Multimedia applications have gained in recent years an increasing demand from Internet users as they offer new opportunities and diverse services. These applications, however, are subject to restrictions which mainly have to do with its nature and are characterized by high requirements of the transmission rates (bandwidth-consuming applications) and the sensitivity to packet delays (delay-sensitive applications). On the other hand, allegedly these applications are less sensitive to packet losses (packet-loss tolerant applications). The issue, however, with multimedia applications, except for the scope of the services which offer, is the Quality of Services (QoS) that is offered to the end user. The Quality of Services (QoS) is directly linked to the above characteristics of multimedia applications. Это и многое другое вы найдете в книге Real Time Transport Protocols Over Best-Effort Networks (Georgios Kioumourtzis)