Appendix K. Constant Quality Monitoring - technical details

Table of Contents

The FireBrick provides constant quality monitoring. The main purpose of this is to provide a graphical representation of the performance of an interface or traffic shaper - typically used for broadband lines on L2TP .

100 second interval statistics available graphically as svg or png and in text as csv covering at least the last 25 hours (one day)
Loss latency stats where available (e.g. LCP echos on L2TP broadband lines) including minimum, average, and maximum latency for the 100 second sample, and percentage packet loss.
Throughput stats where available (e.g. interfaces, shapers , L2TP broadband lines ) including average tx and rx rate for 100 second sample

Graphs can be loss/latency or throughput of both. A ping only system would only have loss/latency. An L2TP broadband line has both. An interface or shaper normally has only throughput data.

K.1. Broadband back-haul providers

When using the FB2500 as an LNS the CQM graphs are invaluable for diagnosing line faults. They are useful to the ISP but also useful to the back-haul provider which is often a separate company (e.g. BT or Be). We recommend that you consider providing access to graphs for live circuits and archived data to your back-haul provider when discussing faults with them. FireBrick are working with several ISPs to ensure back-haul providers are aware of the CQM graphs and how to use them to assist in diagnosis.


J.9. Advanced commands		K.2. Access to graphs and csvs