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Things to Know about 40GBASE-SR4 QSFP+ Modules

With the growing demand for high data rates, 40 Gigabit Ethernet (GbE) is now becoming more and more widely adopted. For a 40 GbE network application, precise connectivity is crucial. 40G QSFP (quad small form factor pluggable) portfolio offers customers a wide variety of high-density and low-power 40 Gigabit Ethernet connectivity options. Among them, 40GBASE-SR4 QSFP+ transceiver is a common 40 GbE connectivity option. And here are some things that you need to know about 40GBASE-SR4 QSFP+ transceivers.

Introduction

40GBASE-SR4 is a fiber optic interface for multimode fiber of OM classes 3 and 4 with four parallel OM3 or OM4 fibers in both directions. “S” means short, indicating that it is an interface for short distances. The “R” denotes the type of interface with 64B/66B encoding and the numeral 4 indicates that the transmission is carried out over a ribbon fiber with four multimode fibers in every direction. Each lane has a 10 Gbit/s data rate. 40GBASE-SR4 QSFP+ modules usually use a parallel multimode fiber (MMF) link to achieve 40G. It offers 4 independent transmit and receive channels, each capable of 10G operation for an aggregate data rate of 40G over 100 meters of OM3 MMF or 150 meters of OM4 MMF. It primarily enables high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multifiber female connectors.

40GBASE-SR4 QSFP+ module can also be used in a 4x10G mode for interoperability with 10GBASE-SR interfaces up to 100 and 150 meters on OM3 and OM4 fibers, respectively. The worry-free 4x10G mode operation is enabled by the optimization of the transmit and receive optical characteristics to prevent receiver overload or unnecessary triggering of alarm thresholds on the 10GBASE-SR receiver, and at the same time is completely interoperable with all standard 40GBASE-SR4 interfaces. The 4x10G connectivity is achieved using an external 12-fiber parallel to 2-fiber duplex breakout cable, which connects the 40GBASE-SR4 module to four 10GBASE-SR optical interfaces. The picture below shows a Mellanox MC2210411-SR4 compatible 40GBASE-SR4 QSFP+ transceiver.

Mellanox MC2210411-SR4 Compatible 40GBASE-SR4 QSFP+ Transceiver

40GBASE-SR4 QSFP+ Module vs 40GBASE-CSR4 QSFP+ Module

40GBASE-CSR4 QSFP+ module is similar to the 40GBASE-SR4 interface extends supported link lengths 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 4x10G mode with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR interfaces. Maximum channel insertion loss allowed is respectively 2.6dB over 300m of OM3 cable or 2.9dB over 400m of OM4 cable.

Conclusion

Fiberstore offers you a wide variety of 40GBASE-SR4 QSFP+ transceivers for your high-density and low-power 40 Gigabit Ethernet connectivity options branded by many famous companies like Cisco, Juniper or HP. And we also provide other compatible 40G QSFP+ transceivers, such as 40GBASE-LR4 QSFP+ transceiver, 40GBASE-ER4 QSFP+ transceiver, 40GBASE-CSR4 QSFP+ transceiver, etc. Every fiber optic transceiver provided by Fiberstore has been tested to ensure its compatibility and interoperability. You can buy from us with confidence.

Parallel Optics Technology Overview

The number of network connections in data centers is on the rise. Data centers have to achieve ultra-high density in cabling. Multimode fiber optics is the medium of the future for satisfying the growing need for transmission speed and data volume over short distances. Parallel optics technology is what you get if you combine both trends—cabling density and the use of fiber optics. It is a suitable solution for high-performance data networks in data centers. This passage provides introductory information on parallel optics technology.

What Is Parallel Optics?

Parallel optics is a term used to represent both a type of optical communication and the devices on either end of the link that transmit and receive information. It differs from traditional fiber optic communication in that data is simultaneously transmitted and received over multiple optical fibers. In parallel optical communication, the devices on either end of the link contain multiple transmitters and receivers. For example, four transmitters on End A communicate with four receivers on End B, spreading a single stream of data over four optical fibers. With this configuration, a parallel optics transceiver can use four 2.5Gb/s transmitters to send one 10Gb/s signal from A to B.

Parallel optical devices are fundamentally different in construction from serial optical devices. Two complementary technologies have enabled the development and deployment of parallel optics devices: vertical cavity surface emission lasers (VCSELs) and the MPO connector. Parallel optic transmission technology spatially multiplexes or divides a high-data-rate signal among several fibers that are simultaneously transmitted and received. At the receiver, the signals are de-multiplexed to the original high-data-rate signal. MPO connectivity is used throughout the parallel optic link and interfaces into the transceiver module. An MPO connector and its connectivity method is showed in the picture below (Tx stands for transmit, Rx stands for receive).

12-fiber-MTP-parallel-connection-1024x366

Applications of Parallel Optics Technology

Parallel optic interfaces (POIs) are a fiber optic technology primarily targeted for short-reach multimode fiber systems (less than 300 meters) that operate at high data rates. Duplex fiber serial transmission with a directly modulated 850 nm VCSEL has been used to date for data rates up to 10G. Current and future protocols expected to use parallel optics include 40G and 100G Ethernet, InfiniBand and Fibre Channel speeds of 32G and higher. IEEE has already included physical layer specifications and management parameters for 40Gbps and 100Gbps operation over fiber optic cable. The uses of parallel optics technology continues to evolve and takes shape as higher-speed fiber optic transmission. Many cabling and network experts have pointed out that parallel optical communication supported with MPO technology is currently a way to equip an environment well prepared for the 40/100GbE transmission.

Why Choose Parallel Optics?

Parallel optical communication uses multiple paths to transmit a signal at a greater data rate than the individual electronics can support. Parallel transmission can either lower the cost of a given data rate (by using slower, less expensive optoelectronics) or enable data rates that are unattainable with traditional serial transmission. Moreover, POIs offer an economical solution that utilizes multimode fiber, which is optimized with VSCEL sources. This means that for speeds faster then 16G, parallel optics, is the most practical, cost-effective solution.

Parallel optics is one technology currently on the market for high data rates networking solutions. Fiberstore is a professional manufacturer and supplier, which offers a large amount of cables and transceivers for your parallel optics applications, such as QSFP+ transceiver and QSFP+ cable. Parallel optical transceivers used for 40GBASE-SR4 and 40GBASE-CSR4 have 10-Gbps electrical lanes that are mirrored in the optical outputs.

The Basics of Push-Pull Patch Cables

During cabling and daily maintenance, it is inevitable to plug fiber optic connectors in or pull them out from switches. But finger access to each patch cable and connector is very difficult in a high density cabling system. For patch cords with connectors like LC that are locked in the interface, it would be even more difficult, for you have to unlock the connector from the port first before pull it out. To solve this problem, a simple and easy solution for high density cable management is introduced, which is push-pull patch cable. This article will give you a brief introduction to it.

What Is Push-Pull Patch Cable?

A push-pull patch cable, or push-pull patch cord, has the same components and internal-structure as the traditional patch cords, except a tab attached to the connector used for pushing or pulling the whole connector, so it is also called push-pull tab patch cord. This small push-pull tab looks simple but it is functional for high density cabling in 40/100G migration. High density cabling for 40G/100G and beyond usually employs MPO and LC connectors. The image below shows push-pull patch cables with LC or MPO connectors.

push-pull-tab-patch-cords_

Two Types of Push-Pull Patch Cable

As mentioned above, MPO and LC connectors are two commonly used connector types for push-pull patch cables. At this part, push-pull tab LC patch cord and push-pull tab MPO patch cable will be introduced.

