FTL4C1QE1C Finisar QSFP+ 40GBASE-LR4 Transceiver

The Finisar FTL4C1QE1C QSFP+ Optical Module offers an impressive data rate of 40GBASE-LR4. This high-speed data transmission capability is crucial for users who require fast and reliable network connections.

General Information

• Manufacturer: Finisar
• Part Number: FTL4C1QE1C
• Device Type: Optical Transceiver Module

Technical Highlights

• Supports advanced 40GBASE Ethernet connectivity
• Hot-swappable 40GbE QSFP+ interface for seamless integration
• Operates in 4x10GbE mode, linking to four 10GBASE-LR optical channels
• Maximum power consumption under 3.5W LR4
• Environmentally safe with RoHS-6 lead-free compliance

Environmental Range

• Commercial operating temperature: 0°C to 70°C

Fiber Optic Capabilities

• Compatible with single-mode fiber (SMF)
• Maximum transmission reach of 10 km

Multi-rate Support

• Handles data rates from 1.06 Gb/s to 10.5 Gb/s per channel

Compatibility

• Designed for Intel Ethernet Converged Network Adapters

Key Advantages

• Reliable high-speed optical communication
• Energy-efficient with low power dissipation
• Flexible deployment across multiple Ethernet standards

Finisar FTL4C1QE1C QSFP+ Optical Module Transceiver

The Finisar FTL4C1QE1C QSFP+ Optical Module 40GBASE-LR4 Transceiver is a high-performance, hot-pluggable optical transceiver designed for next-generation data center, enterprise backbone, and high-capacity networking environments. Built to support 40 Gigabit Ethernet (40GbE) transmission over single-mode fiber, this module delivers reliable long-range connectivity with superior signal integrity and energy efficiency. As part of the QSFP+ (Quad Small Form-factor Pluggable Plus) family, it integrates four independent 10G channels into a single compact interface, enabling aggregated 40G data throughput while maintaining optimal power consumption and thermal performance.

This transceiver is widely deployed in core switching, aggregation layers, and high-speed interconnect applications where bandwidth density and low latency are critical. Its engineering emphasizes interoperability, long-distance reach, and robust optical performance, making it a key component in modern cloud computing infrastructures, service provider networks, and enterprise-grade fiber optic deployments.

40GBASE-LR4 Technology Architecture and Signal Design

Wavelength Division Multiplexing for Long-Reach Transmission

The 40GBASE-LR4 standard implemented in the Finisar FTL4C1QE1C utilizes coarse wavelength division multiplexing (CWDM) technology to transmit four separate 10Gbps data streams over a single fiber pair. Each channel operates at a distinct wavelength, typically within the 1270 nm to 1330 nm spectral range. This allows simultaneous transmission of multiple signals without interference, significantly increasing fiber utilization efficiency.

At the transmitting side, electrical signals from the host device are converted into optical signals using four integrated laser transmitters. These optical streams are then multiplexed into a single optical output and transmitted across single-mode fiber. On the receiving side, the optical signal is demultiplexed into four individual wavelengths, each converted back into electrical signals for processing by the host system.

Parallel Optical Channel Design

The architecture of the QSFP+ LR4 module is built around four parallel optical lanes, each operating at 10.3125 Gbps to support full 40G Ethernet throughput. This parallelism ensures consistent data distribution, reduces latency, and enhances signal stability over long distances. The design also minimizes bit error rates by maintaining strict channel isolation and optical alignment precision.

The module's internal optical engine integrates high-performance lasers, photodetectors, and signal conditioning circuitry, enabling it to maintain signal integrity even in complex routing environments. This makes it suitable for demanding enterprise and carrier-grade networking scenarios.

Optical Stability

Finisar is recognized for its advanced optical component engineering, and the FTL4C1QE1C QSFP+ transceiver reflects this expertise through its precision-manufactured optical assembly. The module is designed to maintain consistent optical output power and receiver sensitivity across varying environmental conditions. This ensures stable data transmission even in high-density switch environments where thermal fluctuations may occur.

The internal components are optimized for low insertion loss and high return loss performance, enabling efficient signal transmission over distances up to 10 kilometers on single-mode fiber. This long-reach capability is essential for campus interconnects, metropolitan area networks, and data center inter-building links.

Thermal Efficiency and Power Optimization

The QSFP+ form factor is engineered for low power consumption, typically operating under 3.5W depending on host system configuration and environmental conditions. The Finisar FTL4C1QE1C is designed with advanced power management circuits that dynamically regulate energy usage while maintaining optimal optical performance.

Thermal dissipation is managed through a compact metal enclosure that ensures efficient heat transfer to the host chassis. This enables the module to function reliably in high-density switch configurations without overheating or performance degradation.

Compatibility and Interoperability

Multi-Vendor Network Integration

The Finisar FTL4C1QE1C QSFP+ Optical Module is designed for broad interoperability across major networking equipment manufacturers. It is commonly used in switches, routers, and optical transport systems that support 40GBASE-LR4 QSFP+ interfaces. Its standardized design ensures compatibility with platforms from leading vendors in enterprise and carrier networking ecosystems.

