ADC CUDA 3 - Manual (Page 132)

ADC Telecommunications, Inc.
130 C HAPTER 7: P ACKET O VER SONET A DMINISTRATION
Clock Source
SONET is a synchronous transport technology. Timing for this synchronous
transmission of data is derived from one of the following clock sources:
■
Line — Also referred to as loop timing, this timing option configures the
interface to use the recovered receive clock to provide transmit clocking.
This is the default clock source.
■
Internal — Configures the interface to generate the transmit clock
internally.
Keep in mind that the clock source you configure for the POS interface can
also be used as the clock source for the primary or secondary backplane
clock. If you want to use the clock source for the POS interface as the clock
source for the primary or secondary backplane clock, you must configure the
Line clock source for the POS interface. Refer to “Configuring Clock
Sources” on page 86 for more information on backplane clocks.
To configure the clock source for a selected POS interface, perform the
following task in interface pos <c/s/i> mode:
When configuring point to point links, one side of the link should be
configured to utilize a line clock source, the other should utilize an internal
clock source.
Signal Type
Configures the type of signal (framing) this POS interface transmits.
Currently, the system supports only SONET STS-n framing.
To configure the framing type used on a POS interface, perform the
following task in interface pos <c/s/i> mode:
Task Command
Configure the clock source for the
current interface. clock-source {line | internal}
Task Command
Configure POS framing. pos framing {sonet | sdh}