Tag Archives: 40GBASE-LR4

Transceiver Solutions for Migrating to 40G Ethernet

As the need for increased network bandwidth to meet the global IP traffic demand is growing rapidly, there is an urgent need for upgrading to 40G Ethernet links in data centers. And the IEEE 802.3ba committee has already ratified the 40G Ethernet standard and along with the general specification, defining a number of fiber optic interfaces. These standard interfaces attempted to satisfy a number of different objectives including support for multi-mode fiber (MMF) and single mode fiber (SMF) compatibility. Therefore, there appears various transceiver solutions for migrating to 40G Ethernet network. Among these solutions, there are three popular ones: 40Gbase LR4 QSFP+ transceiver, 40Gbase SR4 QSFP+ transceiver and 40G QSFP BiDi transceiver. This article will give a comprehensive comparison on them.

40GBASE LR4 QSFP+ Transceiver

40G LR4 QSFP+ transceivers are hot-swappable Ethernet optical transceivers that support high-speed serial links over single mode optical fiber. With built-in optical multiplexing and de-multiplexing, this kind of transceiver has four channels of 10G multiplexed/de-multiplexed inside the module to transmit and receive an aggregate 40G signal over a single pair (2 strands) of fiber. Used with LC connectors and single mode fiber, 40G LR4 QSFP+ transceivers’ transmission distance can cover around 10km.

As 40G LR4 QSFP+ transceivers can be used together with LC connectors, they may use existing duplex fiber infrastructure for 40G migration. That’s to say, 40G LR4 QSFP+ transceivers can offer a very cost effective connectivity solution and unique value proposition for data centers to migrate from 10G to 40G Ethernet network with minimal disruption with existing fiber optical infrastructure. The main disadvantage of 40G LR4 QSFP+ transceivers is that the optical link may not be as simple as that of 40G LR4 QSFP+ transceivers. The following is a picture of Finisar FTL4C1QE1C compatible 40GBASE-LR4 QSFP+ transceiver.

40GBASE-LR4 QSFP for 40G ethernet

40GBASE SR4 QSFP+ Transceiver

40G SR4 QSFP+ transceivers are parallel fiber optical module with four independent optical transmit and receive channels. Each of these channels is capable of a 10G operation for an aggregate data rate of 40G. These transceivers use MTP/MPO connectors and require multi-mode OM3 or OM4 cables. They can support with a link length up to 100 meters on OM3 cable and 150 meters on OM4 cable.

40G SR4 QSFP+ transceivers use fundamentally different connectivity formats, requiring fiber cabling infrastructure to be redesigned and replaced. Thus, they cannot reuse aggregation fiber infrastructure built for 10-Gbps connectivity. The following is a picture of Cisco QSFP-40G-SR4 compatible 40GBASE-SR4 QSFP+ transceiver.

Cisco QSFP-40G-SR4 Compatible 40GBASE-SR4 QSFP+ Transceiver

40G QSFP BiDi Transceiver

40G QSFP BiDi transceivers are the lasted products used in 40G transmission. They are transceivers that transmit full-duplex 40-Gbps traffic over one dual-fiber LC-connector OM3 or OM4 MMF cable. 40G QSFP BiDi transceivers have two 20Gbps channels, each transmitted and received simultaneously over two wavelengths on a single MMF strand. The result is an aggregated duplex 40Gbps link over a MMF duplex LC-terminated fiber cable. The connection can reach 100 meters on OM3 MMF or 150 meters on OM4 MMF, which is the same as 40Gbps SR4. The following figure shows the technology concept of the Cisco QSFP BiDi transceiver.

QSFP BiDi transceiver

To accommodate an ever increasing spectrum of 40G Ethernet applications, Fiberstore offers various 40GBASE QSFP+ transceiver types, suitable for different media and distance reaches. All of our QSFP+ transceivers are tested in-house prior to shipping to ensure that they will arrive in perfect physical and working condition. We offer our customers with high-performance and cost-effective products to fulfill their requirements, contributing this way to the customer’s success and satisfaction.

