SMF&MMF 40G QSFP+ Transceiver Overview

The demand for better network throughput and performance has never ceased. Instead, it has become more and more vigorous. The server consolidation, virtualization, as well as networking-service performance improvements, all these have pushed the necessity for dense 40GbE switch connections in data centers.
But when migrating to 40GbE from10GbE, some companies or organizations are challenged by two main factors in re-configuring the physical layer of the network: firstly, the possible reduced reach of the OM3/OM4 multi-mode optics from 10GBASE-SR (300/400 m) to 40GBASE-SR4 (100/150m), and secondly, the need to upgrade the existing fiber optic cabling plant so as to support the IEEE-defined 40GBASE-SR4 parallel optics. In order to avoid these questions, SMF&MMF 40G QSFP+ transceiver is brought to the market.
SMF&MMF 40G QSFP+ Transceiver Definition
It’s know that a fiber optic transceiver may either operate on single-mode fiber (SMF) or multi-mode fiber (MMF). However, this SMF&MMF 40G QSFP+ transceiver is able to communicate with both SMF and MMF, without the need for any software/hardware changes to the transceiver module or any additional hardware in the network. It has 4 channels (1270, 1290,1310, and 1330nm) of 10G multiplexed inside the module to transmit and receive an aggregate 40G signal over 2 strands of fiber with a duplex LC connector.
Based on IEEE defined 40GBASE-LR4 specifications, this supports distances up to 150m over OM3 or OM4 MMF and up to 500m over SMF. Certainly, different fiber optic equipment vendors may have different specifications.
SMF&MMF 40G QSFP+ Transceiver Advantages
SMF&MMF 40G QSFP+ transceiver is designed for seamless migrations from existing 10GbE to 40GbE networking without modification or expansion of the fiber network. It addresses several challenges faced by today’s data centers and the passages highlight the advantages of this transceiver.
No Redesign or Expansion of Fiber Network
Other short-reach 40G QSFP+ transceiver types, such as MMF 40GBASE-SR4 transceivers (100m over OM3 MMF), utilize four independent 10G transmitters and receivers for an aggregate 40G link. These 40GBASE-SR4 transceivers (eg. JG325B) use a MPO-12 connector and require 8-fiber parallel OM3 or OM4. As a result, customers installing MTP/MPO fiber systems may need to deploy new fiber while upgrading from 10G to 40G. However, SMF&MMF 40G QSFP+ transceiver uses duplex LC connector, which is consistent with the existing 10G connections. It works on existing OM3 and OM4 MMF infrastructure which is widely installed and used for 10GbE networks, thus free from redesign or expansion of the fiber network.
Increase in the Number of 40G Links
The existing MMF 40GbE solutions use of 8 fibers for a 40G link, and customers have to add additional fiber if they want to increase the number of 40G links. But if you deploy SMF&MMF 40G QSFP+ transceiver, the number of 40G links is 4our times of that existing MMF 40GbE solutions without any changes to their fiber infrastructure. During this link increase, the network scale and performance are also expanded.
A Cost-effective Solution for SMF Infrastructure
Limited in the distance reach that multi-mode transceivers can support, the migration from 10G to 40G, to 100G, or even 400G would become simpler with SMF. But single-mode transceivers typically cost up to 4 times more compared to multi-mode transceivers. Since SMF&MMF QSFP+ transceiver interoperates with QSFP-LR4 and QSFP-LR4L optics, it’s a cost effective solution for SM fiber infrastructure for distances up to 500m. And customers can deploy mixed connections without fiber concerns.
Simplification in Infrastructure Deployment
SMF&MMF QSFP+ transceiver boasts of the unique characteristic of working through both SMF and MMF without any requirement for additional fiber. Customers can consolidate their optics and use SMF&MMF QSFP+ transceiver in their network without concern about the fiber type, which makes the full use of existing cabling infrastructure, leading to the reduced equipment cost and simplification of deployment.

 

Introduction of 40 Gigabit QSFP+ Transceiver

by http://www.fiber-mart.com

QSFP+ (Quad Small Form-factor Pluggable Plus) transceiver interfaces a network device motherboard (for a switch, router, media converter or similar device) to a fiber optic cable, which is widely used for data communications applications. It is a industry format jointly developed and supported by many network component vendors. QSFP+ is also the IEEE standard connector for the emerging 40GbE standard. QSFP+ modules increase the port-density by nearly 3 times when compared to SFP+ module.
Overview on 40G QSFP+ Transceiver
40G QSFP+ transceivers are designed to support Serial Attached SCSI, 40G Ethernet, 20G/40G Infiniband, and other communications standards. The 40G QSFP+ modules are favorable for high density 40G optical network. These modules are designed to operate over single-mode or multimode fiber systems with differently optimized lasers under different standards. 40G QSFP+ transceiver interface can be either duplex LC or 12-fiber MTP/MPO as shown in the following picture. The 40G QSFP+ transceiver module with MTP/MPO interface is a hot-swappable, parallel fiber-optical module with 4 independent 10 gigabit per second data lanes in each direction to provide 40Gbps aggregate bandwidth. 40G QSFP+ modules offer customers a wide variety of high-density 40 gigabit Ethernet connectivity options for data center, high-performance computing networks, enterprise core and distribution layers, and service provider transport applications.
Application of Different 40G QSFP+ Transceivers
The transceiver is used primarily in short reach applications in switches, routers, and data center equipment where it provides higher density than SFP+ modules. With the evolving of the format specification, now in the market, you can find a wide varieties of 40G QSFP+ transceivers including the short distance types, Bidi, and long distance types, of which 40GBASE-SR4 (QSFP-40G-SR4), 40GBASE-LR4 (QSFP-40G-LR4) and 40GBASE-ER4 (QSFP-40G-ER4) are the most commonly used physical layers for 40G QSFP+ modules.
QSFP-40G-SR4 (short range) transceiver has a port type for multimode fiber and uses 850nm lasers. It supports link lengths of 100 m and 150 m respectively on laser-optimized OM3 and OM4 multimode fiber cables. It is commonly used in data centers to interconnect two Ethernet switches with 12 lane ribbon OM3/OM4 cables. Primarily it enables high-bandwidth 40G optical links over ribbon fiber cables terminated with multi-fiber connectors (MTP/MPO), and could also be used along with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR optical interfaces.
QSFP-40G-LR4 (long range)or QSFP-40G-ER4 (extended range) transceiver has a port type for single-mode fiber and uses 1300nm region lasers. It uses two strands of fiber and combines four wavelengths by CWDM technology, delivering serialized data at a rate of 10Gbit/s per wavelength. Thus the optical interface can be simplified to standard LC connectors. QSFP-40G-LR4 transceiver is most commonly deployed between data canters or for IXP (Internet exchange point) site.
Conclusion
The QSFP+ transceiver is a great solution for multi-lane data communication and interconnect applications. fiber-mart.COM offers the best 40G QSFP+ modules. All these 40G QSFP+ modules are Cisco, Juniper, IBM and HP compatible. In addition to 40Gbps Ethernet interconnects, it can be used in datacom/telecom switch, and router connections, as well as data aggregation and backplane applications. Also you can have a wide selection of other transceivers and direct attached cables at fiber-mart.COM, including XFP transceivers, SFP transceivers, CFP modules, copper DAC, active optical cable and so on.