|
|
||||||
|
|
Quality of Service |
|||||
|
|
||||||
|
Start the applet |
||||||
|
Quality of Service (QoS) refers to the "classification of packets for the purpose of treating certain classes or flows of packets in a particular way compared to other packets" [Policy Terms]. Ideally, it means making the data delivery service of the otherwise unpredictable "best effort" Internet Protocol (IP) network, predictable. To enable QoS requires the use of protocols such as [RSVP] which provides the signaling required for integrated services and [DiffServ] for differentiated services. RSVP affects the allocation of network resources on a per-flow basis according to the quantitative requirements of applications, whereas DiffServ provides markings within the IP packet headers to allow prioritization of traffic aggregates (i.e. "classes" of multiple flows). |
The QoS characteristics can be defined by the following parameters. |
|||||
|
The availability means that a user has reliable network connectivity and this is the most basic parameter of telecommunication. The delay includes two factors of single-direction transmission delay and round trip time (RTT). These are important factors for real-time applications such as VoIP (Voice over IP). The jitter is variation in delay and is important factor for real-time applications. The packet loss probability is the rate of missing packets and is important for mission critical applications. The throughput is the data rate that the system can transfer, and this factor is important for streaming applications.
|
||||||
|
|
4 Parameters can be adjusted: |
|||||
