Consistency of Service (COS): What is quality of service? If these graphs represent typical download rates over time from two different broadband Internet providers, both providing an average of 3 Mbps, which service provider should get the higher quality of service rating?
The first provider (A) should win hands down and that is the basis for the MyConnection Server Quality of Service measurement. Being able to provide a consistent download capacity is what quality of service is all about. The MyConnection Server Quality of Service measurement is a very simple calculation:
——————— = Quality of Service
which is just the minimum speed observed during a large download divided by the maximum speed observed, resulting in a percentage number from 0 (worst) to 100 (best). The higher the percentage, the better the quality of service. Variation in the download rate is undesirable and is penalized (resulting is a lower percentage number).
In the example graphs above, the COS for provider A is 100% (5/5), whereas the COS for provider B is 20% (1/5).
Please note that the MyConnection Server COS percentage is independent of line speed. The above graphs could be Kbps instead of Mbps and the providers would still obtain the same COS numbers. This is by design. The MyConnection Server COS metric measures line quality, not line speed.
T1 Line: For example, on a virtually unused T1 line (1.544 Mbps), MyConnection Server repeatedly reported a download speed of 1.46 Mbps and an upload speed of 1.44 Mbps, and as you expect, a COS in the upper 90's.
DSL: On a DSL connection, you can expect to see a consistently high COS number (when you are the only person using the DSL connection). If you don't, contact your DSL provider to file a problem report.
Cable Modem: On a high quality cable modem network, you can expect a COS in the 90's or 80's. However, because you have the potential for sharing your connection with everyone in your neighborhood, some low quality networks will see lower numbers, sometimes even below 10!
Voice over IP (VoIP), Multimedia: For today's popular multimedia, IP telephony and similar bandwidth-hungry applications, consistent download capacity and a high COS are imperative. Fluctuating bandwidth frequently results in jitter and broken connections.