The demand for network bandwidth continues to accelerate rapidly, forcing network operators and enterprise managers to squeeze maximum capacity out of their existing optical fiber infrastructure. Laying new fiber cables is often cost-prohibitive or physically impractical, making single-fiber bidirectional transmission a critical strategy for optical network scaling.

Cisco addresses this operational challenge with its advanced coherent pluggable transceiver portfolio. By bringing 400G bidirectional capability to a standardized CFP2 footprint, operators can effectively double their fiber utilization without altering physical fiber paths or investing in costly line-card overhauls.

Product overview

The Cisco 400G Digital Coherent Bidirectional (BiDi) CFP2 module is designed to transmit and receive 400G optical signals simultaneously over a single strand of fiber. It accomplishes this by splitting the optical spectrum into two separate wavelength bands, allowing bidirectional traffic to flow without interference on one fiber core.

This solution relies on two complementary product variants that work in pairs across the optical link: the Cisco 400G BiDi CFP2 module operating with Transmit Band A / Receive Band B, and its counterpart operating with Transmit Band B / Receive Band A (commonly designated as Cisco 400G-CFP2-BIDI-1 and 400G-CFP2-BIDI-2). Both modules feature an integrated Digital Signal Processor (DSP), delivering high-performance coherent transmission directly from a pluggable form factor.

These transceivers are ideal for metro aggregation, access networks, and data center interconnects (DCI) where fiber availability is constrained. By plugging directly into compatible Cisco switching and routing line cards, they provide a simple, scalable, and operationally efficient path to high-density 400G transport.

Features and benefits

• Single-Fiber Transmission: Doubles network capacity over existing single-fiber infrastructure by enabling full-duplex 400G traffic over a single optical strand.
• Integrated Digital Signal Processor (DSP): Features a built-in coherent DSP within the CFP2-DCO module, streamlining platform integration and eliminating external host DSP requirements.
• Flexible Modulation Support: Utilizes advanced coherent modulations (such as 16QAM and QPSK) to balance performance, reach, and optical capacity according to network requirements.
• Advanced Forward Error Correction (FEC): Incorporates high-gain FEC (oFEC) to maintain optical signal integrity and extend reach across challenging link distances.
• Significant Cost Savings: Substantially reduces CapEx and OpEx by eliminating the need to lease or deploy additional fiber lines.
• Cisco Platform Compatibility: Fully supported across a wide range of Cisco routing and optical platforms designed for CFP2-DCO optical interfaces.