This interoperability reduces vendor lock-in and allows network engineers to deploy scalable optical solutions across heterogeneous infrastructures. The module adheres to IEEE 802.3ba standards, ensuring consistent performance and predictable behavior across compliant systems.

Hot-Pluggable QSFP+ Interface Architecture

The QSFP+ interface allows for hot-swappable installation, enabling modules to be inserted or removed without powering down the host system. This feature is essential for minimizing network downtime and maintaining continuous service availability in production environments.

The edge connector design ensures secure electrical contact with the host system while maintaining signal integrity at high data rates. This makes the module suitable for mission-critical applications where uninterrupted connectivity is required.

Optical Performance Characteristics

Transmission Distance and Signal Integrity

The Finisar FTL4C1QE1C is optimized for long-reach optical communication over single-mode fiber, typically supporting distances up to 10 kilometers. This range is achieved through high-power distributed feedback (DFB) lasers and highly sensitive photodetectors that ensure minimal signal degradation over extended fiber runs.

Signal integrity is maintained through advanced error correction and tight wavelength control, reducing dispersion and chromatic distortion effects that commonly impact long-distance optical transmission. This makes the module highly reliable for backbone interconnects and distributed data center architectures.

Receiver Sensitivity and Optical Budget Efficiency

Receiver sensitivity is a critical performance parameter for LR4 transceivers, and the Finisar module is engineered to detect low-power optical signals while maintaining low bit error rates. The optical budget is optimized to ensure compatibility with standard single-mode fiber infrastructure without requiring additional amplification under normal operating conditions.

This efficiency reduces deployment costs and simplifies network design by eliminating the need for complex optical signal regeneration equipment in many use cases.

Data Center and Enterprise Networking Applications

High-Speed Spine and Leaf Architectures

In modern data center architectures, the Finisar FTL4C1QE1C QSFP+ module is commonly deployed in spine-leaf network topologies. These architectures require high-bandwidth, low-latency interconnects between aggregation and core switches. The 40GBASE-LR4 capability enables efficient traffic aggregation and distribution across large-scale virtualized environments.

Its ability to support long-distance transmission allows data centers to extend connectivity across multiple buildings or campus environments without sacrificing performance or reliability.

Cloud Computing and Virtualized Infrastructure

Cloud service providers rely heavily on high-density optical interconnects to support virtual machine migration, distributed storage replication, and real-time application delivery. The Finisar QSFP+ LR4 module provides the necessary bandwidth and stability to support these workloads, ensuring seamless data flow between compute clusters and storage systems.

Its consistent latency performance is particularly important in virtualization environments where microsecond-level delays can impact application responsiveness.

Hot-Swap Deployment Process

The installation process for the Finisar FTL4C1QE1C module is designed for simplicity and operational efficiency. Network engineers can insert the module directly into a compatible QSFP+ port without system shutdown. Once installed, the host system automatically recognizes the transceiver and initiates link training and optical calibration.

This plug-and-play functionality reduces maintenance windows and allows for rapid scaling of network capacity in response to increasing bandwidth demands.

Fiber Optic Requirements

Single-Mode Fiber Compatibility

The Finisar FTL4C1QE1C is designed exclusively for single-mode fiber (SMF) applications, typically utilizing LC duplex connectors. Single-mode fiber provides low attenuation and minimal dispersion, making it ideal for long-distance high-speed transmission.

The LC connector interface ensures secure physical alignment and low insertion loss, contributing to stable optical performance across long cable runs. Proper fiber cleanliness and connector maintenance are essential to achieving optimal signal quality.

Wavelength Stability and Channel Isolation

Each of the four CWDM channels operates at a tightly controlled wavelength to prevent inter-channel interference. Temperature compensation mechanisms within the module ensure stable wavelength output even under varying environmental conditions. This stability is critical for maintaining consistent performance across large-scale optical networks.

Reliability, Compliance, and Industry Standards

IEEE and MSA Compliance

The Finisar FTL4C1QE1C QSFP+ module complies with IEEE 802.3ba standards for 40 Gigabit Ethernet, ensuring interoperability and predictable performance across compliant networking equipment. It also adheres to Multi-Source Agreement (MSA) specifications for QSFP+ form factors, enabling cross-vendor compatibility.

Environmental and Operational Durability

The module is designed to operate in demanding enterprise environments with strict thermal and electrical constraints. It maintains stable performance across standard data center temperature ranges and is engineered for long operational lifespans under continuous usage conditions.

Its robust construction and strict quality control processes ensure high reliability, making it suitable for mission-critical deployments in telecommunications and cloud infrastructure.

High-Density Networking Optimization

The compact QSFP+ design of the Finisar FTL4C1QE1C allows for high port density in modern switches, enabling efficient scaling of 40G connectivity without increasing rack space requirements. This contributes to improved airflow management and energy efficiency in data center environments.

Scalable Infrastructure Integration

As network demands continue to grow, the modular nature of QSFP+ transceivers allows infrastructure to be upgraded incrementally. The Finisar LR4 module supports this scalability by providing a reliable and standardized 40G optical interface that can be deployed across existing fiber infrastructure with minimal redesign.