Authors:
E. A. Jammeh
;
M. Fleury
and
M. Ghanbari
Affiliation:
University of Essex, United Kingdom
Keyword(s):
Congestion control, video streaming, fuzzy logic.
Related
Ontology
Subjects/Areas/Topics:
Multimedia
;
Multimedia and Communications
;
Multimedia Streaming (Ipv4 / Ipv6)
;
Telecommunications
Abstract:
Existing congestion controllers have been designed with TCP traffic in mind. Changing traffic patterns on the Internet imply that on some tight links all UDP video streams will occur. Three different congestion controllers (RAP, TFRC, and fuzzy-logic based), already successful in avoiding instability in current TCP-dominated internets, were tested across a tight link in which video traffic dominated. Congestion control is either achieved by modulating the sending rate in response to feedback of packet loss rates and/or round-trip delays (RAP/TFRC) or a congestion level based on packet dispersion across a network path (fuzzy controller). The controllers were found to differ in the smoothness of resulting video clip streams, with the fuzzy and TFRC controllers, in that order, producing the smoothest received video. Tests also demonstrated that, when controlled flows of different types compete across a tight link, it is possible for the sending rate of TFRC to exceed the available bandw
idth, resulting in excess packet loss and implying quite poor video quality at the receiver. The results show that fuzzy-logic control is more flexible when video streams dominate.
(More)