Push-Pull LC Patch Cord: Push-pull LC patch cord contains the custom push-pull strain relief boot, and allows users easy accessibility when deploying very high density LC patch fields in data center applications. Push-pull tab LC cables are available in riser (OFNR), and low smoke zero halogen (LSZH) rated jacket materials to comply with local cabling ordinances and OM4, OM3 or OS1/OS2 fiber types to meet the demands of today’s highest speed applications. They provide interconnect and cross-connect of applications in entrance facilities, telecommunication rooms, data centers, at the desk and network applications to interconnect pre-terminated cassettes in main distribution, horizontal distribution, and equipment distribution areas.

Push-Pull MPO Patch Cable: Push-pull tab MPO patch cable allows high-density connections between network equipment in telecommunication rooms. They feature push-pull tab connectors that offer maximum accessibility in high density installations. You can install or remove it with one hand, providing quick fiber optic connections. The MTP/MPO connector is approximately the same size of a SC connector and it can accommodate 24 fibers, so it provides up to 24 times the density of SC style connectors, thereby offering savings in circuit card and rack space. High-density design cuts down on installation costs. And there is no need for long fan-out cables or individual long duplex cable runs.

Applications and Advantages

Push-pull patch cables offer ease of installation as well as superior performance. Other advantages include easy to remove, reducing risk of failure, and space saving. They utilize the latest engineered polymers, precision ceramics, and the finest metals to address specific applications, enabling a wide range of cable choices, SMF or MMF. They are highly recommended in interconnect systems. The table below shows their applications in details.

Push-pull patch cable applications

Push-pull tab patch cords can support high durability and flexibility which fit the connection between devices of different data rate. Fiberstore offers a full range of push-pull patch cables for your network applications. You can always buy from us with confidence.

40 GbE and 100 GbE over Multimode Fiber

To support the changing and fast-growing bandwidth demands of data centers, the IEEE ratified standards for supporting 40 GbE (Gigabit Ethernet) and 100 GbE (Gigabit Ethernet), known as IEEE 802.3ba. Both 40 and 100 GbE can be deployed using the same cabling systems in use today. Multimode will employ parallel optics using MPO interconnects and require additional cable infrastructure depending on the system deployed while single mode fiber will employ serial transmission and use LC or SC connectors. Each has its own advantages and disadvantages. In this post, 40 GbE and 100 GbE over multimode fiber will be introduced.

40 GbE and 100 GbE Standard

IEEE published the IEEE 802.3ba standard for 40 Gigabit and 100 Gigabit Ethernet in June 2010. multimode optical fiber OM1, OM2, OM3 and OM4 have different capabilities of supporting different Ethernet applications. Only the laser optimized multimode fiber (grades OM3 and OM4) are capable of supporting 40G and 100G Ethernet. The next part will focus on the cabling requirements of 40 GbE and 100 GbE over multimode fiber. The table below shows 40GE and 100GE specifications.

40 GbE and 100 GbE Specifications

Implementing Parallel Optics

Traditionally, the Ethernet standard has relied upon duplex fiber cabling with each channel using one fiber to transmit and the other to receive. However, the 802.3ab standard requires multiple lanes of traffic per channel. To do this, the 40/100GbE standard uses parallel optics. The 802.3ba standard defines the parallel operation of four OM3/OM4 fibers for 40 GbE in 40GBASE-SR4 and the parallel operation of ten OM3/OM4 fibers for 100 GbE in 100GBASESR10. Two fibers have to be used per link because this arrangement is full duplex operation, i.e. simultaneous transmission in both directions. Therefore the number of fibers increases to eight for 40GBASE-SR4 and to 20 for 100GBASE-SR10. In the parallel optical link, the signal is split, transmitted over separate fibers and then joined again. That means the individual signals have to arrive at the receiver at the same time. Any skew in signal components has to be kept within tight tolerances. Trunk cables preterminated with MPO/MTP connectors are therefore the best choice for reliable transmission.

What Is 40 GbE and 100GbE over Multimode Fiber?

40G Ethernet and 100G Ethernet over multimode fiber uses parallel optics at 10 Gb/s per lane. One lane uses 1 fiber for each direction of transmission. 40G Ethernet requires 8 fibers. 100G Ethernet requires 20 fibers. The minimum performance that is needed to support 40 GbE and 100 GbE over multimode fiber is OM3 fiber for a distance of 100 meters. Cabling with OM4 fiber provides the capability to extend the reach up to 150 meters. Parallel optical channels with multi-fiber multimode optical fibers of the categories OM3 and OM4 are used for implementing 40 GbE and 100 GbE. The small diameter of the optical fibers poses no problems in laying the lines, and 802.3ba standard incorporated the MPO multi-fiber connector for 40GBASE-SR4 and 100GBASE-SR10, which can contact 12 or 24 fibers in the tiniest of spaces.

Conclusion

Optical fiber cabling is commonly deployed for backbone cabling in data centers for switch to switch connections and also for horizontal cabling for switch to server and storage area network connections. The use of pre-terminated optical fiber cabling can facilitate the migration path to 40G and 100G Ethernet in the future. Fiberstore can supply you with top-quality components for your 40 GbE and 100 GbE network, like 40G QSFP transceivers, and all kinds of QSFP+ cable choices, it also assists you competently with all questions involving planning, installation and maintenance.

Introduction to MPO/MTP Technology in 40 GbE

The increasing demands of bandwidth and high speed drive the emergence of 40 GbE, and even up to higher in the future. And the high-speed transmission requires high-density data center as the increasing created data need amount of cables and devices which take a lot of space and cost. Data centers have to achieve ultra-high density in cabling to accommodate all this cabling in the first place. Multimode fiber optics is the medium of the future for satisfying the growing need for transmission speed and data volume over short distances. Ultra-parallel connections involve tougher requirements in terms of the components and the handling of the connectors. The MPO/MTP technology has proven to be a practical solution. This article provides introductory information on MPO/MTP technology in 40 GbE.

MPO/MTP—Multi-fiber Connectors for High Port Density

Parallel optical channels with multi-fiber multimode optical fibers of the categories OM3 and OM4 are used for implementing 40 GbE. The small diameter of the optical fibers poses no problems in laying the lines, but the ports suddenly have to accommodate four or even ten times the number of connectors. This large number of connectors can no longer be covered with conventional individual connectors. That is why the 802.3ba standard incorporated the MPO multi-fiber connector for 40GBASE-SR4. It can contact 12 or 24 fibers in the tiniest of spaces. Next part describes this type of connector.

12 Fibers 10G OM4 Harness Cable, 12 Strands, MPO-HD to LC-HD Push Pull TAB Connector

MPO Connectors: Structure and Function

The MPO connector (known as multi-fiber push-on and also as multi-path push-on) is a multi-fiber connector defined according to IEC 61754-7 and TIA/EIA 604-5 that can accommodate up to 72 fibers in the tiniest of spaces, comparable to an RJ45 connector. MPO connectors are most commonly used for 12 or 24 fibers. Eight fibers are needed for 40 GbE, which means four contacts remain non-interconnected in each case. MPO connectors and MTP (mechanical transfer push-on) connectors are no longer terminated on site because of the delicate multi-fiber structure and narrow tolerances involved. MPO/MTP connectors are therefore sold already terminated together with trunk cables. With this arrangement, customers have to plan line lengths precisely but are also assured top quality and short installation times. To achieve lower tolerances and better attenuation values, the American connectivity specialist US Conec developed the MTP connector. It has better optical and mechanical quality than the MPO. An MTP connector consists of a housing and a separate MT ferrule. The MT ferrule is a multi-fiber ferrule in which the fiber alignment depends on the eccentricity and positioning of the fibers and the holes drilled in the centering pins. The centering pins help control fiber alignment during insertion. Since the housing is detachable, the ferrules can undergo interferometric measurements and subsequent processing during the manufacturing process.

