Understanding Circuit Emulation PIC Clocking Features

All Circuit Emulation PICs support the following clocking features:

• External clocking—Also known as loop timing. Clock is distributed via TDM interfaces.
• Internal clocking with external synchronization—Also known as external timing or external synchronization.
• Internal clocking with PIC-level line synchronization—The PIC’s internal clock is synchronized with a clock recovered from a TDM interface local to the PIC.

This feature set is useful for aggregation in mobile backhaul applications.

Note: The primary reference source (PRS) of the clock recovered from one interface may not be the same as that of another TDM interface. There is a limitation on the number of timing domains that can be supported in practice.