Setup guide

4-8
Cisco 6400 Software Setup Guide
OL-1183-04
Chapter4 Node Line Card Interface Configuration
NLC Interface Clocking
Input cells: 264089 Output cells: 273253
5 minute input rate: 0 bits/sec, 0 cells/sec
5 minute output rate: 0 bits/sec, 0 cells/sec
Input AAL5 pkts: 172421, Output AAL5 pkts: 176993, AAL5 crc errors: 0
NLC Interface Clocking
Each NLC port can be configured to support the following clocking options:
• Free-running—Transmit clock is derived from the local oscillator on the NLC port, with stratum
level 4 accuracy.
• Loop-timed—Transmit clock is derived from the receive (rx) clock.
• Network-derived (default)—Transmit clock is derived from the port system clock specified at
highest priority by the network-clock-select global configuration command.
For detailed information on network clocking, see the “Network Clocking” section on page2-14.
Configuring the NLC Interface Clock
To select the transmit clock source for a port, complete the following steps, beginning in global
configuration mode:
Example
In the following example, ATM 4/0/0 is configured with a network-derived transmit clock source:
!
network-clock-select 1 atm 2/0/0
network-clock-select 2 atm 2/0/1
network-clock-select 3 atm 1/0/0
!
interface atm 4/0/0
clock source network-derived
!
OC-3 NLC and OC-12 NLC Interface Options
The OC-3 NLC and OC-12 NLC support the following Synchronous Optical Network (SONET) and
Synchronous Digital Hierarchy (SDH) framing modes:
• STM-1—Synchronous Transport Module level 1. One of a number of SDH formats that specifies
the frame structure for the 155.52-Mbps lines used to carry ATM cells.
• STS-3c—Synchronous Transport Signal level 3, concatenated. SONET format that specifies the
frame structure for the 155.52-Mbps lines used to carry ATM cells. (Default for OC-3 NLC.)
• STM-4—Synchronous Transport Module level 4. SDH/STM-4 operation (ITU-T specification).
Command Purpose
Step1
Switch(config)# interface atm slot/subslot/port
Selects the interface to be configured.
Step2
Switch(config-if)# clock source {free-running |
loop-timed | network-derived}
Configures the interface network clock source.