Conclusion

MPO/MTP connectors and fiber cables as the important part of the multi-fiber connection system, are designed for the reliable and quick operations in data centers. Fiberstore manufactures and distributes a wide range of MTP/MPO cable assemblies including trunk cables, harness cables and cassettes (or patch panels). And we also offer other kinds of transceiver and cable choices for your 40GbE applications, for example, HP JG709A 40GBASE-CSR4 QSFP+ transceiver, and Juniper QFX-QSFP-DAC-3M QSFP+ to QSFP+ passive copper cable, etc. Futhermore, customized service such as optional fiber counts, cable types and lengths are available.

Transceiver Solutions for Migrating to 40G Network

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 40 Gigabit 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: 40G LR4 QSFP+ transceiver, 40G SR4 QSFP+ transceiver and 40G QSFP+ BiDi transceiver. This article will give a comprehensive comparison on them.

40G 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.

Finisar FTL4C1QE1C Compatible 40GBASE-LR4 QSFP+ Transceiver

40G 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 40 Gigabit 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.

The Basics of 40GBASE-LR4 QSFP+ Transceiver

40GBASE QSFP+ (quad small form factor pluggable) portfolio offers 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, etc. And each kind of 40GBASE QSFP+ transceiver has its special applications. 40GBASE-LR4 QSFP+ transceiver is a common 40 Gigabit Ethernet connectivity option. Here is some basic information about 40GBASE-LR4 QSFP+ transceiver.

Introduction

40GBASE-LR4 QSFP+ module supports link lengths of up to 10 kilometers over a standard pair of G.652 single-mode fiber with duplex LC connectors. The 40 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed within the device. The letter “L” stands for long, the “R” denotes the type of interface with 64B/66B encoding and the numeral 4 indicates numeral 4 indicates that the transmission is carried out over a ribbon fiber with four singlemode fibers in every direction. Each lane has a 10 Gbit/s data rate. 40GBASE-LR4 QSFP+ transceiver modules are compliant with the QSFP+ MSA and IEEE 802.3ba 40GBASE-LR4. The picture below shows a Mellanox MC2210511-LR4 compatible 40GBASE-LR4 QSFP+ transceiver.

Mellanox MC2210511-LR4 Compatible 40GBASE-LR4 QSFP+ Transceiver

Two Types of 40GBASE-LR4 QSFP+ Transceiver

There are mainly two of 40GBASE-LR4 QSFP+ transceivers, 40GBASE-LR4 CWDM (coarse wavelength division multiplexing) QSFP+ transceiver and 40GBASE-LR4 PSM (parallel single-mode fiber) QSFP+ transceiver. This part mainly talks about these two 40GBASE-LR4 QSFP+ transceiver types.

40GBASE-LR4 CWDM QSFP+ transceiver, such as QSFP-40GE-LR4, contains a duplex LC connector for the optical interface. It can support transmission distance of up to 10km. A 40GBASE-LR4 CWDM QSFP+ transceiver converts 4 inputs channels of 10G electrical data to 4 CWDM optical signals by a driven 4-wavelength distributed feedback (DFB) laser array, and multiplexes them into a single channel for 40G optical transmission. Then the receiver module accepts the 40G CWDM optical signals input, and demultiplexes it into 4 individual 10G channels with different wavelengths.

40GBASE-LR4 PSM QSFP+ transceiver is a parallel single-mode optical transceiver with an MTP/MPO fiber ribbon connector. It also offers 4 independent transmit and receive channels, each capable of 10G operation for an aggregate data rate of 40G. The transmitter module accepts electrical input signals compatible with common mode logic (CML) levels. All input data signals are differential and internally terminated. The receiver module converts parallel optical input signals via a photo detector array into parallel electrical output signals. The receiver module outputs electrical signals are also voltage compatible with CML levels.

Applications

QSFP-40GE-LR4 supports 40GBASE Ethernet rate only, whereas the QSFP-40G-LR4 supports OTU3 data rate in addition to 40GBASE Ethernet rate. 40GBASE-LR4 QSFP+ transceivers are most commonly deployed between data-center or IXP sites with single mode fiber.

Fiberstore offers customers a wide variety of 40GBASE-LR4 QSFP+ transceivers for your high-density and low-power 40 Gigabit Ethernet connectivity options, including 40GBASE-LR4 CWDM QSFP+ transceiver and 40GBASE-LR4 PSM QSFP+ transceiver, like Cisco QSFP-40GE-LR4 40GBASE-LR4 QSFP+ transceiver. Fiberstore also provides wide brand compatible 40G QSFP+ transceivers, such as Brocade QSFP+, Dell QSFP+, Juniper QSFP+, Mellanox QSFP+, and HP QSFP+. Each fiber optic transceiver provided by Fiberstore has been tested to ensure its compatibility and interoperability. Please rest assured to buy.

Are You Ready for 40G and 100G?

Data centers regularly undertake their own great migration, to ever higher speed networks. 10G, unimaginable a decade ago, is now common in larger enterprises. And now many enterprises have to adopt 40 Gigabit Ethernet or even 100G in the aggregation and core layers of data center networks in order to meet the overall bandwidth demands of top-of-rack servers. The need is clear: a 40/100G Ethernet migration plan is quickly becoming a matter of survival. Is your network cabling optimized for this inevitable growth? Are you ready for 40G and 100G?

Fiber Transmissions at Higher Speeds

When moving to 40/100GbE, the most important difference in backbone and horizontal multimode applications is the number of fiber strands. 40GBASE-SR4 uses 8 strands in total, 4 strands to transmit and 4 to receive. 100GBASE-SR10 uses 10 lanes to transmit and another 10 lanes to receive for a total of 20 strands. In data centers and backbones, it may be possible to have 8 or 20 individual strands of fiber. However, those strands may take disparate paths from one end to the other and this can cause delay skew (known as bit skew) resulting in bit errors. For this reason, the 40/100GbE standards are written around fiber optic trunk assemblies that utilize a MPO/MTP multi-fiber array connector. Data is transmitted and received simultaneously on MTP interfaces through 10G simplex transmission over each individual strand of the array cable. In these assemblies, all strands are the same length. Also referred to as “parallel optics”, this construction minimizes bit/delay skew, allowing the receive modules to receive each fibers information at virtually the same time.

Copper Transmissions at Higher Speeds

The first 10GbE capable copper interface was developed for the 10GBASE-CX4 application. The physical requirements for this shielded four-lane copper connector is standardized under SFF-8470. As a passive assembly, the SFF-8470/CX4 cables have a reach of 15m. This assembly supports 10GbE, InfiniBand, FibreChannel and FCoE. These assemblies use twinax cable, constructed of two inner conductors with an overall foil covered by a braid shield. Due to their low latency, these cables are popular in supercomputing clusters, High Performance Computing and storage. As part of the 802.3ba 40/100GbE standard, multi-lane 40GBASE-CR4 and 100GBASE-CR10 was defined. This standard specifies the use of 4 and 10-lane twinax assemblies to achieve 40 and 100GbE speeds for distances up to 7m.

40/100G MPO/MTP System

MPO/MTP is available in both 12 and 24 strand termination configurations used at the end of a trunk assembly. A modular laser optimized multimode MPO/MTP system that supports 40G and 100G fiber optic networks includes trunks, harnesses, array cords, modules, and adapter plates. For 40GbE, a 12-fiber cabling solution with each channel featuring four dedicated transmit fibers and four dedicated receiver fibers is used. In general, the middle four fiber remain unused. Parallel transmission is also used for 100GbE with a 24-fiber solution or two 12-fiber solution.

