Analytical model and comparative evaluation of application layer loss in the context of media encapsulation in wireless RTC

Abstract

Internet firewalls are typically configured to allow web friendly traffic transported by means of the Transmission Control Protocol (TCP) and, simultaneously as security measure, reject any other type of transport. This is a problem for real time communications that heavily rely on transport types like User Datagram Protocol or those associated to the Internet Security Protocol. A mechanism to overcome this limitation is through stream tunneling where media frames that would be typically rejected by firewalls are encapsulated on top of TCP transport. In this paper, a novel mathematical model that links application layer packet loss to bursty network packet loss in the context of fading channels characteristic of wireless communications is presented for both, datagram and stream encapsulation. This model is compared with experimental scenarios of tunneling applied to state of the art speech codecs such that quality scores are obtained and correlated against theoretical results.