NEC Electra Elite IPK II System User Manual page 326

Document Revision 4C Electra Elite IPK II
If multiple BRIs exist and no PRI or T-1 EXTERNAL exists, the system chooses the first BRI that
synchronized with the carrier. In this example, the BRI in S4 synchronized with the carrier first and
became the PLO synchronization source.
Figure 2-9 Digital Trunk Clocking Example 7
In this scenario, the PRI was the clocking source until it went down. There are no other PRIs, T1
(Externals), or BRIs in the system. The IPK II CPU now becomes the PLO synchronization source.
Figure 2-10 Digital Trunk Clocking Example 8
2 - 302 Digital Trunk Clocking