MPO MTP cables

At present, 40GbE is taking over from 10GbE as the new high-growth market segment. Meanwhile, the 40GbE optics are universal in data center and the market of 100GbE is accelerating. Being prepared for 40/100G is essential: within a few short years higher-speed Ethernet will be common in data centers across all types of organizations. Fiberstore is ready. Fiberstore offers various optical communication products to meet diverse demands. For example, we provide 40GBASE-SR4 QSFP+ transceivers, like Finisar FTL410QE2C 40GBASE-SR4 QSFP+ transceiver and Mellanox MC2210411-SR4 40GBASE-SR4 QSFP+ transceiver, which are branded by famous companies and quality guaranteed.

Transceiver Choices for 40 Gigabit Ethernet

40GbE (Gigabit Ethernet) is Ethernet standard developed by the IEEE 802.3ba, enabling the transfer of Ethernet frames at speeds of up to 40 gigabits per second (Gbps). Now 40 Gigabit Ethernet is becoming more and more popular, suitable for high-speed, high-demand, and computing applications. For a 40GbE network, transceiver modules are one of the most basic components for transmission, used to plugged into either network servers or various of components such as interface cards and switches. 40GbE transceivers are being developed along several standard form factors. Some basic knowledge of 40GbE transceivers will be provided in the following text.

CFP Transceiver

The CFP (C form-factor pluggable) transceiver features twelve transmit and twelve receive 10Gbps lanes to support one 100GbE port, or up to three 40GbE ports. Its larger size is suitable for the needs of single-mode optics and can easily serve multimode optics or copper as well. The following picture shows a CFP transceiver. 40GBASE CFP transceiver modules are hot-swappable input/output devices that plug into a 40 Gigabit Ethernet CFP port of a switch or router. CFP modules offer customers versatile 40 Gigabit Ethernet connectivity options in core and distribution layers of data center, enterprise, and service provider networks. Main features of 40GBASE CFP modules include:

  • Support for 40GBASE Ethernet and OTU3 standards
  • Support for “pay-as-you-populate” model
  • Support for digital optical monitoring (DOM)
  • Variety of interface choices for 40 Gigabit Ethernet connectivity
  • Interoperability with respective industry IEEE- and/or OTU3-compliant interfaces
  • Support for the Cisco quality identification (ID) feature, which enables a Cisco switch or router to identify whether the module is certified and tested by Cisco
CFP 1310nm 10km Transceiver for SMF
CXP Transceiver

The CXP transceiver form factor also provides twelve lanes in each direction but is much smaller than the CFP and serves the needs of multimode optics and copper. The Roman number X means that each channel has a transmission rate of 10 Gbps. CXP is a kind of hot-pluggable transceiver with data rate up to 12×10 Gbps. It provides twelve 10 Gbit/s links suitable for single 100 Gigabit Ethernet, three 40 Gigabit Ethernet channels, or twelve 10 Gigabit Ethernet channels or a single Infiniband 12× QDR link. The C is the Roman numeral for 100 as a memory aid.

QSFP/QSFP+ Transceiver

The QSFP/QSFP+ (quad small-form-factor pluggable) is similar in size to the CXP and provides four transmit and four receive lanes to support 40GbE applications for multimode and single-mode fiber and copper today. It is the most popular interface of 40G transceivers now. Two main types of QSFP+ transceivers used in the data center are QSFP-40G-SR4 and QSFP-40GE-LR4. The following picture shows an Arista QSFP-40G-SR4 QSFP+ transceiver and a Cisco QSFP-40GE-LR4 QSFP+ transceiver. QSFP-40G-SR4 is used in 4x10G mode along with ribbon to duplex fiber breakout cables for connectivity to four 10GBASE-SR optical interfaces. 40GBASE-LR4 QSFP+ module supports link lengths of up to 10km over a standard pair of G.652 single-mode fibres with duplex LC connectors. In addition, there are other types of QSFP+ modules, such as QSFP-40G-ER4, 40GBASE-PLRL4, etc. Main features of 40GBase QSFP+ modules include:

  • Support for 40GBASE Ethernet
  • Flexibility of interface choice
  • Hot-swappable input/output device that plugs into a 40-Gigabit Ethernet QSFP+ switch port
  • Interoperable with other IEEE-compliant 40GBASE interfaces available in various form factors
  • Support for “pay-as-you-populate” model
QSFP-40G-SR4 and QSFP-40GE-LR4 QSFP+
Conclusion

Fiberstore offers 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. If you have any demand for the 40GbE components or product solutions, please contact Fiberstore team over sales@fs.com or have a livechat on www.fs.com.

The Basics of Dirrect Attach Cables

Dirrect attach cable (DAC), is a cost effective and proven solution for interconnecting networking applications. It can provide inexpensive and reliable connections using either copper cables or fiber cables. What is DAC? How copper DAC and fiber DAC differ from each other? Here is what you need to know about DACs.

DAC Definition

A direct attach cable is a fixed assembly that is purchased at a given length, with the connector modules permanently terminated to each end of the cable to connect switches to routers or servers. DACs are much cheaper than the regular optics, since the “transceivers” on both ends of DACs are not real optics and their components are without optical lasers. They are preferable choice for their low cost, low power consumption and high performances. DAC are made of the two kinds of cable materials: copper and optical fiber. They are respectively called direct attach copper cable and active optical cable.

DAC Assemblies—Copper

Direct attach copper cable is interchangeable and hot swappable with fiber optic modules. It is designed in either active or passive versions. It supports such multiple protocols as Gigabit & 10G Ethernet, 8G FC, FCoE and InfiniBand. Direct attach copper cable is a cost effective solution over optical transceivers and and cables for short reach applications. It can support higher data rates than traditional copper interfaces—from 4Gbps to 10Gbps per channel. The defect of direct attach copper cable is that it is heavy and bulky, making it difficult to be managed. Furthermore, due to the nature of electrical signals, direct attach copper cable is vulnerable to the effects of electromagnetic interference (EMI), such as undesirable responses, degradation, or complete system failure. Fiberstore offers various QSFP+ direct attach copper cables with different lengths for your 40G applications. For example, lengths of Juniper EX-QSFP-40GE-DAC-50CM, QFX-QSFP-DAC-1M and QFX-QSFP-DAC-3M compatible QSFP+ to QSFP+ passive copper cables are respectively 0.5m, 1m, and 3m.

0.5m Juniper EX-QSFP-40GE-DAC-50CM Compatible QSFP+ to QSFP+ Passive Copper Cable

DAC Assemblies—Fiber

Active optical cable (AOC) is an alternative to optical transceivers, eliminating the separable interface between transceiver module and optical cable. It meets Small Form-factor (SFF) standards. Compaired to direct attach copper cable, AOC weighs less and can support longer transmission distance. It is immune to electromagnetic energy since the optical fiber is dielectric (not able to conduct electric current). What’s more, it is an alternative to optical transceivers and it can eliminate the separable interface between transceiver module and optical cable. AOC has no EMI. However, it costs more than copper cable.

Active_Optical_Cables

Applications of DAC

Direct attach cables are widely applied in storage area network, data center, and high-performance computing connectivity. They suppoet high speed I/O applications in storage, networking and telecom markets. And they can also be sused in witches, servers, routers, network interface cards (NICs), and Host Bus Adapters (HBAs). There are many different kinds of DACs, they all have their specific applicayions. For example, 40G AOC is commonly used for short-range multi-lane data communication and interconnect applications.

Conclusion

Fiberstore offers a variety of high speed interconnect DAC assemblies including 10G SFP+ cables, 40G QSFP+ cables, and 120G CXP cables to satisfy the demands from 10G to 100G interconnection. Direct attach cables provided by Fiberstore can be customized to meet different requirements. And we also offer all kinds of high quality QSFP+ modules branded by many famous companies, like Brocade QSFP+, Dell QSFP+, Juniper QSFP+, Finisar QSFP+, Intel QSFP+, etc. You can buy from us with confidence.

Cisco 40GBASE QSFP+ Modules

Cisco 40GBASE 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 conectivity options provided by Cisco will be introduced.

