luencing the performance of a GNSS-based PRTC Sources of time error in GNSS time distribution Mitigation of time error in a GNSS-based PRTC Operational schemes for mitigation of time error in GNSS time distribution, which covers multi-constellation and multi-band receivers, augmentation systems, and techniques like differ- ential GNSS and post-processing Appendix I, "Cable delay effects and correction in a GNSS receiver" Appendix II, "Ionospheric delay, its effect on GNSS receivers, and mitigation of these effects" Appendix V, "The effect of multiple reflections within the antenna cable" Appendix VI, "Satellite common-view" (whereby accurate time comparisons are made possible by the observation of the same satellites at the same time in different locations) Appendix VII, "The effect of multipath within the receiver signal processing" This report is quite easy to read and full of interesting information. Link to technical report: http://handle.itu.int/11.1002/pub/815052de-en Series G Supplement 68-Synchronization OAM Requirements ITU-T Supplement 68-Synchronization OAM Requirements is a supplement that gives an over- view of OAM for a deployed timing solution. From the scope of the recommendation: This Supplement provides an overview of Synchronization operations, administration and maintenance (OAM) and includes fault management, performance monitoring, alarms and events. This document includes the following main topics: Fault management Performance monitoring Alarms and events This supplement covers three use cases: Frequency synchronization over the physical layer Frequency synchronization via packet-based transport Time synchronization Link to supplement: https://handle.itu.int/11.1002/1000/14232 8.5 Possible Future Changes in Recommendations The last few years have seen some amazing developments in the standardization process for syn- chronization. This is being driven mostly by the innovation coming from 5G and the mobile tele- communications industry. Predicting in which direction the standards are likely t