Configuring Channelized OC Modules > Overview

Overview

OC modules provide high-speed communications between E-series routers and core routers in an ATM network. You can configure two versions of channelized OC (cOC) modules using the NMC-RX application: cOC3 and cOC12.

In E-series devices, OC line modules pair with I/O modules to provide particular capabilities and connections. For more information about channelized OC modules, see Table 33 and the JUNOSe Physical Layer Configuration Guide.

 Table 33:  Channelized OC Line Modules and I/O Modules

 Line Module
 I/O Module
 Description
 NMC-RX Software Reference Name

 cOCx/STMx

 cOC3/STM1

 4-port, channelized 
OC3/STM1 for Frame Relay

 COC3 FRAME-4 port


 

 cOC12/STM4

 1-port, channelized
OC12/STM4 for Frame Relay

 COC12 FRAME-1 port



 

DS3 and DS1 interfaces are not automatically created on cOCx modules—you must manually create them. You can stack DS3 and DS1 interfaces in multiple ways (see Figure 12).

You can designate a cOCx line module for TI or E1 connections. Mapping to T1 or E1 does not affect the device; however, the operation mode of the DS1 interfaces that you created on the line module is set to T1 or E1.

Figure 12: cOC3 Line Module Stacking Example

Example 1

In Figure 12, ports 1 and 2 have cOC3 line interfaces configured with SDH mode. In SDH mode, you can create SONET paths of OC1/STM0 or OC3/STM1 speed. All OC3-speed SONET paths have three DS3 channels that indicate the DS3 channel number of the DS1 interfaces that are created on them. On OC1-speed SONET paths, the DS3 channel is always 1. There are no DS3 interfaces on port 1 in this example, because you cannot create DS3 interfaces on OC3-speed SONET paths.

Example 2

Port 2 has an OC1-speed SONET path on a cOC3 line interface in SDH mode. SONET path 1 has a channelized DS3 interface, which has 28 DS1 interfaces that are automatically generated when you create the DS3 interface. There are 28 DS1 interfaces because the module is mapped to T1 operation mode. If you map the card to an E1 line module, you cannot create DS3 interfaces.

Example 3

SONET path 2 on port 2 has an unchannelized DS3 interface with no DS1 interfaces (DS1 interfaces cannot exist on unchannelized DS3 interfaces). Instead, you can create Cisco HDLC, Frame Relay, and PPP directly on unchannelized DS3 interfaces.