Features and Benefits of Cisco 40GBASE QSFP+ Module

Main features of Cisco 40GBASE 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.

QSFP-40G-SR4-S QSFP+ and QSFP-40G-CSR4 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+ copper DACs include QSFP+ to QSFP+ copper DACs and QSFP+ to 4SFP+ copper DACs. Cisco QSFP+ copper DACs 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 QSFP+ 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 QSFP+ 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.

What Makes 40G Active Optical Cable So Popular?

40G active optical cable (AOC) is a high performance, low power consumption, long reach interconnect solution supporting 40G Ethernet, fiber channel and PCIE. It is widely used in many fields as well as promoting the traditional data center to step into optical interconnection. Compared to 40G copper direct attach cables and 40GBASE QSFP+ optics, what makes 40G AOC so popular?

What Is 40G AOC?

40G AOC, is a type of active optical cable for 40GbE applications that is terminated with 40GBASE QSFP+ transceiver on one end while on the other end, it can be terminated with QSFP+ connector, SFP+ connector, or LC/SC/FC/ST connector. Active optical cable uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable without sacrificing compatibility with standard electrical interfaces. QSFP+ AOC integrates four data lanes in each direction with 40Gbps aggregate bandwidth. Each lane can operate at 10Gbps with lengths ranging from one to 100m. It is compliant with the QSFP MSA and IEEE P802.3ba. The following picture shows the structure of an active optical cable and three different kinds of QSFP+ AOC.

Active_Optical_Cables

Advantages of 40G AOC

40G AOCs have great advantages over 40G copper DACs and 40GBASE QSFP+ optics. 40G AOCs cost lower than SR4 modules and do not need to use with extra fiber patch cables. In particular, 40G breakout AOCs, such as 40GBASE QSFP+ to 4xSFP+ or 40GBASE QSFP+ to 8xLC AOCs are cost-effective solutions to achieve 40G migration. Additionally, using AOCs, there are no cleanliness issues in optical connector and there is no need to do termination plug and test when troubleshooting, which can help user save more time and money. 40G AOCs achieve longer reach, have lower weight and tighter bend radius, which enables simpler cable management and the thinner cables allows better airflow for cooling. Besides, AOCs have better consistency and repeatability cabling performance. With the integration and sealed design, AOCs can avoid the influence of environment and vibration. Additionally, for troubleshooting, AOCs are more easier to manage. Because users do not need to do a seires of termination plug and test on-site as they do when using SR4 modules and patch cables.

Applications of 40G AOC

40G AOC is commonly used for short-range multi-lane data communication and interconnect applications, for it provides light weight, high performance, low power consumption, low interconnection loss, EMI immunity and flexibility. QSFP AOC supports InfiniBand QDR/DDR/SDR, Ethernet (10 and 40Gbps), Fibre Channel (8 and 10 Gbps), SAS and other protocol applications. AOCs are highly recommended to use in data center interconnection.

The market of active optical cables keeps growing and has a broad prospect. Fiberstore AOCs achieve high data rates over long reaches which provide solutions for high-performance computing and storage applications. We offer all kinds of QSFP+ cable and 40G QSFP products with high performance and quality guaranteed.

Cabling Connectivity Options for 40Gbps Infrastructure

Driven by growing bandwidth and network performance demand, data center network infrastructure is witnessing a transformation. The speed of data center now is increasing to 40 Gbps. Thus, new cabling infrastructure and cabling connectivity options are required. Here some commonly used cabling connectivity options for 40Gbps infrastructure will be introduced in this post.

Pluggable Modules: 40G QSFP+ Transceivers

Fiber optic transceiver is an electronic device that receives an electrical signal, converts it into a light signal, and launches the signal into a fiber. It also receives the light signal, from another transceiver, and converts it into an electrical signal. It is the key component in fiber optic transmission. The basic interface of 40G pluggable optical modules are 40GBASE-LR4 and 40GBASE-SR4 QSFP+ form factor.

40GBASE-LR4 QSFP+: 40GBASE-LR4 transceiver support with a link length up to 10 km over 1310nm single-mode fiber. It is most commonly deployed between data centers or IXP sites. The image below shows a Cisco QSFP-40G-LR4 compatible 40GBASE-LR4 QSFP+ transceiver.

Cisco QSFP-40G-LR4 Compatible 40GBASE-LR4OTU3 QSFP+ Transceiver

40GBASE-SR4 QSFP+: 40GBASE-SR4 transceivers are used in data centers to interconnect two Ethernet switches with 8 fiber parallel multimode fiber OM3/OM4 cables. It can support transmission distance up to 100 m with OM3 fiber and 150 m with OM4 fiber. The optical interface of 40GBASE-SR4 QSFP+ is MPO/MTP. The image below shows a Cisco QSFP-40G-SR4 compatible 40GBASE-SR4 QSFP+ transceiver.

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

In addition, for single-mode fiber transmission, there are 40GBASE-LR4 Parallel Single Mode (PSM) transceivers which are used to provide support for up to four 10Gbps Ethernet connections on a QSFP+ port over single mode fiber at distances up to 10 km. For multimode fiber transmission, QSFP+ extended SR4 transceivers are developed which is designed with optimized VCSEL with better performance of RMS spectral width compared with QSFP+ SR4. QSFP+ extended SR4 transceivers can support transmission distance up to 300 m with OM3 fiber and 400 m with OM4.

Passive & Active Direct Attach Copper Cables

The QSFP+ passive or active direct attach copper cables are designed with twinax copper cable and terminated with QSFP+ connectors. The main difference between passive QSFP+ DAC and active QSFP+ DAC is that the passive one is without the active component. They provide short distance inexpensive connectivity at up to 40Gbps rates and operate 4 independent 10G channels using the QSFP connector footprint. Each of the four channels can operate at multi-rate speeds Gigabit to 10Gbps. The image below shows QSFP-4SFP10G-CU1M compatible QSFP+ to 4SFP+ passive breakout copper cable.

Cisco QSFP-4SFP10G-CU1M Compatible QSFP+ to 4SFP+ Passive Breakout Copper Cable

Active Optical Cable (AOC) Assemblies

Active optical cable uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable without sacrificing compatibility with standard electrical interfaces. QSFP+ AOC is a high performance integrated cable for short-range multi-lane data communication and interconnect applications, for it provides light weight, high performance, low power consumption, low interconnection loss, EMI immunity and flexibility. QSFP+ AOC supports InfiniBand QDR/DDR/SDR, Ethernet (10 and 40Gbps), Fibre Channel (8 and 10 Gbps), SAS and other protocol applications. And hot-pluggable transceiver allows insertion and removal of devices without powering down the system. The image below shows QSFP-4X10G-AOC10M compatible QSFP+ to 4SFP+ active optical breakout cable.

Cisco QSFP-4X10G-AOC10M Compatible QSFP+ to 4SFP+ Active Optical Breakout Cable

Fiberstore offers a comprehensive solution for 40G fiber optic cabling connectivity. We support a full range of both copper cables and optical transceivers for 40GbE, compliant to the IEEE standards. For copper both QSFP+ to QSFP+ (40G to 40G) and QSFP+ to SFP+ (40G to 4x10G) cables enable short reach options. For longer distances Fiberstore offers a wide range of optical transceivers for various fiber types and reach requirements.

Upgrading to 40/100 Gigabit Ethernet

To support the changing and fast-growing bandwidth demands of data centers (DCs), the IEEE ratified standards for supporting 40 Gigabit Ethernet (40GE) and 100 Gigabit Ethernet (100GE), known as IEEE 802.3ba. 40GE and 100 GE belong to a family of network technologies that primarily are used in local area networks. As they are becoming more and more popular, it is very necessary to know more about them. This post offers a quick-reference guide to increase your familiarity with issues in the migration to 40 and 100GE systems.

