There is a growing need in the data center for upgrading from 10G to 40G switch connections due to server consolidation, virtualization, and performance improvements. However, for many data center operators this upgrade and conversion is more challenging based on two primary factors. First, the potential for a reconfiguration of the physical layer of the network based on the reduced reach of the OM3/OM4 multimode optics from 10GBASE-SR (300/400 m) to 40GBASE-SR4 (100/150 m) and second, the existing fiber optic cabling plant may need to be upgraded based on the additional fiber count needed to support the IEEE-defined 40GBASE-SR4 parallel optics. These two factors bring the SMF&MMF 40G QSFP+ transceiver to market.

What Is SMF&MMF 40G QSFP+ Transceiver?

As we all know, a fiber optic transceiver may either operate on multimode fiber (MMF) or single-mode fiber (SMF). However, a SMF&MMF 40G QSFP+ transceiver can be used with both MMF and SMF without the need for any software/hardware changes to the transceiver module or any additional hardware in the network. Usually, this transceiver is based on IEEE defined 40GBASE-LR4 specifications and operates in the 1310 nm band. It uses a duplex LC connector and supports distances up to 150 m over OM3 or OM4 multimode fiber and up to 500 m over single-mode fiber (different vendor may have different specifications). This is usually accomplished by combining four 10G optical channels at different wavelengths (1270, 1290, 1310, and 1330 nm) inside the transceiver module to transmit and receive an aggregate 40G signal over a single pair of multimode or single-mode fibers.

Advantages of SMF&MMF 40G QSFP+ Transceiver

With the increase in data center bandwidth requirements, migration to 40G for switch to switch connections is in higher demand. SMF&MMF 40G QSFP+ transceiver is designed to allow for seamless migrations from existing 10 to 40GbE networking without requiring a redesign or expansion of the fiber network. Besides, this transceiver also provides a cost-effective solution to migrate from multimode to single-mode fiber, allows a single-mode fiber infrastructure for distances up to 500m. The advantages of SMF&MMF 40G QSFP+ are as following.

Cabling Migrating from 10G to 40G

Existing 40G transceivers for short reach, QSFP+ SR4 and the extended reach QSFP+ CSR4, utilize four independent 10G transmitters and receivers for an aggregate 40G link, which use an MPO-12 connector and require 8-fiber parallel multimode fiber (OM3 or OM4). However, a SMF&MMF QSFP+ uses duplex LC connector, which is consistent with the existing 10G connections, which are also commonly MMF cables with duplex LC connectors. Therefore, a SMF&MMF QSFP+ allows the same cables to be used for direct 10G connections to direct 40G connections, resulting in zero-cost cabling migration.

Increase Number of 40G Links in the Network

As existing MMF 40G solutions need the use of 8 fibers for a 40G link, customers have to add additional fiber to increase the number of 40G links. By deploying the SMF&MMF 40G QSFP+ transceiver, customers increase the number of 40G links by 4 times without making any changes to their fiber infrastructure, which greatly expand network scale and performance.

Migrate from Multimode to Single-mode Fiber

As data rates increase from 40G to 100G and beyond to 400G, there is a strong desire for data centers to move to single-mode fiber for cost effectiveness. Due to the limitations of multimode transceivers to support existing distances with ever increasing data rates, migrating to 100G and 400G in the future will be simpler with single-mode fiber. However, the single-mode transceivers typically cost up to 4 times more compared to multimode transceivers. As SMF&MMF QSFP+ interoperates with 10km QSFP-LR4 optics, it is a cost effective solution for SM fiber infrastructure for distances up to 500m.

Simplify the Data Centers with a Mix of MMF and SMF Deployments

The SMF&MMF 40G QSFP+ transceiver offers the unique advantage of operating on both multimode and single-mode fiber without any requirement for additional hardware or software. Customers can consolidate their optics and use SMF&MMF QSFP +in their network irrespective of the fiber type, which makes full use of the existing cabling systems, reduces the cost of deployment and of support, and simplify purchasing and deployments.

Conclusion

The SMF&MMF 40G QSFP+ transceiver enables data centers running at 10G today to seamlessly upgrade to 40G without having to re-design or modify the cable infrastructure, which allows organizations to migrate their existing 10G infrastructure to 40G at zero cost of fiber and to expand the infrastructure with low capital investment. It also offers a transition path for customer planning migrations to single-mode fiber in data centers with a single transceiver that bridges the gap between multi-mode and single-mode optics. Wiitek SMF&MMF 40G QSFP+ transceiver provides a cost-effective solution for migrating to next-generation 40G data center deployments.