Cisco Systems 15216 EDFA2 manual Bandwidth On Demand, Wavelength Protection Switching

F I N A L D R A F T - C I S C O C O N F I D E N T I A L

C H A P T E R 1

Applications

This manual describes how to install and operate the Cisco Optical Network System (ONS) 15216 Erbium-Doped Fiber Amplifier 2 (EDFA2). The ONS 15216 EDFA2 is an optical amplifier that enables the migration to next-generation all-optical networks. It features bandwidth-on-demand and wavelength protection switching that extend dense wavelength division multiplexing (DWDM) links by hundreds of kilometers.

With the ONS 15216 EDFA2, optical signals from a span in a DWDM network can be added or dropped without negatively affecting (degrading) other optical signals on the same span.

1.1 Bandwidth On Demand

The ONS 15216 EDFA2 is a technology for bandwidth-on-demand wavelength services. Depending on the settings and the input power, every wavelength in a ONS 15216 EDFA2 is guaranteed to be amplified by 13 to 22 dB. With the ONS 15216 EDFA2’s gain control technology, amplification for each wavelength remains constant at all times as wavelengths are added or dropped from an optical fiber. As long as the total (composite) input power of all wavelengths is between 4 dBm and –27 dBm, any number of wavelengths can be amplified.

1.2 Wavelength Protection Switching

The ONS 15216 EDFA2 uses wavelength protection switching to restore wavelengths that are lost in the event of a fiber cut or other loss of signal. Figure 1-1 on page 1-2shows an example of wavelength protection switching. In this example, two wavelengths are routed clockwise around a metro ring, and two wavelengths are routed counter-clockwise around the same ring. Of the two counter-clockwise wavelengths, only one transits the span linking locations D and C. If a fiber cut occurred on this span, the affected wavelength could be restored by rerouting it (clockwise) around the ring to location D. Wavelength protection switching minimizes the amount of bandwidth allocated for restoration because only the affected wavelength is restored, not the entire fiber.

Cisco ONS 15216 EDFA2 Operations Guide

78-16033-01 1-1