Cabling Systems

Both 40 and 100 Gigabit Ethernet can be deployed using the same cabling systems in use today. Multi-mode will employ parallel optics using MPO interconnects and require additional cable infrastructure depending on the system deployed while single mode fiber will employ serial transmission and use LC or SC connectors. The approach used for the higher speed data rates is based on advanced transceiver technologies engineered to take advantage of the full bandwidth of laser optimized fibers. Both single mode fiber (SMF) and multi-mode fiber (OM3, OM4) were approved in the standard.

Standards
  • 40GBase-SR4: multimode fiber with four fiber pairs (OM3/OM4)
  • 40GBase-LR4: single-mode fiber pairs with 4 wavelengths a 10Gbit/s at 10 km
  • 40GBase-KR4: short distances in the backplane (4 pairs of wires)
  • 40GBase-CR4: twinax cable with 4 pairs
  • 100GBase-CR10: twinax cable with 10 pairs
  • 100GBase-SR10: multimode fiber with 10 fiber pairs (OM3/OM4)
  • 100GBase-SR10: single-mode fiber pairs with 4 wavelengths a 25Gbit/s at 10 km
  • 100GBase-ER4: single-mode fiber pairs with 4 wavelengths a 25Gbit/s at 40 km
Module Types

QSFP: The QSFP (quad small-form-factor pluggable) is the primary way of delivering 40GE and are now appearing in 100GbE-capable form. These present either MPO connectors for multi-mode optics or LC connectors for single-mode optics. It is similar in size to the CXP and provides four transmit and four receive lanes to support 40GbE applications. QSFP+ (quad small form-factor pluggable plus), as the updated version of QSFP, is a new multi-source agreement (MSA) for high speed application. QSFP+ gradually replace QSFP and is widely used by people as it can provide higher bandwidth. The following picture shows an Avaya AA1404001-E6 compatible QSFP+ transceiver.

Avaya AA1404001-E6 Compatible 40GBASE-LR4 QSFP+ Transceiver

CFP: The CFP (C form-factor pluggable) transceiver features twelve transmit and twelve receive 10Gb/s lanes to support one 100GbE port, or up to three 40GbE ports. CFP form factor optics are available in 40GbE and 100GbE varieties. Its larger size is suitable for the needs of single-mode optics and can easily serve multi-mode optics or copper as well. These present MPO connectors for multi-mode optics or SC connectors for single-mode optics. CFP modules use the 10-lane CAUI-10 electrical interface.

CFP2: The CFP2 is an evolution of the existing CFP form factor, using manufacturing and optics advances to reduce the size of the module to approximately half that of the original CFP, allowing for higher interface density. CFP2 modules use the 10-lane CAUI-10 electrical interface or the 4-lane CAUI-4 electrical interface.

Requirements and Objectives

40GE and 100GE fulfill the following requirements and objectives:

  • Preserve existing 802.3 frame format, minimum size, and maximum size.
  • Support high-speed switching, routing, and application functions in data centers.
  • Exhibit a bit error rate (BER) of 10-12 or better.
  • Provide support for optical transport network (OTN).
  • Provide specifications for operation over single-mode optical fiber, laser optimized multimode optical fiber, copper cables, and backplanes.
  • Support high-bandwidth applications such as video on demand (VoD) and high-performance computing (HPC).

The throughput and reliability of a 40/100 Gigabit Ethernet installation is directly related to the cabling, the choice of connectivity, and proper installation. Fiberstore’s superior cable and connectivity designs provides you with superior levels of performance and operation. We offer all kinds of cables and transceiver modules for your applications, such as Dell Force10 GP-QSFP-40GE-1SR 40GBASE-SR4 QSFP+ transceiver, or Juniper QFX-QSFP-DAC-3M compatible QSFP+ to QSFP+ passive copper cable, and so on. You can buy from us with confidence.

Introduction to Mode Conditioning Patch Cable

Mode conditioning patch cord (MCP) was developed as a solution for network applications where Gigabit Ethernet hubs with laser based transmitters are deployed. It is a special fiber optic patch cord and allows customer upgrading their hardware technology without the cost of upgrading fiber plant. In addition, MCP significantly improves data signal quality while increasing the transmission distance. The text gives some detailed information about mode conditioning patch cable.

What Is Mode Conditioning Patch Cable?

A mode conditioning patch cord is a duplex multi-mode patch cord that has a small length of single mode fiber at the start of the transmission leg, and also a single mode to multi-mode offset fiber connection part in this leg. There are two multi-mode fibers on one end and one multi-mode and one single mode fiber on the other end. It is fully compliant with IEEE 802.3z application standards. Mode conditioning patch cord causes the single mode transceiver to create a launch similar to a typical multi-mode launch. It is designed for long wavelength Gigabit Ethernet applications. The following picture shows the construction of a mode conditioning patch cable.

mode-conditioning-patch-cord2

How Does Mode Conditioning Patch Cable Work?

The basic principle behind the cord is that you launch your laser into the small section of single mode fiber. The launch of the light coming out of the equipment begins on a single mode fiber. The other end of the single mode fiber is coupled to multi-mode section of the cable with the core offset from the center of the multi-mode fiber. The light is launched on to the multi-mode fiber at a precise angle, giving the cable its mode conditioning properties. When we use such mode conditioning fiber optic patch cords, we need to connect the yellow leg which is the color of single mode to connect the transmit side of the equipment (single mode Gigabit transceiver) while we connect the orange leg which is the color of multi-mode to the receive side. The picture below shows how the single mode fiber is coupled to multi-mode section of the cable.

Mode-Conditioning-Fiber-Patch-Cable-1024x403

Why Do We Need Mode Conditioning Patch Cable?

Transceiver modules used in Gigabit Ethernet (1000 Base-LX) launch only single mode (1300nm) long wave signals, which poses a problem if an existing fiber network utilizes multi-mode cable. When a single mode signal is launched into a multi-mode fiber a phenomenon known as differential mode delay (DMD) can create multiple signals within the multi-mode fiber. This effect can confuse the receiver and produce errors. By allowing the single mode laser launch to be offset away from the center of the multi-mode fiber, mode conditioning patch cord reduces the effect of such differential mode delay and provides a much higher operational bandwidth by precisely aligning a single mode termination at the laser transmitter. This is essential for networks using 62.5/125 and 50/125 multi-mode optical fiber and may be specified for current multi-mode networks depending upon the system requirements.

Mode conditioning patch cables are with various options, from all types of connectors to different jackets and different lengths. A variety of fiber optic connectors are available for your convenience, including: LC/UPC, SC/UPC, FC/UPC, ST/UPC, LC/APC, SC/APC, FC/APC, and MTRJ. Fiberstore is a professional manufacturer and supplier, offering all kinds of fiber optic cables, including LC to LC fiber cable, SC fiber patch cable, MPO fiber cable, PM fiber patch cords, etc. You can get what you need from us.

Google Fiber Adds Chicago, Los Angeles to ‘maybe’ List

December 10, 2015
Lightwave Staff

1449778017103

Google Fiber says it has “invited” Chicago and Los Angeles to discuss bringing the company’s gigabit broadband services to their cities. Adding the two cities a€“ the largest with which Google Fiber has engaged so far a€“ brings to 18 the number of markets Google Fiber is active at some level. However, it is actually supplying services in parts of three of them a€“ Kansas City (Missouri and Kansas), Austin, TX, and Provo, UT.

Los Angeles and Chicago join Irvine, San Diego, and San Jose, CA; Portland, OR; Phoenix, AZ; Oklahoma City, OK; Louisville, KY; and Jackson and Tampa, FL, on Google Fiber’s list of “potential” markets (see map above). As with these other cities, Google Fiber has a checklist of information it needs and tasks it would like city leadership to perform to help the company determine whether it will move forward with fiber to the home (FTTH) deployments.

