Route and Call Quality
The LCR team also has to take route and call quality into account. The quality of route to a destination can vary considerably between suppliers and even from week to week from the same supplier.
Quality is usually measured by the Answer-Seizure Ratio (ASR = call attempts answered / call attempts), Post-Dial Delay (PDD) and the Average Call Duration (ACD). If the average call duration is very low, it is taken to mean that the call quality is so poor that people cannot have a conversation and hang up. This matters to calling card operators because people do not re-purchase card services that give a low ACD. In case of significant discrepancies in ACD values across available routes, the carrier shall prioritize the routes offering higher ACD. A low ASR is taken to mean that callers cannot get through to the other end and hence that the route is congested or is of low-quality. The low ASR is not as bad as low ACD, because it suggests at least a proper answer supervision (i.e. correct signaling), and therefore the handover mechanism can reroute calls via other available routes. An on-line monitoring system of a quality based routing is publicly available for a demo traffic. Post-dial delay is the time from dialing the last digit to the time a caller hears ringing.
Another, more sophisticated way of measuring the call quality is PESQ (Perceptual Evaluation of Speech Quality). Such measurements are rarely used in production switching systems, in particular due to the necessity of voice samples at both ends.
Additionally, the team may take into account the responsiveness of their supplier's technical team: if there is a fault or low quality, does the supplier fix it or just say that it is the best they can do?
Read more about this topic: Least-cost Routing
Famous quotes containing the words route, call and/or quality:
“no arranged terror: no forcing of image, plan,
or thought:
no propaganda, no humbling of reality to precept:
terror pervades but is not arranged, all possibilities
of escape open: no route shut,”
—Archie Randolph Ammons (b. 1926)
“They call, even if I’m pinned behind bars.
They call, they call their green death call.
They want me. They need me.”
—Anne Sexton (1928–1974)
“Upon the whole, necessity is something, that exists in the mind, not in objects; nor is it possible for us ever to form the most distant idea of it, consider’d as a quality in bodies. Either we have no idea of necessity, or necessity is nothing but that determination of thought to pass from cause to effects and effects to causes, according to their experienc’d union.”
—David Hume (1711–1776)