is the de-facto transport protocol to ensure reliable communications (for instance, in file transfers). On the other hand, and despite the growing relevance of wireless networks, the behavior of TCP over such technologies is well-known to present clear limitations. Several approaches have been made so as to overcome these problems. In this work we propose a different approach to ensure reliable transmissions over wireless links, based on an Random Linear Coding (RLC) scheme, operating together with UDP. We provide a model of the expected performance of the new scheme. Furthermore, based on an extensive simulation campaign over the ns-3 simulation framework, we assess the validity of this model and we compare its performance with that exhibited by the legacy TCP. The results show that, in particular for lossy links, the proposed scheme clearly outperforms TCP.

Performance of Random Linear Coding Over Multiple Error-Prone Wireless Links

“…We used IEEE 802.11 b links (working at 11 Mbps) and we disabled the MAC retransmission scheme, since it has been shown [5] that it does not provide any benefit to the RLC protocol performance.…”

“…The authors in [5] studied the most appropriate values for the block size parameter, k. Based on this analysis, we will fix the block size to k = 32 packets. Furthermore, and for the sake of simplicity, we will mostly work with GF (2).…”

Providing Reliable Services over Wireless Networks Using a Low Overhead Random Linear Coding Scheme

“…In previous works [8,9] we have showed the trade-off between the different RLC operational parameters. Intraflow network coding schemes have two main issues: (1) overhead due to the transmission of the random coefficients used by the protocol to combine the different packets; (2) the computational cost of the coding/decoding tasks.…”

Caracterización experimental del comportamiento de Network Coding para comunicaciones multicast

“…El esquema RLNC fue originalmente presentado en [8] y en este trabajo se hace uso de un esquema similar al utilizado en [13]. El nodo origen divide la información a transmitir en generaciones.…”

“…Sin embargo, es importante tener en cuenta asimismo la sobrecarga Garrido, Agüero, 2017. Figura 2: Redundancia que se debería utilizar bajo el esquema RLNC para obtener una probabilidad de 99,99 % de éxito en comparativa con un esquema simplificado de NORM generada por el vector de coeficientes que, según se analizó en [13], no debería superar un tamaño de k = 255 para un escenario en el que la Maximum Transfer Unit (MTU) sea de 1500 bytes, puesto que este vector tendría un tamaño de k·q 8 bytes. En la Figura 2 se comparan el esquema implementado RLNC con una versión simplificada de NORM, tal y como se describe en la Sección B,(Eq.…”