An Introduction to 400G Cabling Solutions!

400G a reality now! The main benefit in moving from 100G to 400G is that superior connectivity achievable between the leaf and spine. However, older form-factors are not compatible with 400G optics. Thus, new form-factors were required. Currently, there are two recognized and regularized form-factors for 400G cables and optical modules

The OSFP (Octal Small Form-factor Pluggable)

The electrical interface of a 400G OSFP connector comes with 8 x electrical lanes. Where each lane runs at 50 GB/s resulting in a total bandwidth of 400 GB/s. Because of their different size, OSFP modules are not backward compatible with the existing QSFP modules. However, backward compatibility can be achieved through OSFP to QSFP adaptors.

The QSFP-DD (Quad Small Form-factor Pluggable)

The QSFP-DD form factor is identical in size and shape to its predecessor – the QSFP form factor. However, its electrical interface comes with an additional four lanes to provide eight electrical lanes in total. Likewise, OSFP, each electrical lane of a QSFP-DD connector can operate at 50 GB/s resulting in a total bandwidth of 400 GB/s.

What are 400G Cabling Solutions available?

First of all, let us refresh our memories and go through the most common types of cabling arrangements. Please check the image below:

As you can see, there are three kinds of cabling solutions widely used in commercial networking environments. Today, a complete range of 400G Active Optical Cables and 400G Direct Attach Copper Cables are available in the market. As far as the form factor is concerned, you can source these cables in both OSFP and QSFP-DD form factors. Moreover, these cables can be acquired in different lengths.

Direct Attach OSFP & QSFP-DD Cables

Straight through Direct Attach Cables offer 400G transmission over short distances. These cables are available for both OSFP and QSFP-DD form-factors. Direct Attach OSFP & QSFP-DD Cables are designed to handle transmission as defined by 400GBASE-CR4 standard. A DAC cable comes with two copper-based conductors for the transmission of electrical signals. OSFP & QSFP-DD Cables can be used in a variety of hardware systems e.g., in servers, switches, HBA `s, etc. Following OSFP & QSFP-DD DAC cables are available from CBO:

OSFP DAC`s

QSFP-DD DAC`s

AOC OSFP and QSFP-DD

AOC OSFP and QSFP-DD cables come with transceivers at their respective ends. Whereas, a fiber cable is used for transmission of information. AOCs offer digital diagnostic monitoring. Thus, you can keep an eye on your cable`s critical parameters on a real-time basis. Moreover, active optical cables offer hot-pluggable connectivity. So, you can attach or detach these cables from an operating network safely. Active Optical OSFP and QSFP-DD Cables handle data transmission as defined by 400GBASE-SR8 standard. In comparison to the DACs, AOCs offer greater link distances. Following OSFP & QSFP-DD AOC cables are available from CBO:

OSFP AOC`s

1. BO303003X1M 1.0 Meter OSFP to OSFP AOC
2. BO303003X3M 3.0 Meter OSFP to OSFP AOC
3. BO303003X5M 5.0 Meter OSFP to OSFP AOC
4. BO303003X10M 10 Meter OSFP to OSFP AOC
5. BO303003X50M 50 Meter OSFP to OSFP AOC etc.

QSFP-DD AOC`s

1. BO292903X1M 1.0 Meter QSFP-DD to QSFP-DD AOC
2. BO292903X7M 7.0 Meter QSFP-DD to QSFP-DD AOC
3. BO292903X20M 20 Meter QSFP-DD to QSFP-DD AOC
4. BO292903X30M 30 Meter QSFP-DD to QSFP-DD AOC
5. BO292903X50M 50 Meter QSFP-DD to QSFP-DD AOC etc.

Conclusion:

Undoubtedly, 400G is going to replace the existing network technologies soon. Various vendors have already started developing specific cabling products for 400G, and their portfolios are enlarging. At CBO, we are developing fantastic 400G DAC and AOC cables. In addition to this, our breakouts cable in OSFP and QSFP-DD form-factors are creating new networking possibilities.