Figure of Merit for Facsimile Transmission Performance - Telephone Network and ISDN Quality of Service Network Management and Traffic Engineering (Study Group 2) 6 pp
The purpose of this Recommendation is to introduce metncs for Figure of Merit (FOM) for end-to-end facsimile transmission performance. The Recommendation is intended for use by Recognized Operating Agencies (ROAs) to exchange network performance data for service improvement purposes. In previous Recommendations E.45 1, E.452, E.453 and E.456, facsimile meîrics such as facsimile call cut-Offs, modem speed reduction and image quality based on scan line errors and test transactions, respectively, were defined. It would be very useful to produce simple metrics for facsimile FOM that combine all three parameters so that performance of networks can be compared easily and corrective action taken to improve performance. End-to-end facsimile performance includes performance impacts both due to the network and the facsimile terminals. However, when a fixed set of test terminals with nominal terminal performances are used, it is possible to treat the terminal performance as a constant factor and compare network performances. The impact of terminal performance on facsimile call cut-Offs, modem speed reduction and image quality are more fully discussed in Recommendations E.451. E.452 and E.453.