Chapter 3 Installing a Cisco 7200 VXR Router

Connecting I/O Controller, NPE-G1, or NPE-G2 Cables

Note The 1000BASE-ZX GBIC provides an optical power budget of 21.5 dB. You should measure your cable plant with an optical loss test set to verify that the optical loss of the cable plant (including connectors and splices) is less than or equal to 21.5 dB. The optical loss measurement must be performed with a 1550-nm light source.

Mode-Conditioning Patch Cord Description

Amode-conditioning patch cord can be used with the WS-G5486= or GBIC-LX/LH= to allow reliable laser transmission between the single-mode laser source on the GBIC and a multimode optical fiber cable.

When an unconditioned laser source designed for operation on single-mode optical fiber is directly coupled to a multimode optical fiber cable, an effect known as differential mode delay (DMD) might result in a degradation of the modal bandwidth of the optical fiber cable.

This degradation results in a decrease in the link span (the distance between a transmitter and a receiver) that can be supported reliably. The effect of DMD can be overcome by conditioning the launch characteristics of a laser source. A practical means of performing this conditioning is to use a device called a mode-conditioning patch cord.

A mode-conditioning patch cord is an optical fiber cable assembly that consists of a pair of optical fibers terminated with connector hardware. Specifically, the mode-conditioning patch cord is composed of a single-mode optical fiber permanently coupled off-center (see Offset in Figure 3-19) to a graded-index multimode optical fiber. Figure 3-19shows a diagram of the mode-conditioning patch cord assembly.

Figure 3-19 GBIC Mode-Conditioning Patch Cord Assembly

 

 

 

 

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A mode-conditioning patch cord assembly is composed of duplex optical fibers, including a single-mode-to-multimode offset launch fiber connected to the transmitter, and a second conventional graded-index multimode optical fiber connected to the receiver. The use of a plug-to-plug patch cord maximizes the power budget of multimode 1000BASELX and 1000BASELH links.

Cisco 7200 VXR Installation and Configuration Guide

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Cisco Systems 7200 VXR manual Gbic Mode-Conditioning Patch Cord Assembly

7200 VXR specifications

The Cisco Systems 7200 VXR Series is a robust and highly scalable modular router designed to meet the demands of service providers and enterprises seeking high-performance solutions for their network infrastructures. Launched as part of the Cisco 7200 series, the VXR (Virtual Extensible Routing) variant enhances capabilities while providing effective support for a wide range of applications, including Internet Protocol (IP) routing, Voice over IP (VoIP), and Virtual Private Network (VPN) configurations.

At the core of the 7200 VXR is its modular design, which enables network administrators to customize the router according to their specific needs. The router supports a variety of interface cards, processing engines, and power supply options, ensuring flexibility for diverse network environments. This modularity facilitates easy upgrades and expansions, making it ideal for growing enterprises and service providers looking to future-proof their networks.

One of the standout features of the Cisco 7200 VXR is its impressive routing performance. It can handle a high level of traffic with low latency, which is critical for bandwidth-intensive applications. The router supports a wide array of routing protocols, including Border Gateway Protocol (BGP), Open Shortest Path First (OSPF), and Integrated Intermediate System-to-Intermediate System (IS-IS), providing versatility for various network topologies.

The 7200 VXR also incorporates advanced features for enhanced security and reliability. With support for IPsec VPNs, it enables secure data transmission across untrusted networks. The router also includes features like Quality of Service (QoS) for prioritizing network traffic, ensuring critical applications receive the bandwidth they require even during peak loads.

In terms of scalability, the Cisco 7200 VXR can support hundreds of thousands of routes and MAC addresses, making it suitable for large metropolitan area networks (MANs) as well as enterprise backbone applications. It also provides the capability to support IPv4 and IPv6 networks, preparing organizations for a transition to next-generation internet protocols.

Additional characteristics of the Cisco 7200 VXR include enhanced manageability through the Cisco IOS software, which offers a comprehensive command-line interface and support for network management protocols. The router is also energy-efficient, with options for redundant power supplies that ensure continuous availability and minimal downtime in mission-critical applications.

Overall, the Cisco Systems 7200 VXR represents a powerful solution that combines performance, scalability, and security, making it an excellent choice for organizations looking to enhance their network capabilities in a rapidly evolving technological landscape.