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.

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.

A Guide to 40 Gigabit Ethernet

The 802.3ba Ethernet standard introduced by the IEEE in June 2010 was in response to the increasing bandwidth demands facing data centers, paving the way for the introduction of 40Gb/s and 100Gb/s Ethernet operations. As you begin to think about the future of your network, understanding all the 40 Gigabit Ethernet (40GbE) and 100 Gigabit Ethernet (100GbE) optical components can be confusing. In this post, a brief overview of the current 40 Gigabit Ethernet to aid in planning for future high-performance Ethernet needs will be given.

What Is 40 Gigabit Ethernet?

40GbE is a standard that enables the transfer of Ethernet frames at speeds of up to 40 gigabits per second (Gbit/s). The 40GbE standard is intended for local server connectivity. One of the most attractive characteristics of 40 Gigabit Ethernet is broad applications and design flexibility. 40 Gigabit Ethernet runs on quad small form factor pluggable (QSFFP) cabling, a high-density fiber connector with 12 strands of fiber. According to the task force, 40GbE fulfills the following requirements and objectives:

• Preserve existing 802.3 frame format, minimum size, and maximum size.
• Support high-bandwidth applications such as video on demand (VoD) and high-performance computing (HPC).
• 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 multi-mode optical fiber, copper cables, and backplanes.

How Does 40 Gigabit Ethernet Work?

40 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. The 40 Gigabit Ethernet specification calls for a 12-fiber cabling solution, implemented using eight of the twelve fibers in an MPO connector, with each channel featuring four dedicated transmit fibers and four dedicated receive fibers. The middle four fibers remain unused, or dark. Each Tx/Rx pair is operating at 10G.

40 Gigabit Ethernet Cables

Cabling for 40 Gigabit Ethernet can be optical fiber or copper. The supportable channel length depends on the cable and the transceiver type. With regard to connectors, the only significant change outlined in the 802.3ba standard is the use of MPO (Multi-Fiber Push On) type connectors at the multi-mode transceivers to support the multi-fiber parallel optics channels. For data center environments operating at 40Gbps, OM3 and OM4 multi-mode cabling is generally recommended because its reach supports a wider range of deployment configurations compared to copper solutions, and the cost is lower compared to single-mode solutions.

40 Gigabit Ethernet Transceivers

40 Gigabit Ethernet transceivers are being developed along several standard form factors. The C form-factor pluggable (CFP) transceiver features 12 transmit and 12 receive 10Gbps lanes to support up to three 40 Gigabit Ethernet ports. Its larger size is suitable for the needs of single-mode optics and can easily serve multi-mode optics or copper as well. The CXP transceiver form factor also provides 12 lanes in each direction, but is much smaller than the CFP and serves the needs of multi-mode optics and copper. The quad small form-factor pluggable (QSFP) is similar in size to the CXP and provides four transmit and four receive lanes to support 40 Gigabit Ethernet applications for multi-mode fiber and copper. And quad small form-factor pluggable plus (QSFP+) gradually replaces QSFP and is widely used by people as it can provide higher bandwidth. The picture below shows a Cisco WSP-Q40GLR4L compatible QSFP+ transceiver.

Migrating to 40 Gigabit Ethernet will prove very cost-effective for those who do it right. One critical step is to choose appropriate cables and transceivers. Fiberstore is a professional manufacturer and supplier, which offers a large amount of cables and transceivers for your 40GbE applications. For example, HP 805755-B21 compatible QSFP+ transceiver, and Juniper JNP-QSFP-4X10GE-IR compatible QSFP+ transceiver offered by Fiberstore are cost-effective and high-performance transceiver modules fully compatible with major brands.

Introduction to QSFP+ Transceiver Module

Transmission speeds are continuing to rise as consumers demand ever higher performance from a variety of communications devices. If you are thinking about upgrading your server network connections, you may want to know about an emerging plug standard called QSFP+, which is now widely used by people as it can provide high bandwidth. Here is what you need to know about QSFP+ transceiver modules.

