Selecting Between 40G QSFP+ MTP vs 40G QSFP+ LC Transceivers: A Comprehensive Guide

What is a 40G QSFP+ MTP Transceiver?

Basic Introduction of 40G QSFP+ MTP Transceiver

Crafted to address the needs of contemporary high-density networks, the 40G QSFP+ MTP transceiver seamlessly integrates a compact design with unparalleled speed. Leveraging the QSFP+ (Quad Small Form-factor Pluggable Plus) standard, this optical module operates at 40 gigabits per second (Gbps), ensuring compatibility and exceptional performance.

Its standout feature lies in utilizing MTP (Multi-fiber Push-in/Pull-out) connectors, a groundbreaking addition consolidating multiple fibers into a singular interface. This innovative breakthrough not only simplifies cable management but also caters to the requirements of parallel optical applications. It is the prime choice for data center environments in pursuit of swiftness, space efficiency, and flawless connectivity.

 

Transceiver Type with MTP Connector

40GBASE-SR4: The 40G SR4 transceiver utilizes MTP connectors and operates over multimode fiber. It supports short-range transmissions up to approximately 100 meters, commonly employed for high-speed connectivity within data centers or interconnecting racks.

 

40GBASE-CSR4: CSR4 (Cisco Short Reach) transceivers also use MTP connectors. They're optimized for extended reach on multimode fibers, allowing connections of up to 300 meters, making them suitable for more extensive data center setups or inter-building connectivity.

 

40GBASE-PLR4: PLR4 (Parallel Long Range) transceivers with MTP connectors operate over single-mode fiber, enabling long-range connectivity of up to 2 kilometers. They are often used for longer-distance transmissions in environments where significant distances, such as campus or metropolitan networks, need to be covered.

 

40GBASE-UNIV: Universal transceivers are versatile and designed to support multimode and single-mode fibers. These transceivers offer flexibility in various networking setups where the type of fiber may vary, allowing for adaptation to different distances and network configurations.

 

What is a QSFP+ 40G LC Transceiver?

 

Basic Introduction of 40G QSFP+ LC Transceiver

 

The 40G QSFP+ LC transceiver is an advanced optical communication module for high-speed data transmission in networking environments. It operates using LC connectors and can transfer data at 40 gigabits per second (Gbps). This transceiver is commonly used in networking equipment to facilitate quick and reliable communication between devices, offering a compact yet powerful solution for efficiently handling large volumes of data. Its compatibility and efficiency make it a crucial component in modern networking infrastructures requiring high-speed connectivity.

Transceiver Type with LC Connector

40GBASE-LR4 utilizes LC UPC Duplex SMF Fiber Optic Patch Cables to achieve reliable 40 Gigabit Ethernet connections over single-mode fiber, spanning up to 10 kilometers. The 40G LR4 transceiver employs four wavelengths for simultaneous data transmission and reception, ensuring robust long-distance communication.

40GBASE-LR4L is tailored for shorter reach applications, maintaining the 40Gbps data rate but optimized for links up to 2 kilometers. Like the LR4 variant, it uses LC connectors and single-mode fiber optic cables, providing a cost-effective solution for shorter-distance deployments.

40GBASE-BiDi introduces bi-directional capabilities, enabling 40 Gigabit Ethernet transmission over a single LC fiber pair on duplex single-mode fiber. It leverages wavelength division multiplexing (WDM) technology, allowing bidirectional data flow on the same fiber strand, simplifying network architecture, and reducing fiber usage.

40GBASE-ER4 is engineered for extended-range applications, supporting 40 Gigabit Ethernet connections over significantly longer distances, typically up to 40 kilometers. Utilizing LC connectors and single-mode fiber, it employs advanced optics and signal processing for reliable data transmission across extensive network spans.

QSFP+ MTP vs QSFP+ LC Transceivers, What are the Differences?

Support Different Bandwidth and Speed

 

The 40G QSFP+ MTP transceiver features a high-density MTP interface that allows multiple channels to be utilized simultaneously to handle higher bandwidth. This design is suitable for environments that require robust data rates and fast speeds, making it ideal for high-demand environments such as data centers. 

 

On the other hand, 40G QSFP+ LC transceivers with LC interfaces are compatible with existing LC fiber infrastructures, providing a cost-effective solution for networks operating within these infrastructures. However, its bandwidth may be limited compared to MTP transceivers. To make an informed choice between these transceivers, prioritizing speed, scalability, and existing infrastructure requirements within the network architecture is essential.

Designed with Different Working Principles

 

The 40G QSFP+ MTP transceiver efficiently converts electrical signals to optical signals through a laser array, facilitating simultaneous data transmission across multiple channels. Utilizing MTP parallel cables ensures seamless transmission, complemented by photodetectors at the receiving end for signal conversion. Its standout feature is the MTP interface, which allows external 12-fiber parallel-to-duplex breakout cables and supports 4x10G connections. This design grants the transceiver adaptability in handling parallel data, offering versatile connectivity and scalability for diverse transmission needs in network architectures.

