Making External Clock Connections - Cisco BPX-BXM-155-8DX Installation And Configuration Manual

Chapter 15 Connecting Temporary Terminal and Attaching Peripherals

Making External Clock Connections

Making External Clock Connections
If you want to synchronize the BPX switch to some other external equipment or a local digital central
office, you can use one of two connectors on an BCC15-BC or BPX-BCC-3-BC backcard to accept a
clock input.
You can use a DB15 connector labeled EXT TMG to connect a balanced T1 or E1 signal, synchronized
from some higher-level source to the BPX switch. If an unbalanced 75-ohm E1 signal is available as
the timing source, a BNC EXT TMG connector is also provided.
For a BCC-3-BC backcard (backcard for BCC-3-32M, BCC-3-64M, or BCC-4V), you can use a DB15
connector labeled EXT 1 TMG to connect a balanced T1 or E1 signal, synchronized from some
higher-level source to the BPX switch.
The EXT 2 TMG connector provides a redundant connector to EXT 1 TMG. A T1 source with 100 ohm
impedance or an E1 source with 100/120 ohm impedance typically uses this connector. If an unbalanced
75-ohm E1 signal is available as the timing source, a BNC EXT TMG connector is also provided.
The BPX switch can use these inputs rather than its internal Stratum 3 clock source.
Note Contact Cisco Customer Service for information on setting up either a 75-ohm or 120-ohm
clock interface on the BCC backcard.
Cisco BPX 8600 Series Installation and Configuration
15-16
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001