Chapter 6: System Control Module (SCM)
STANDARD Revision 1.0 C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved. 167
SCM/SCM II Ethernet Interfaces
The Ethernet connection must be at least a 10 baseT and half duplex connection. There is only one port but it can be
reached through either one of two RJ45 connectors — one in front and one in back. Only one of these maintenance
Ethernet interfaces on the SCM/SCM IIs may be used at a time.
SCM 3 Ethernet Interfaces
While the SCM 3 Ethernet interfaces are in the same location as those of the SCM and SCM II, the implementation is
different. As on the prior SCMs, the Link/Activity LED’s reside on the SCM 3 front panel. For the SCM 3, however, these
Link/Activity LEDs only reflect the status of the front panel ethernet interface. The SCM PIC-resident ethernet interface
does not have Link/Activity LEDs.
The software will support:
One of the SCM 3 physical ethernet interfaces as active/operational at a time and they will share the SCM MAC address
between them.
The SCM 3 will provide the ability to select either the front or the rear Ethernet port as the active/operational port.
The selection of the (front/rear) port will happen at boot time using the same "menu" as the Ethernet port IP address,
subnet, and gateway.
The setting of the active/operational Ethernet port (front/rear) is printed to the console port during boot, stored in the
SCM PIC (with fan controller), and is persistent across reboots.
A single Ethernet port directional setting applies to both SCM 3s if the system is a duplex system.
For newly manufactured SCM PICs (with fan controllers), the default orientation will have the rear Ethernet port being
active/operational.
Legacy/existing SCM PICs will also have the default orientation of the rear Ethernet port active/operational.
Slots 19 and 20 are reserved for the SCM cards on the C4 CMTS and Slot 19 for the C4c CMTS.
Removing the SCM in a simplex configuration (one SCM) will shut down the CMTS. The SCM provides the ON/OFF power
control for all client modules (CAMs) in the CMTS. If the simplex SCM is removed, then the power converters on all client
modules are shut off.