ed to distribute time from a grandmaster clock to the end devices over 16 network hops (TC nodes). The time error between the time recovered by the end device and the standard time source (UTC) should be less than +1 us. This applies even for network loads up to 80% wire-speed (line rate) on each link. 7.5.1 SMPTE ST-2059-2 and AES67 Media Profiles The SMPTE profile is part of the SMPTE ST-2059 standard and was created specifically to syn- chronize video equipment in a professional broadcast environment. This profile helps keep multiple video sources in synchronization across numerous pieces of equipment by providing time and fre- quency synchronization to all devices. It was designed with the following goals: For a slave to achieve synchronization within 5 seconds of being connected to an operational PTP network Upon phase alignment, to maintain time accuracy between any two slave devices with respect to the master reference within 1 us To transport synchronization metadata (SM) required for synchronization and time labeling of audio/video signals That last requirement is supported by the master port in a grandmaster clock sending a Management message with an SM TLV appended once per second (something that, for instance, the telecom pro- files will not support). Regarding frequency accuracy, the PTP grandmaster clock shall also main- tain a frequency with a maximum deviation within 5 parts per million (ppm) from the SI second. The AES67 Media Profile is part of the AES67 standard and supports professional-quality audio ap- plications for high-performance streaming in media networks. The requirement for accuracy and frequency stability is not quite as strict as ST-2059-2 (for example, frequency to within 10 ppm rather than 5 ppm for the video standard). Although sourced from different organizations, most of the major parameters in the two profiles, AES67 and SMPTE ST2059-2, have minimal differences. The selected transport type for both is IPv4 (multicast) and based on Internet Group Management Protocol (IGMP) ver