Multi-clock PTP profile interworking allows the 7705 SAR to interwork multiple PTP profile combinations with a mix of IP and Ethernet encapsulations. With multi-clock PTP profile interworking, there are two active PTP clocks in the system: one PTP clock with Ethernet encapsulation (clock-id parameter set to csm) and one PTP clock with IP encapsulation (clock-id parameter set to 1 to 12). Multi-clock interworking is supported on the 7705 SAR-8 and 7705 SAR-18 on 8-port Gigabit Ethernet Adapter cards and 6-port Ethernet 10Gbps Adapter cards.
To assign a clock profile to be the primary clock, configure the system time to recover time from its clock ID with the config>system>time>ptp>clock command. To assign a clock profile to be the alternate clock, enable the use-node-time command on its clock ID. The alternate clock uses the timing reference recovered from the primary profile clock.
If the Ethernet encapsulated clock is the primary clock (the main router clock), the IP encapsulated clock must be the alternate clock that uses the primary clock as reference. The reverse is true if the IP encapsulated clock is the primary clock.
If the node time clock is based on the integrated GNSS, both PTP clocks can be master clocks for their respective profiles. In this scenario, there is no profile interworking because there is no way to determine which clock is the primary clock and which is the alternate clock.
The primary clock can be a master, boundary, or slave. The alternate clock must be configured to be a master for multi-clock PTP profile interworking.
The supported profile combinations are:
primary profile is G.8275.2 (IP encapsulation) and alternate profile is G.8275.1 (Ethernet encapsulation)
primary profile is G.8275.2 (IP encapsulation) and alternate profile is IEC/IEEE 61850-9-3 (Ethernet encapsulation)
primary profile is G.8275.2 (IP encapsulation) and alternate profile is C37.238-2017 (Ethernet encapsulation)
primary profile is G.8275.1 (Ethernet encapsulation) and alternate profile is G.8275.2 (IP encapsulation)
The frequency reference used by the alternate PTP clock is based on the SETS configuration which can be the integrated GNSS, PTP, or any other acceptable frequency reference available on the 7705 SAR. G.8275.1 PTP is not a valid reference for frequency.