|
|
This chapter describes common Cisco ONS 15200 network configurations. All modules mentioned in this chapter are described in more detail in "Module Descriptions."
The ONS 15200 operates in several network configuration arrangements. All ONS 15200 configurations consist of one or more ONS 15252 Multichannel Units (MCU) or ONS 15201 Single-Channel Units (SCUs). The following information describes some standard ONS 15200 network configurations, including:
In an ONS 15200 system bus configuration, wavelength channels link an ONS 15252 MCU to ONS 15201 SCUs. Use this configuration only in networks where optical-layer fiber protection is unnecessary. It is possible to configure the bus configuration for layer-3 load-sharing protection or client layer 1+1 APS, but the two data traffic flows would need to share the same optical fiber path, and therefore protection would be incomplete.
In the bus configuration, the Client Layer Interface Port (CLIP) modules located in the ONS 15252 MCU and in each ONS 15201 SCU exchange data. Figure 2-1 illustrates the ONS 15200 system bus configuration.
 |
Note The physical connection in Figure 2-1 consists of two fiber-optic cables. |
In the ONS 15200 ring configuration, wavelength channels exist between an ONS 15252 MCU and several ONS 15201 SCUs. A CLIP module installed in the ONS 15252 MCU exchanges data with an associated CLIP module installed in an ONS 15201 SCU.
You can install the ring configuration with or without fiber-optic protection. The ring configuration supports SONET or SDH ring protection and 1+1 APS client-layer protection.You can also arrange the ring configuration to use layer-3 load sharing. Figure 2-2 illustrates the ring configuration with hubbed traffic.
|
Note The physical connection in Figure 2-2 consists of two fiber-optic cables. |
In the dual-home configuration, a pair of ONS 15201 SCUs share the total data traffic load between two different fiber-optic cable (fiber) routes. The pair of ONS 15201 SCUs can use identical or different wavelength channels to communicate with their respective ONS 15252 MCUs. Using identical wavelength channels conserves network resources. In addition to load sharing, the dual-home configuration provides traffic protection in the electronic client-layer domain. If one fiber route is lost, the data traffic shifts to the other fiber route in the client layer.
In addition to protecting traffic at the client layer, the dual-home configuration protects the ONS 15200 system against single MCU or SCU failures. Figure 2-3 illustrates the ONS 15200 dual-home configuration.
|
Note The physical connection in Figure 2-3 consists of two fiber-optic cables. |
In the ONS 15200 multichannel, point-to-point configuration, multiple wavelength channels exist between a pair of ONS 15252 MCUs. You can set up the multichannel point-to-point configuration with or without optical-layer protection. Configuring optical-layer protection requires dual fiber routes.
In the ONS 15200 multichannel, point-to-point configurations, dual fiber routes send information along two separate fiber routes. The dual physical route configuration supports SONET or SDH add/drop multiplexer (ADM) protection and client-layer 1+1 APS protection.
Cisco does not recommend implementing layer-3 load-sharing protection in a multichannel point-to-point configuration because the two network fiber routes need to share an ONS 15252 MCU, and any failure of the ONS 15252 MCU would cause both routes to disappear simultaneously. Figure 2-4 illustrates the ONS 15200 multichannel, point-to-point configurations.
|
Note The physical connection in Figure 2-4 consists of two fiber-optic cables. |
In the ONS 15200 ring configuration with hubbed and meshed traffic, two ONS 15201 SCUs communicate with each other. You can use either unit in a direct point-to-point configuration through a control area network (CAN) bus connection as shown in Figure 2-5, or with a noninterfering ONS 15252 MCU. If you use an ONS 15252 MCU, the MCU must have an installed Bridge module (BM).
To manage a mesh configuration, use the Maintenance Manager (MM) software and associated hardware or use a CAN bus extension cable to connect one of the ONS 15201 SCUs using the meshed channel to the ONS 15252 MCU. An ONS 15201 SCU connected in this way will be on the same logical CAN bus as the ONS 15252 MCU.
In the mesh configuration, you can configure SONET or SDH ADM ring protection on the client side of the meshed channel. If you use client-layer 1+1 APS protection, you must replace each of the ONS 15201 SCUs with a pair of ONS 15201 SCUs transmitting in opposite directions. Figure 2-5 illustrates the ONS 15200 ring configuration with hubbed and meshed traffic.
|
Note The physical connection in Figure 2-5 consists of two fiber-optic fiber cables. |
In the ONS 15200 full-mesh configuration, all ONS 15252 MCUs communicate with each other.
A single Network Control Board (NCB) module located in one of the ONS 15252 MCUs manages the full-mesh configuration. The NCB modules in the other ONS 15252 MCUs are not used; an NCB front cover replaces them.
In the full-mesh configuration, you can configure SONET or SDH ADM ring protection on the client side of the units. Layer-3 load sharing is supported. To implement client-layer 1+1 APS protection, you must replace each of the units with a pair of units transmitting in opposite directions of the ring. Figure 2-6 illustrates the ONS 15200 full-mesh configuration.
|
Note The physical connection in Figure 2-6 consists of two fiber-optic cables. |
Release 1.1 provides the Forward Defect Indication (FDI) switch (fdi_switch), which can be enabled or disabled. When fdi_switch is enabled, the FDI alarm causes the traffic to switch paths. A CLIP receives the FDI alarm if and only if its companion CLIP loses its client-side input signal. The severity of the FDI alarm is minor.
Posted: Thu Apr 17 12:30:42 PDT 2003
All contents are Copyright © 1992--2002 Cisco Systems, Inc. All rights reserved.
Important Notices and Privacy Statement.
