Chapter 1 General Troubleshooting

Network Troubleshooting Tests

1.1 Network Troubleshooting Tests

Use loopbacks and hairpins to test newly created circuits before running live traffic or to logically locate the source of a network failure. All ONS 15327 line (traffic) cards, except Ethernet cards, allow loopbacks and hairpins.

Caution On OC-N cards, a facility loopback applies to the entire card and not an individual circuit. Exercise caution when using loopbacks on an OC-N card carrying live traffic.

A facility loopback tests the line interface unit (LIU) of a card, the mechanical interface card (MIC), and related cabling. After applying a facility loopback on a port, use a test set to run traffic over the loopback. A successful facility loopback isolates the LIU, the MIC, or the cabling plant as the potential cause of a network problem. Figure 1-1shows a facility loopback on an XTC-14 or XTC-28-3 card.

Figure 1-1 Facility Loopback Process on an XTC Card

 

 

XTC

Test Set A

MIC

OC-N

 

DS-N

 

 

DS-N

 

Facility

 

76186

loopback

 

 

 

To test the LIU on an OC-N card, connect an optical test set to the OC-N port and perform a facility loopback or use a loopback or hairpin on a card that is farther along the circuit path. Figure 1-2shows a facility loopback on an OC-N card.

Caution Before performing a facility loopback on an OC-N card, make sure the card contains at least two data communications channel (DCC) paths to the node where the card is installed. A second DCC provides a nonlooped path to log into the node after the loopback is applied, thus enabling you to remove the facility loopback. Ensuring a second DCC is not necessary if you are directly connected to the

ONS 15327 containing the loopback OC-N card.

Figure 1-2 Facility Loopback Process on an OC-N Card

Test Set

OC-N

XTC

OC-N

 

 

90642

A terminal loopback tests a circuit path as it passes through the XTC card and loops back from the card with the loopback. Figure 1-3 on page 1-3shows a terminal loopback on an OC-N card. The test-set traffic comes in on the MIC card DS-N ports and goes through the XTC card to the OC-N card. The

Cisco ONS 15327 Troubleshooting Guide, R3.4

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April 2003

 

 

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Cisco Systems ONS 15327 manual Network Troubleshooting Tests, Facility Loopback Process on an XTC Card

ONS 15327 specifications

Cisco Systems ONS 15327 is a high-performance optical networking solution tailored for service providers and enterprises looking to enhance their optical communication infrastructure. This versatile platform is recognized for its robust performance, scalability, and flexibility, making it suitable for a wide array of applications ranging from broadband access to metropolitan area networking.

One of the standout features of the ONS 15327 is its ability to handle multiple data types over a single platform. It supports a rich array of protocols, including Ethernet and SONET/SDH, allowing service providers to deliver a diverse portfolio of services to their customers. This multiservice capability simplifies the network architecture, reducing operational complexity and costs.

The ONS 15327 is designed with a modular architecture, which enables operators to customize and scale their network as demand grows. It supports a variety of card options for different media types, wavelengths, and capacity requirements. This modularity not only facilitates straightforward upgrades but also allows for efficient network management.

In terms of technology, the ONS 15327 leverages dense wavelength division multiplexing (DWDM) capabilities to maximize the utilization of available fiber bandwidth. This allows for an impressive increase in transmission capacity without the need for additional fiber installations, making it a cost-effective solution for expanding networks.

Another significant characteristic of the Cisco ONS 15327 is its advanced performance monitoring and management features. Built-in diagnostic tools provide real-time visibility into network performance, enabling prompt identification and troubleshooting of potential issues. This proactive approach to network management enhances service reliability and customer satisfaction.

Security is also paramount in the ONS 15327. The platform integrates various security features and protocols to protect the data traversing the network, ensuring compliance with industry standards and safeguarding sensitive information.

Furthermore, the equipment is designed for easy integration into existing infrastructures. Its compatibility with Cisco’s broader networking solutions allows for seamless interconnection with routers, switches, and other devices, facilitating comprehensive network solutions.

In conclusion, Cisco Systems ONS 15327 stands out as a powerful optical networking platform that combines versatility, scalability, and advanced management features. Its ability to support various protocols and harness optical technologies makes it an essential tool for organizations aiming to optimize their telecommunications infrastructure while minimizing costs and complexity.