Quality of Service

This past Friday we started a new topic with Professor Josep Solé, which introduced us in the Quality of Service concept.

QoS is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. The need to develop QoS are the new requirements on the Internet, such as required bit rate, bounds on delay and jitter, packet dropping probability, sufficient bandwidth, bit error rate…

These requirements vary from application to application, i.e. Internet telephony requires low end-to-end latency in order to do the conversation understandable, or video streaming can tolerate moderate end-to-end delay but no errors on data.

We treated an example to get a better approaching to the QoS: the Digitalization of the Voice.

There are many things than can affect the QoS, the most important we talked were the Nyquist criteria, in order to receive properly the modulated signal, and the number of bits per sample, to minimize the quantization error.