 

The 40G QSFP+ LC transceiver transfers four channels of 10G serial data streams to a laser driver, controlling directly modulated lasers (DML). These four DML outputs merge via LC connectors into a 40G optical signal transmitted through single-mode fibers. At the receiving end, the signal is split into four different 10G channels based on wavelength, collected by photodiodes (PIN), and converted to electronic data via trans-impedance amplifiers (TIA). Unlike the MTP interface, this LC interface operates on four wavelengths through single-mode fibers, lacking the capability for four independent 10G paths. This operational method limits connectivity and routing options, potentially making the LC interface less versatile for specific transmission needs and network architectures when compared to the MTP interface transceiver.

Cabling with Different Fiber Type 

 

Since 40G MTP optical modules and 40G LC optical modules use different connectors, different fiber types are applied to them. To ensure optimal network performance in day-ahead operations, using the appropriate fiber connection for each module is crucial.

 

The 40G QSFP+ MTP transceiver is ideal for short-distance transmission over multimode fiber. It offers two connection options: a backbone cable with MTP connectors for 40G-40G links, and a harness cable equipped with an MTP connector on one end and four LC duplex connectors on the other, designed for 40G-4x10G connections.

Conversely, the 40G QSFP+ typically operates over single-mode fiber (SMF) for long-haul 40G-40G network transmissions. Variants like 40GBASE-LR4/LR4L/ER4 utilize single-mode LC duplex patch cords, while the LC-interfaced 40GBASE-UNIV supports both SMF and MMF LC patch cords.

QSFP+ MTP vs QSFP+ LC Transceivers, How to Choose?

Wiring Requirement: High Density or Flexible Connection?

QSFP+ MTP transceivers stand out in high-density environments due to their MTP/MPO connectors, enabling multiple fibers within a single connection. This design proves ideal where limited space and streamlined cable management are essential. Conversely, QSFP+ LC transceivers offer connectivity flexibility using LC connectors compatible with diverse setups and systems. This versatility caters to networks requiring adaptable connections across moderate distances.

Consider Compatibility and Integration with Various Devices

QSFP+ MTP transceivers deliver high performance in scenarios requiring multiple fibers within a single connection, especially when paired with specific switches and hardware optimized for MTP connectivity. In contrast, QSFP+ LC transceivers, utilizing LC connectors, boast extensive compatibility across various devices and systems. Their ability to adapt to multiple switches and devices makes them a more versatile option for networks seeking compatibility with different hardware setups.

Basic Performance Parameters Evaluation

Evaluating parameters such as transmission speed, reach, power consumption, and compatibility with the network environment becomes pivotal in selecting the appropriate transceiver. Factors like scalability, cost-effectiveness, and ease of deployment also weigh heavily in this decision-making process, ensuring a seamless integration of transceivers tailored to the specific requirements of the network infrastructure.

Cost and Future Scalability Consideration

Factor in both upfront costs and long-term scalability. MTP connectors might have a higher initial cost due to high-density capabilities but could be cost-effective for setups requiring many connections in the future. LC connectors might be more budget-friendly for smaller-scale needs but may limit scalability.

FAQs：

Q: Can both  40G QSFP+ MTP and 40G QSFP+ LC transceiver used for a 4×10G solution？

A: The answer is no. Typically, 40G QSFP+ MTP can be used for a 4×10G connection via breakout fiber cables. In contrast, the LC-based transceivers can't be divided into 4x10G since they use four wavelengths on one pair of SMF.

 

Q: Can 40G QSFP+ MTP and 40G QSFP+ LC transceivers work on the same network?

A: Yes, 40G QSFP+ MTP and 40G QSFP+ LC transceivers can work in the same network. Both transceivers operate at 40Gbps and are designed to meet specific connectivity requirements.

 

Q: Are there noticeable performance differences, such as latency or bandwidth, between 40G QSFP+ MTP and 40G QSFP+ LC transceivers?

A: No, there are no noticeable performance differences in latency or bandwidth between 40G QSFP+ transceivers with MTP and LC connectors.

 

Q: What's the difference between an MTP and an MPO connector?

A: MPO is an older and more generic term for multi-fiber connectors, whereas MTP is a specific type of MPO connector developed by US Conec, known for its improved performance and precision.

 

Q: Which type is preferred by users, the MTP Transceiver or the LC Transceiver?

A: The choice between MTP and LC transceivers often depends on the network's specific needs.

Conclusion

 

Understanding their differences is crucial to choosing between 40G QSFP+ MTP and LC transceivers. MTP-based transceivers shine in high-density environments, offering streamlined cable management and superior bandwidth for short distances, like within data centers. Conversely, LC transceivers, utilizing LC connectors, cater to medium distances and seamlessly integrate with existing systems, providing adaptability across diverse setups. Ultimately, the decision depends on specific network performance needs, guiding the selection between these two interface options; for any inquiries, feel free to contact us via [email protected].