ppendix I, "Deployment scenarios for partial timing support networks" Appendix II, "Considerations for handling precision time protocol traffic in networks with par- tial timing support" (because there is no assistance for PTP in the network elements, the engin- eers must very carefully design the network to minimize the sources of time error) Appendix III, "The use of frequency to maintain precise time" Appendix IV, "Noise accumulation model in partially aware networks" G.8271.2 is also a very important recommendation because it applies to those situations where an operator is not able to provide full timing support on their network. Link to recommendation: https://handle.itu.int/11.1002/1000/13768 8.4.1 Node and Clock Performance Recommendations Following on from the end-to-end network topologies, limits, and budgets, the next step is to ad- dress the individual elements and clocks within that network. Once the end-to-end budget is alloc- ated, the performance of the individual network elements needs to be characterized. In ITU-T terms, these node values are known as equipment limits and include several types of timing error for each of the individual clock types (grandmaster clocks, boundary clocks, transparent clocks, and slave clocks). These clock recommendations include parameters such as constant time error, noise generation, noise tolerance, noise transfer, phase error, jitter and wander, and SO on. Please see Chapter 5 for more details on these parameters. The following sections start with the case of network elements carrying frequency with PTP. The recommendations covering the source of frequency (PRC or ePRC) for this case is in the preceding section covering G.811 and G.811.1. Since there is no on-path support with this architecture, there is only a single recommendation (G.8263) covering master and slave packet clocks. Following that section is coverage of the case of network elements carrying time and phase starting from the PRTC source of time (G.8272, G.8272.1). After that is coverage of the PTP 