Cisco 40GBASE QSFP+ Modules

Cisco QSFP (quad small form-factor pluggable plus) modules offer customers a wide variety of high-density and low-power 40 Gigabit Ethernet connectivity options for data center, high-performance computing networks, enterprise core and distribution layers, and service provider transport applications. In this post, several different kinds of connectivity options provided by Cisco will be introduced.

Features and Benefits of Cisco QSFP Module

Main features of Cisco QSFP modules include:

  • Interoperable with other IEEE-compliant 40GBASE interfaces
  • Hot-swappable input/output device that plugs into a 40 Gigabit Ethernet QSFP+ Cisco switch port
  • High-speed electrical interface compliant to the IEEE 802.3ba standard
  • Compliant to SFF 8436 and QSFP Multisource Agreement (MSA)
Cisco QSFP-40G-SR4-S

Cisco 40GBASE-SR4 QSFP+ module supports link lengths of 100m and 150m respectively on laseroptimized OM3 and OM4 multimode fiber cables. It primarily enables high-bandwidth 40G optical links over 12-fiber ribbon r cables terminated with MPO/MTP multi-fiber connectors. It can also be used in 4x10G mode along with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR optical interfaces. Cisco QSFP-40G-SR4-S is optimized to guarantee interoperability with any IEEE-compliant 40GBase-SR4 module.

Cisco QSFP-40G-CSR4

Cisco 40GBASE-CSR4 QSFP+ module extends the reach of the IEEE 40GBASE-SR4 interface to 300m and 400m respectively on laser-optimized OM3 and OM4 multimode fiber cables. Each 10-gigabit lane of this module is compliant to IEEE 10GBASE-SR specifications. This module can be used for native 40G optical links over 12-fiber ribbon cables with MPO/MTP connectors, or in a 4x10G mode with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR interfaces. The following picture shows a Cisco QSFP-40G-SR4-S QSFP+ module and a Cisco QSFP-40G-CSR4 QSFP+ module.

cisco qsfp

Cisco QSFP-40G-LR4-S

Cisco 40GBASE-LR4 QSFP module supports link lengths of up to 10 km over a standard pair of G.652 single-mode fiber with duplex LC connectors. QSFP-40G-LR4-S module supports 40GBase Ethernet rate only. 40 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed in the device. QSFP-40G-LR4-S does not support FCoE.

Cisco WSP-Q40GLR4L

Cisco WSP-Q40GLR4L QSFP+ module supports link lengths of up to 2 km over a standard pair of G.652 single-mode fiber (SMF) with duplex LC connectors. 40 Gigabit Ethernet signal is carried over four wavelengths. It is interoperable with 40GBase-LR4 for distances up to 2 kilometers. The following picture shows a Cisco QSFP-40G-LR4-S QSFP+ module and a Cisco WSP-Q40GLR4L QSFP+ module.

QSFP-40G-LR4-S QSFP+ and WSP-Q40GLR4L QSFP+

Cisco QSFP Copper Direct Attach Cables (DACs)

Cisco QSFP+ cable include QSFP+ to QSFP+ copper DACs and QSFP+ to 4SFP+ copper DACs. Cisco QSFP+ cables are suitable for very short distances and offer a very cost-effective way to establish a 40-gigabit link between QSFP+ ports of Cisco switches within racks and across adjacent racks. QSFP+ to 4SFP+ copper breakout DACs cables connect to a 40G QSFP+ port of a Cisco switch on one end and to four 10G SFP+ ports of a Cisco switch on the other end.

Cisco QSFP Active Optical Cables (AOCs)

Cisco 40g AOCs include QSFP+ to QSFP+ AOCs and QSFP+ to 4SFP+ AOCs. Active optical cables are much thinner and lighter than copper cables, which makes cabling easier. Active optical cables enable efficient system airflow and have no electromagnetic interference (EMI) issues, which is critical in high-density racks.

Fiberstore is a professional manufacturer and supplier for optical fiber products and provides various kinds of 40GBase QSFP+ transceivers branded by many famous companies. Cisco 40g transceivers offered by Fiberstore are the most cost-effective standards-based QSFP+ modules fully compatible with Cisco switches and routers. They are 100% compatible with major brands and backed by a lifetime warranty.