Tag Archives: 40G QSFP+ AOCs

40G AOC Assemblies: Which One Is Perfect for You?

Direct attach copper cables (DACs) and active optical cables (AOCs) are widely used in data centers to support high transfer rates between switches, servers and storage devices. But compared with DAC, AOC cables have more advantages. And now 40 Gigabit Ethernet prevails in higher data transmission, which leads to the popularity of 40G AOCs such as 40G QSFP+ to 4xSFP+ AOC, 40G QSFP+ to 8xLC AOC, 40G QSFP+ to QSFP+ AOC, etc. However, another problem arises. Facing a large number of types of 40G AOC cables, do you know which one is perfect for your network? This post may help you solve this problem.

What Is 40G AOC?

As we all know, active optical cable (AOC cable) is a kind of 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, which is different from direct attach copper cables. And 40G AOC is a type of active optical cable that is terminated with 40GBASE QSFP+ connector on one end. And on the other end, it can be terminated with LC connectors, QSFP+ connectors or SFP+ connectors. The 40G AOC offers four independent data transmission channels and four data receiving channels via the multimode ribbon fibers, and each capable of 10Gb/s operation. With the advantages of high transmission rate, long transmission distance and low energy consumption, 40G AOC cable is ideal for data center and other applications.

40g aoc cable

Advantages of 40G AOCs

Compared with 40G DACs (direct attach cables), 40G AOCs have great benefits.

  • 40G AOCs have longer reach, lower weight and tighter bend radius, which allows for simpler cable management and better airflow for cooling.
  • 40G AOCs do not need to use extra fiber patch cables, which can save cost.
  • Deploying AOCs can simplify the troubleshooting process, for there are no cleanliness issues in optical connector and users do not need to do termination plug and test.
Different Types of 40G AOCs: Which One Is Perfect for You?

Since there is a limitation of copper cables, nowadays various types of 40G AOCs have been launched in the market. Here is a simple overview of 40G AOCs.


40G QSFP+ to QSFP+ active optic cables are a high performance, low power consumption, long reach interconnect solution supporting 40G Ethernet, Fibre Channel and PCIe. It is compliant with the QSFP MSA and IEEE P802.3ba 40GBASE-SR4. 40G AOC has four full duplex lanes, where each lane is capable of transmitting data at rates up to 10Gb/s, providing an aggregated rate of 40Gb/s.


40G QSFP+ to 4xSFP+ AOC

As its name shows, the 40G QSFP+ to 4xSFP+ AOC contains a 40G QSFP+ connector on one end and four separate 10G SFP+ connectors at the other ends. It is intended for 40G to 4×10G applications. This 40G to 10G AOC is a high performance cable for short-range multi-lane data communication and interconnect applications. For typical application, users can install this splitter active optical cable between an available QSFP+ port on their 40 Gbps rated switch and feed up to four upstream 10G SFP+ enabled switches. Each QSFP+ to SFP+ splitter AOC descriptions a single QSFP+ connector rated for 40Gbps on one end and four SFP+ connectors on the other, each rated for 10Gb/s. With this special features, 40G QSFP+ to 4xSFP+ AOC offers a cost-effective ways for IT professionals for merging 40G QSFP+ and 10G SFP+ enabled host adapters, switches and servers.


40G QSFP+ to 8xLC AOC

40G QSFP+ to 8xLC AOC also has four full duplex parallel channels. And transmission data rate of each channel is up to 10.3Gbit/s. It provides connectivity between devices using QSFP+ port on one end and 8xLC connectors on the other end. This AOC offers 40GbE systems the ability to connect 10G switches or adapter cards. And they are suitable for short distances and provide a highly cost-effective way to connect within racks and across adjacent racks.



As an alternative to copper links in high-performance computing and data center environments, active optical cables keep growing and have a great prospect. And 40G AOCs play an important role in many fields as well as enhancing the process of the traditional data center to step into optical interconnection. Choosing a right type of 40G AOCs also has profound significance. FS.COM supplies various kinds of 40G AOCs to meet your demands. Welcome to visit FS.COM for more detailed information.

Active Optical Cable (AOC Cable) Overview

In respond to the demand for a higher data bandwidth, active optical cable (AOC cable) has came into being to satisfy different cloud computing applications. Active optical cable is a term used to describe a cable that mates with standard electrical interfaces. The electrical-to-optical conversion on the cable ends is adopted to enhance the transmission speed and distance of the cable without sacrificing compatibility of standard electrical interfaces. This article will give a general introduction of active optical cable (AOC) and its most popular product in the current market.

Structure of Active Optical Cable (AOC)

AOC cable mainly consists of two parts- the fiber optic connector and fiber cable. The connection between fiber cable and connectors is not separable. If the connector or cable needs to be changed, they should be removed together. The electrical and optical signal conversion can be achieved right through each ends of optical fiber.

active optical cable (AOC cable)

Advantages of Active Optical Cable (AOC)

However, people may wonder the reasons why choosing active optical cable over direct attach copper cable. Here are some advantages of using active optical cable:

1) Although both cables are used for short range data communication, active optical cable is able to provide a longer reach than direct attach copper cable among devices.

2) Active optical cable has a higher bandwidth because its signal transmits through optical fiber as optical signal which transmits faster than electrical signal in copper cable. The maximum throughput of AOC cable is up to 40 Gbps with QSFP+.

3) The weight of active optical cable is lighter than copper cable due to the optical fiber material. It is possible for AOC cable to achieve a simpler cable management with a lower weight.

4) EMI (electromagnetic interference) immunity is another benefit of active optical fiber. EMI is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling or conduction. Since the optical fiber is a kind of dielectric which is unable to conduct electric current, active optical cable will not be affected by the electromagnetic energy.

Applications of Active Optical Cable (AOC)

Active optical cable has been applied to different fields. The followings are the most typical applications for AOC cable:

1) Infiniband QDR, DDR and SDR interconnects

2) Data aggregation, backplane and proprietary density applications

3) PCI-Express, SAS/SATA, Fiber Channel compatible interconnect

4) 40GBE and 10GBE interconnects

5) 10G, 40G telecom connections

6) Hubs, switches, routers, servers

7) Ethernet 10G, 40G

8) Data centers

9) High performance computing clusters

Popularity of 40G Active Optical Cable

Nowadays 40G QSFP+ active optical cable has become one of the most popular products in the market. It is an active optical cable used for 40 GbE terminated with 40GBASE QSFP+. Particularly, 40G breakout active optical cables, such as 40GBASE QSFP+ to 4xSFP+ AOC or 40GBASE QSFP+ to 8xLC AOC, are cost-effective solutions for 40G to 10G migration.


Active optical cable market accounts for a great share and is still booming for further development. The interconnection in short range and high speed between devices makes active optical cables practical in data center. As the technology matures, the application of active optical cable will be migrated to higher speed transmission in the future.