Netgear M4250-26G4XF-PoE User Manual - Page 17

AV Line of Fully Managed Switches M4250 Series Note: Another PTP feature that the switch supports, PTP residency time stamping, is incompatible with 802.1AS on the same switch. For more information, see About PTP residency time stamping on page 17. If you must support both AVB and PTP residency time stamping in your network, we recommend that you use two separate switches. About PTP residency time stamping Precision Time Protocol (PTP, IEEE 1588) is a protocol that enables precise synchronization of clocks with a sub-microsecond accuracy across a packet-based network. PTP lets network devices of different precision and resolution synchronize to a grandmaster clock through an exchange of packets across the network. The switch supports a PTP end-to-end transparent clock that is used in the PTP residency time stamping feature, which, by default, is enabled globally on the switch. You can configure PTP residency time stamping globally only (see Configure PTP residency time stamping on page 29). Note: Another feature that the switch supports, 802.1AS (audio video bridging, or AVB), is incompatible with PTP residency time stamping on the same switch. For more information, see About audio video bridging on page 16 and the information below. If you must support both PTP residency time stamping and AVB in your network, we recommend that you use two separate switches. Note how PTP residency time stamping and AVB function on the switch: • Mutual exclusion between PTP residency time stamping and AVB: If you add a network profile that is incompatible with PTP residency time stamping, such as Audio AVB, PTP residency time stamping is globally disabled. • AVB takes precedence over PTP residency time stamping: - If you add a network profile that uses AVB (such as Audio AVB), you cannot manually enable PTP residency time stamping. - If PTP residency time stamping is enabled for a network profile (such as the Audio Dante profile) on one port and then you enable a network profile that uses AVB (such as Audio AVB) on another port, PTP residency time stamping is automatically disabled. • PTP residency time stamping can be automatically reenabled: By default, PTP residency time stamping is globally enabled but you can disable it globally. If you disable it and no network profile is using AVB, and then you add a network profile Audio-Video Profile Templates 17 and Network Profiles Audio Video User Manual