network tracking

Network tracking is a comparative measure of the number of packets faithfully transmitted and received to the total number transmitted, expressed as a percentage. Packet loss in the context of QoS does not relate to drops because of network outages or link flaps (because these are a function of a high-availability network design), but instead relates to drops because of network congestion

Delay (or latency) This is the finite amount of time that it takes a packet to reach the receiving endpoint after being transmitted from the sending endpoint. In the case of voice, this equates to the amount of time that it takes for speech to leave the speaker's mouth and be heard by the listener's ear. This time period is termed end-to-end delay and is comprised of two components: fixed network tracking and variable network delay