All You Need to Know about 56G QSFP+ to QSFP+ DAC Twinax Cable

DAC is the short name for direct attach cable. Currently, there are many different types of DAC twinax cables on the market such as SFP+ DAC Cable and QSFP DAC Cable. Terminated with transceiver-style connectors, they are designed to be used in the same ports as a typical SFP+ or QSFP transceiver, with no need for adaptors or converters, replacing two optical modules and a connectorized optical fiber with a twinax copper cable assembly. Here in this post, we will mainly focus on 56G QSFP+ to QSFP+ DAC Twinax Cable.

Basics on 56G QSFP+ to QSFP+ DAC Twinax Cable

The 56G QSFP+ to QSFP+ DAC twinax cable, as implied in the name, uses QSFP+ MSA and by using the inexpensive copper twinax cable with QSFP+ connectors on both sides, and provides 56 Gigabit Ethernet connectivity between devices with QSFP+ interfaces,which is suitable for very short distances and offers a highly cost-effective way to establish a 56 Gigabit link connectivity. Unlike 40G (10Gx4) QSFP+ DAC twinax cable, a kind of 40gb ethernet cable, the 56G QSFP+ DAC twinax cable is designed for 56G (14Gx4) InfiniBand FDR interconnecting networking applications such as high-performance computing (HPC), enterprise networking including top-of-rack switching and network storage markets.


The 56G QSFP+ DAC twinax cable is fully comply with QSFP+ Multi-Source Agreement (MSA) standards SFF-8436 and InfiniBand FDR specifications. And it is developed specifically as a cost-effective and lower-power alternative to 56G QSFP+ optics and 56G QSFP+ active optical fiber cable (QSFP+ AOC).

Specification and Features of 56G QSFP+ to QSFP+ DAC Twinax Cable

Now, many suppliers can provide 56G QSFP+ DAC twinax cable for customers. The key features and specification for these products are more ore less the same. Here, we take the generic compatible 56G QSFP+ cable DAC from FS for example.


specification for 56g dac

Key Features

  • Lower cost than 56G QSFP+ optics and active optical cable (AOC)
  • Maximum aggregate data rate: 56 Gb/s (4 x 14Gb/s)
  • Compliant with Infiniband QDR/DDR/FDR data rates
  • Hot-pluggable QSFP+ 38-PIN footprint
  • Low Insertion Loss and power consumption
  • Operating temperature range: 0 to 70°C


56G QSFP+ to QSFP+ DAC twinax cables are passive optic cables designed with high performance, low power consumption, long reach interconnect solution supporting 56G Ethernet. For suppliers like FS, their 56G QSFP+ to QSFP+ DAC and other twinax cable offer compatibility with a huge range of vendors, enabling the connectivity customers need within the Top of Rack and End of Row environments.

Do You Really Need a White Box Switch?

Although white box switches have been emerged for years, many people still tend to consider switches first from branded companies first when buying a fiber optic switch. The adoption of white box switch has been limited to niche companies that have large engineering departments. Over the years, the market of fiber optic market has been dominated by select vendors like Cisco, HP, Arista and Juniper. However, white box switch is coming to break the ice.

White Box Switch: What’s It?

The phrase “white box” has long been used to apply to no-name computers. The same ODMs (original design manufacturers) that produced them are getting into the game of manufacturing white-box switches. White-box switches look just like any other switch, but they are not installed with operating systems (OS). Since every switch needs an operating system, white box switches are useless without software. The OS can be chosen by the customers based on their actual needs. This OS needs to seamlessly integrate with existing L2/L3 topologies and support a basic set of features. Beyond this, there should be new capabilities delivered as a result of “opening up” the network switch. Also many third party provide white box switches that are already operating systems like ICOS or Cumulus while they are rolling off the production line.

white box switch

White Box Switch: What Makes It Superior over Traditional Switch

Despite the fact that the use of white box switches has been limited for a couple of reasons, such as customer worries for product quality and technical support, white box switches have come a long way from where they were. And I believe they are now ready for a broader market. I know some of you may doubt it and think it is not the one for you when buying a gigabit ethernet switch. But if you dig into it, you can see the white boxes have improved significantly in the following areas:

benefits of white box switches

1.High flexibility, as their main function is to meet the data demands.

2.These are helpful to provide efficiency and productivity to the business.

3.Lower operating cost.

4.Lower capex Methods.

5.Less costs than equivalent speed switches.

6.White box switches are open networking switches.

7.The SDN controller is accountable for centralizing the network.

8.White box switching software can be easily attainable through any reseller or partner directly.


Maybe a white box gigabit switch is not the best gigabit switch in your heart right now, it is still undeniable that white box switch will be the future trend for data center siwtches. Many mainstream networks vendors also began to provide white box switches. Also, these will come shipped with tried-and-true network operating systems from vendors such as Pica8 and Cumulus.