The company did not provide status information on these potential markets, or updates on roll out dates for the markets in the “upcoming” list a€“ Atlanta, GA; Charlotte and Raleigh-Durham, NC; Nashville, TN; San Antonio, TX; and Salt Lake City, UT.

The announcement came shortly after rival AT&T announced that it will roll out its gigabit FTTH service in an additional 38 markets (see “AT&T announces gigabit broadband expansion to 38 markets”). While Google Fiber captured significant early mindshare with its gigabit initiative, it has subsequently been surpassed in terms of actual deployments by such major service providers as AT&T and Comcast (see “Comcast markets 2-Gbps Gigabit Pro in seven states”). These providers, of course, often have the advantage of existing conduit and in-place pole attachment agreements that they can leverage to streamline deployments.

1000BASE-T Gigabit Ethernet over Category 5 Cable

Various copper and fiber choices are available on the market today. When deciding a cabling system, network managers should know how to choose the most appropriate cabling system for their network infrastructure in the long run. Many of the cabling installed today inside buildings is Category 5. Many factors, like punch down blocks, and patch panel connections, affect the performance of 1000BASE-T technology if not correctly implemented. This article gives an introduction to 1000BASE-T Gigabit Ethernet operation over the installed base of Category 5 cabling.

1000BASE-T and Category 5 Cabling

1000BASE-T is a type of gigabit Ethernet networking technology that uses copper cables as a medium. 1000BASE-T uses four pairs of Category 5 unshielded twisted pair cables to achieve gigabit data rates. There should be no need to replace existing Category 5 cabling to use 1000BASE-T. The standard is designated as IEEE 802.3ab and allows 1Gbps data transfers for distances of up to 330 feet. 1000Base-T came into wide use in 1999, gradually replacing fast Ethernet for wired local networks simply because it was 10 times as fast. Equipment and cables are very similar to previous Ethernet standards and by 2011 were very common and economical. These were the biggest factors that ensured this standard’s wide acceptance. The 1000BASE-T product is designed to operate over Category 5 cabling. The image below shows how 1000BASE-T works.

1000BASE-T

Gigabit Bandwidth over Category 5 Cabling

1000BASE-T uses a symbol rate of 125 Mbaud (A 125 Mbaud symbol rate is required because 100BASE-TX uses 4B/5B coding), but it uses all four pairs for the link and a more sophisticated five-level coding scheme. In addition, 1000BASE-T sends and receives simultaneously on each pair. Combining 5-level coding and 4 pairs allows 1000BASE-T to send one byte in parallel at each signal pulse. 4 pairs 125 Msymbols/second X 2 bits/symbol = 1Gbps.

Problems During Cable Installation

Of course, it isn’t quite this simple. In addition to moving the symbols across the link, 1000BASE-T must also deal with the effects of return loss and crosstalk, and other factors.

Return loss measures the amount of reflected signal energy resulting from impedance changes in the cabling link. If too much energy is reflected back onto the receiver, the device does not perform optimally. Factors that affect the return loss are:

  • The number of transition points, as there is a connection through an RJ-45 to another connector, a patch panel, or device at each transition point.
  • Removing the jacket that surrounds the four pairs of twisted cable. When RJ-45 connections are made, this is minimized to 1 1/4 inch (32 mm).
  • Untwisting any pair of the twisted-pair cabling. It is important that any untwisting be minimized to 3/8 inch (10 mm) for RJ-45 connections.
  • Cabling or bundling of multiple Category 5 cables. If not correctly implemented, this can adversely affect all cabling settings.

Crosstalk is unwanted signals coupled between adjacent wire pairs. Since 1000BASE-T uses all four wire pairs, each pair is affected by crosstalk from the adjacent three pairs. Near-end crosstalk (NEXT) is crosstalk that appears at the output of a wire pair at the transmitter (near) end of the cable. Far-end crosstalk (FEXT) is a measure of the unwanted signal coupling from a transmitter at the near-end into a neighboring pair measured at the far-end. Crosstalk is characterized in reference to the transmitter.

Conclusion

For optimum performance of your 1000BASE-T product, it is important to fully qualify your cable installation and ensure that it meets or exceeds Category 5 specifications. Fiberstore provides various Category 5 cables and 1000BASE-T optical transceivers for your applications. For example, Finisar FCLF-8520-3 1000BASE-T copper SFP RJ-45 transceiver, and Cisco GLC-T 1000BASE-T SFP copper RJ-45 transceiver, are compliant with the Gigabit Ethernet and 1000BASE-T standards as specified in IEEE 802.3 and 802.3ab. These SFP transceivers link your switches and routers to the network. They are 100% functionally tested, and compatibility is guaranteed.

10GBASE SFP+ Modules Overview

10GBASE SFP+ module, a 10GbE optics using the same physical form factor as a gigabit SFP, is a new protocol that will support the link lengths of a standard Fiber Distributed Data Interface (FDDI)-grade multi-mode fiber (MMF). When using this type of technology with 2000 MHz km MMF (OM3), designers can achieve longer link lengths and transmit signals for much longer distances without interference or noise interrupting the signal. 10GBASE SFP+ modules are commonly used transceivers in the market. Before investing in 10GBASE SFP+ modules, there are some things you need to know.

Benefits and Features of 10GBASE SFP+ Modules

The benefits and features of the 10GBASE SFP+ modules are numerous.

  • 10GBASE SFP+ module is one of the best in the industry. It provides the functionality that is needed to help transmit signals fast without any noise. Some of these devices have extended operating temperature range in addition to supporting a wide range of link lengths. The most common length lengths are 220m, 300m, and 400m.
  • 10GBASE SFP+ module features a small footprint, which is a premium in designs where it’s important to keep the overall design compact.
  • 10GBASE SFP+ module also supports the 10GBASE Ethernet and OTU2/OTU2e.
  • 10GBASE SFP+ modules are hot-swappable, which means that they have the ability to switch in and out of the device without powering it down. This is an incredible convenience. As long as the devices are compatible, the replacement or repair process is easy. This feature also provides flexibility of integrate the devices in the interface of choice.
  • 10GBASE SFP+ module supports the digital optical monitoring capability, making monitoring and diagnostics much easier. When managers need to make decisions in real time, they can make them without significant effort because of the digital monitoring capability.
10 Gigabit Ethernet SFP+ Options

10GBASE SFP+ transceivers are multi-purpose optical modules for 10Gbit/s data transmission applications at 850nm, 1310nm and 1550nm. There are several kinds of SFP+ transceivers for 10 Gigabit Ethernet, 10GBASE-SR SFP+, 10GBASE-LR SFP+, 10GBASE-LRM SFP+, 10GBASE-ER SFP+, and 10GBASE-ZR SFP+. 10GBASE-SR SFP+ supports up to 300m link length with 2000 MHz/km MMF (OM3). 10GBASE-LR SFP+ supports up to 10km link length on standard single-mode fiber (SMF). 10GBASE-LRM SFP+ supports up to 220m link length with 50um or 62.5um multi-mode fiber links. 10GBASE-ER SFP+ has a standard reach of 30 km over single-mode fiber. And 10GBASE-ZR SFP+ are designed for 80km distances. There are various 10GBASE SFP+ transceivers branded by famous brands, like Cisco, HP, Juniper, Brocade, etc. For example, Cisco SFP-10G-SR-X 10GBASE-SR/SW SFP+ transceiver, and Finisar FTLX1471D3BTL 10GBASE-LR SFP+ transceiver, they are both with high quality. The following picture shows a Fortinet FG-TRAN-SFP+LR 10GBASE-LR SFP+ transceiver.