What Is QSFP+ Transceiver Module?

To know what a QSFP+ transceiver is, you need to understand QSFP transceiver first. QSFP (quad small form-factor pluggable) is a compact, hot-pluggable transceiver used for data communications applications. It interfaces networking hardware to a fiber optic cable or active or passive electrical copper connection. It is an industry format jointly developed and supported by many network component vendors, allowing data rates from 4x10 Gbit/s. The format specification is evolving to enable higher data rates. The QSFP specification accommodates Ethernet, Fibre Channel, InfiniBand and SONET/SDH standards with different data rate options. QSFP+ (quad small form-factor pluggable plus), as the updated version of QSFP, is a new multi-source agreement (MSA) for high speed application, such as 40G-BASE, which provide four channels of data in one pluggable interface. Each channel is capable of transferring data at 10Gbps and supports a total of 40Gbps. QSFP+ gradually replace QSFP and is widely used by people as it can provide higher bandwidth. QSFP modules increase the port-density by 3x-4x compared to SFP+ modules. The following picture shows a Juniper QSFPP-40GBASE-LR4 compatible 40GBASE-LR4 QSFP+ transceiver module.

Key Features of QSFP+ Transceiver

• 4 channels in one interface, providing 3 to 4x density of, SFP+ and XFP
• Meets QSFP+ requirements up to 10 Gbit/s per channel, total 40G interface
• Cages accommodate belly-to-belly mounting
• Heat sinks and lightpipes available
• Compliant with QSFP+ MSA and IEEE Standard 802.3ba
• Quick release latching system
• Low power dissipation

Installing a QSFP+ Transceiver

Perform the following procedure to install an QSFP+ transceiver:

• 1. Remove the module from its shipping container and store the packaging material in a safe location.
• 2. Remove the dust cover from the chassis QSFP+ slot.
• 3. If you are installing the transceiver in the top QSFP+ slot, position the transceiver with the handle facing up. If you are installing the transceiver in the bottom slot, position the transceiver with the handle facing down.
• 4. Slide the module into the slot until it clicks into place.
• 5. Repeat steps 1 to 4 if you have other QSFP+ transceivers to install.

If you are ready to attach the fiber optic cable to the transceiver, continue with removing the dust cover from the transceiver, and then inserting the fiber optic cable to the port on the transceiver, until it clicks in place. Otherwise, repeat steps 1 to 4 to install the remaining QSFP+ transceiver(s) in the line cards. Do not remove the dust cover from the installed QSFP+ transceiver until you are ready to install the fiber optic cable.

Applications of QSFP+ Transceiver

QSFP+ is the I/O cable form factor approved for use in data center applications including InfiniBand and 40G Ethernet. The 40Gbps QSFP+ transceiver is well suited for 40GBASE-SR4 and 40GBASE-LR4 applications. It combines the higher density attractions of parallel modules with some of the key advantages normally associated with SFP+ based modules. It is intended for use short reach applications in switches, routers and data center equipment where it provides higher density and lower cost when compared with standard SFP+ modules. And, QSFP+ transceivers are designed to carry Serial Attached SCSI, QDR (40G) and FDR (56G) Infiniband, and other communications standards. The QSFP+ transceiver is the dominant transceiver form factor used for 40 Gigabit Ethernet applications.

Fiberstore offers you a large number of QSFP+ transceiver modules branded by many famous companies, like Cisco, Juniper, HP, and Finisar. For example, Cisco QSFP-40G-SR4-S 40GBASE-SR4 QSFP+ transceiver, Finisar FTL410QD2C 40GBASE-SR4 QSFP+ Transceiver, and HP 805755-B21 40GBASE-SR4 QSFP+ transceiver, all those QSFP+ transceivers offered by Fiberstore are the most cost-effective standards-based transceiver modules and fully compatible with major brands and backed by a lifetime warranty.