The Cisco® ONS 15454 Multiservice Transport Platform (MSTP) offers enhanced optical amplifiers for extending the reach of a metro, regional, or long-haul network. The optical amplifier cards are part of the Cisco ONS 15454 MSTP intelligent dense wavelength-division multiplexing (DWDM) architecture engineered to reduce DWDM complexity and speed the deployment of next-generation networking solutions.

The Cisco ONS 15454 Enhanced C-Band 96 Channel Amplifier card (Figure 1) is a plug-in module that takes advantage of the proven Cisco ONS 15454 carrier-class features. It delivers the reach and optical performances to support a single DWDM channel all the way to 96 channels today, to meet the requirements of service provider and enterprise networks. Table 1 outlines the enhanced C-band optical amplifier plug-in card types available for the Cisco ONS 15454 MSTP with the applications they are designed to support.

Features and Benefits
The Cisco True Variable Gain Booster Amplifiers, with maximum 17- and 24-dB gain are high-power enhanced amplifiers suited for the needs of a next generation of optical networks. The coherent detection technology and a new modulation format like the PM-DQPSK modulation scheme employed in 40- and 100-Gbps transponder units of the recent high-capacity optical networks eliminate the need for dispersion compensation. The noise figure of these erbium-doped fiber amplifiers (EDFAs) is thus optimized by having a single amplification stage with no need for a lossy midstage access to provision dispersion-compensating units. Looking forward, the channel capacity is expected to grow beyond the current 80 channels to a 96-channel total. These amplifiers can also support the amplification of up to 96 channels in the C-band of the spectrum – 50-GHz-spaced ITU grid (wavelength range from 1528.77 to 1566.72 nm).

The 17- and 24-dB amplifiers take advantage of the latest in amplifier technology, variable optical attenuators, photo diodes, and extensive software to facilitate a high degree of automation for simplified operations. They feature a low-noise-gain block for C-band optical amplification requirements with an embedded gain-flattening filter. For flexibility of application support, the amplifiers support two modes of operation – constant gain and constant power – while also providing Amplified Spontaneous Emission (ASE) compensation in either modes. They also provide fast-transient suppression to respond quickly to network changes without adding impairments and degradation. Both cards allow a programmable tilt and possess a non-distorting low-frequency transfer function. Each card integrates software-controllable variable optical attenuators (VOAs) along with extensive optical monitoring with photo diodes, to provide nodal- and network-based automatic power-level management. Extensive optical safety algorithms provide user safety when operating the network. The optical amplifier cards incorporate faceplate-mounted LEDs to provide a quick visual check of the operational status at the card. Printed on each of the faceplates is an icon, an orange circle, which corresponds to shelf-slot icons located on the shelf assembly; it indicates the shelf slot where the cards can be inserted. The cards are supported by the integrated Cisco Transport Controller, a craft manager, which provides the user access for operations, administration, maintenance, and provisioning (OAM&P) for the system. Figure 2 depicts the functional block diagram of both amplifiers.