Translating low level statistics to an Application Performance rating
Translating low level statistics to an Application Performance rating
The CNA assessment of application performance is based on application models, which convert the raw delay, jitter, and loss measurements into an application performance rating that ranges from 0 to 5. This rating is normalized across applications. Application models are tailored to different applications, including VoIP, and take into account the specific characteristics and requirements of the various applications.
CNA Application Models follow a
Figure 75: Converting raw statistics into an application performance rating
From the bottom, the five steps include:
●The measurement of
The computation of transport delay from the raw scores; this takes into account the distinct characteristics of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP), and thus assesses the impact on applications in general, not taking specific application sensitivities into consideration.
●The computation of application delay, specifically the transaction between the two end points.
●The determination of an application performance rating, using a ranking from one to five stars, similar to movie ratings.
●Finally, the time periods where the voice quality is determined to be unacceptable are logged as “bad minutes” for that path. Adding up the bad minutes allows CNA to compute the effect of network problems on application availability