Fortinet FG-TRAN-SFP+LR Compatible 10GBASE-LR SFP+ Transceiver

Applications of 10GBASE SFP+ Modules

10GBASE SFP+ modules offer customers a wide variety of high-density and low-power 10 Gigabit Ethernet connectivity options for data center, enterprise wiring closet, and service provider transport applications. These devices are flexible and have a wide variety of options for the data centers, enterprise wiring closets, and service provider transport applications. Because they are so flexible, they are often used in the industry. The transceivers are ideally suited for datacom and storage area network (SAN/NAS) applications based on the IEEE 802.3ae and Fibre Channel standards.

To accommodate an ever increasing spectrum of 10 Gigabit Ethernet applications, Fiberstore offers various 10GBASE SFP+ transceiver types, suitable for different media and distance reaches. All of our SFP+ 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.

Introduction to QSFP+ Active Optical Cable

QSFP active optical cable (AOC) is a high performance, low power consumption, long reach interconnect solution supporting 40G Ethernet, fiber channel and PCIE. It is widely used in many fields as well as promoting the traditional data center to step into optical interconnection. A brief introduction to QSFP+ active optical cable is given in this post.

What Is QSFP+ Active Optical Cable?

Active optical cable uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable without sacrificing compatibility with standard electrical interfaces. It is commonly used for short-range multi-lane data communication and interconnect applications, for it provides light weight, high performance, low power consumption, low interconnection loss, EMI immunity and flexibility. Active optical cable provides optimum link performance, high reliability, inter-operability and ease of installation. QSFP+ AOC is a high performance integrated cable for short-range multi-lane data communication and interconnect applications. It integrates four data lanes in each direction with 40Gbps aggregate bandwidth. Each lane can operate at 10Gbps with lengths ranging from one to 100m. QSFP AOC supports InfiniBand QDR/DDR/SDR, Ethernet (10 and 40Gbps), Fibre Channel (8 and 10 Gbps), SAS and other protocol applications. It is compliant with the QSFP MSA and IEEE P802.3ba. High-density QSFP interface provides a compliant connection meeting QSFP+ Multi-Source Agreement (MSA) requirements. And hot-pluggable transceiver allows insertion and removal of devices without powering down the system.

QSFP+ to QSFP+ Active Optical Cable

QSFP+ to QSFP+ active optical cable is a 40Gb/s parallel active optical cable which transmits error-free parallel 4×10Gb/s data over multi-mode fiber (MMF) ribbon cables. QSFP+ to QSFP+ AOC assemblies provide 4 fully duplex channels per cable supporting signal transmission rates up to 10Gb/s & 14Gb/s per channel. QSFP+ to QSFP+ active optical cables are permanently attached to the fiber, with no air gaps, providing protection from environmental contaminants and other user disturbances during installation. The QSFP+ to QSFP+ active optical cable interface is based on the SFF-8436 industry standard, while also meeting the requirements of the 40GBASE-SR4 Ethernet and Infiniband SDR, DDR, QDR & FDR standards. The following image shows an Extreme Networks 10315 QSFP+ to QSFP+ active optical cable.

Extreme 10315 QSFP+ to QSFP+ Active Optical Cable

QSFP+ to 4SFP+ Active Optical Cable

QSFP to 4 SFP+ active optical (breakout) cable is a 4×10Gb/s parallel active optical cable which transmits four separate streams of 10Gb/s data over ribbon cables in a point-to-multipoint configuration. The cable contains a QSFP+ module on one end and four separate SFP+ modules at the other ends. Based on proven VCSEL array technology and designed with MSA-compliant QSFP+ and SFP+ high-density connectors, these cables are compact, lightweight, and low power. QSFP+ to 4SFP+ active optical cable is ideally suited for high-density 10G Ethernet, InfiniBand QDR, and other datacom and high-performance computing applications. The following image shows a Cisco QSFP-4X10G-AOC7M QSFP+ to 4SFP+ active optical breakout cable.

Cisco QSFP-4X10G-AOC7M QSFP+ to 4SFP+ active optical breakout cable

The market of active optical cables keeps growing and has a broad prospect. Fiberstore AOCs achieve high data rates over long reaches which provide solutions for high-performance computing and storage applications. AOC products such as 10G SFP+ AOCs, 40G QSFP+ AOCs, QSFP+ to 4SFP+ AOCs offered by Fiberstore are with high performance and quality guaranteed. You can find what you need from us.

Active Optical Cable for High-speed Transmission

There is no question that we live in a high-speed world. Active optical cable (AOC), especially parallel multi-lane cables using QSFP+ modules, is one of the most important devices used by high-speed interconnects, such as InfiniBand, and accurate cable testing is necessary to ensure reliable data transmissions and interoperability. What do active optical cables specifically bring to the table and why are they the way to go? Here is some detailed information about active optical cables.

What Is Active Optical Cable?

What is active optical cable? Let’s start with the basic definition that you would stumble upon if you happen to plug the term into a search engine: A specialized optical cable that uses electrical-to-optical conversion on the cable ends to improve speed and distance performance of the cable without sacrificing compatibility with standard electrical interfaces. A picture of Cisco QSFP-4X10G-AOC1M QSFP+ to 4SFP+ AOC is shown below.

Cisco QSFP-4X10G-AOC1M QSFP+ to 4SFP+ AOC

Advantages of Active Optical Cables

There are a number of reasons users are jumping to active optical cables. Primarily, these cables offer both higher bandwidth and a longer reach with a better footprint than current copper cables. Active optical cables provide lighter weight, smaller size, EMI immunity, lower interconnection loss, and reduced power requirements. Five meters of copper cabling weighs in at roughly a kilo. Ten meters of AOC weighs less than 150g. That weight difference means significantly less chance of damage to switch ports, less maintenance and better server utilization. Lighter and thinner cables are also easier to manage, require less space, and are easier to maintain.

Secondly, a key difference between copper, whether passive or active, and active optical is in bit error rates over distance. Beyond five meters, passive copper begins to suffer excessive bit error rates. Active copper improves range to around 15 meters, for roughly the same cost as active optical cable. Active optical cable for its part can operate reliably up to 100 meters, while the latest AOC products are extending their reach to 1km.

Thirdly, in comparison with transceiver products, active optical cables have the advantage of much greater simplicity, and potentially of reliability, as they are factory terminated, and there is no risk of mis-matching polarities, dirt entering the assemblies, or different manufacturers’ tolerance mismatching.

Applications of Active Optical Cables

Industry-leading active optical cables can achieve 40Gbps data rates over long reaches up to 10km, using a fraction of the power while providing streamlined installation. Low-power AOC integrated cable solutions provide less expensive, reliable transport for aggregated data rates up to 40Gbps. The active optical cables offer customers the flexibility of traditional optical modules by interfacing to systems via a standard QSFP MSA connector. QSFP+ to MPO optical cables allow an easy connection to separately installed single-mode fiber through the attached MPO connectors. Both product versions are electrically compliant with the QSFP+ interface InfiniBand, SDR (single data rate), DDR (double data rate), QDR (quad data rate), Ethernet (10 and 40Gbps), Fibre Channel (8 and 10Gbps), SAS (6Gbps) and other protocol applications. QSFP+ AOC can be used as a direct replacement for traditional copper cables with the added benefits of a lighter weight and smaller diameter solution for cable lengths from 1m to 100m. It can also be used to replace a pair of transceivers proving equivalent performance at a lower price.

Fiberstore is a professional manufacturer and supplier, which offers a large amount of cables and transceivers for your 40GbE applications. Fiberstore provides a large variety of active optical cables branded by major brands, like Cisco, HP, Juniper, Brocade and Finisar. For example, Juniper JNP-QSFP-DAC-10MA QSFP+ to QSFP+ AOC, and Finisar FCBG110SD1C03 SFP+ to SFP+ AOC, they both are suitable for very short distances and guaranteed with a limited lifetime warranty.