Packaging differences between QSFP56 and other QSFP series

In the constantly developing field of network technology, the size of the external dimensions of optical modules plays a crucial role in determining the efficiency and performance of data transmission equipment. QSFP56 is a significant advancement in this field, surpassing previous generation products as the next-generation solution. This article analyzes the subtle differences in packaging between QSFP56 and QSFP series for your reference

1, Packaging of 200G QSFP56 optical module

To clarify the packaging of QSFP56, let's first review the packaging of QSFP. QSFP, also known as Quad Small Form Factor Pluggable, is a four channel compact and pluggable upgrade to SFP optical modules, replacing single channel SFP solutions with high-density multi-channel solutions. QSFP typically integrates four wavelengths into QSFP packaged optical modules, providing four times the bandwidth capacity compared to SFP

40G QSFP+is an upgrade based on QSFP, and the subsequent 100G QSFP28 is a high-density solution based on QSFP solution. With the continuous upgrading of data traffic in data centers and advanced network applications, the market urgently needs faster choices. The subsequent 200G QSFP56 and 400G QSFP56-DD are further upgrades and iterations of the QSFP series.

As an upgraded version of its predecessor 40G QSFP+and 100G QSFP28, the four channel 50G small form factor pluggable QSFP56 is designed specifically for 200G Ethernet applications. In QSFP56, 56 represents a single channel rate of 56G, which means 4 channels are 4 * 56. For convenience, we collectively refer to it as 200G QSFP56. The size and appearance of the QSFP56 optical module are similar to those of the QSFP module. QSFP56 optical modules are classified according to transmission distance, including QSFP56 CR, SR, DR, FR, LR, etc. Each type uses multi-mode or single-mode optical fibers for transmission depending on the distance.

Two QSFP56 200G optical modules combined with a single mode or multimode fiber can establish a 200G transmission link. Alternatively, 200G QSFP56 AOC and DAC can be used for stacking. 200G QSFP56 can be branched into two 100G QSFP28 branch optical cables; 200G QSFP56 can also be branched into four 50G SFP56 branch fibers for easy aggregation of core link connections.

2, Basic parameters of QSFP56, QSFP28, and QSFP+

From their industry names, QSFP56, QSFP28, and QSFP+are very similar because they have the same QSFP basic packaging scheme and they have the same size as each other. However, their data centers and connectivity capabilities are different. The following table lists the basic parameters of QSFP56, QSFP28, and QSFP+.

With the launch of 400G QSFP-DD, which is a four channel compact and pluggable high-density device, the future network landscape will undergo significant changes. The advancement of this technology represents a significant leap in data transmission, with speeds as high as 400G per second. With the rapid growth of data centers, the demand for data volume continues to grow, driving network components to support higher bandwidth and density. The latest version of optical module packaging is from QSFP56 to QSFP56-DD, also known as 400G QSFP-DD. The DD here refers to double density, which means that by doubling the data channels of QSFP56 from 4 channels to 8 channels, it reaches 400G (using 50G PAM4). Although QSFP56-DD has double density, its size is similar to QSFP56.

The QSFP56-DD port is backward compatible with QSFP optical modules, which means that as long as the switch supports it, QSFP56 can work on the QSFP56-DD port. When using the QSFP56 module in the QSFP56-DD port, this port will be configured with a data rate of 200G instead of 400G. The QSFP56-DD external dimensions are now recognized by the 400G market as the most popular 400G external dimensions. Although 400G Ethernet is now seen as a futuristic solution for next-generation data centers, for some organizations deploying 200G Ethernet, 200G QSFP56 is still needed.