Will QSFP28 Be a Better Way to 100G?

28 Sep 2016

The battle over 100G component market has been upgraded with the emerging of 100GBASE QSFP28 module—an optical transceiver which can support 100G with the transmission mode of 4*25G. Before its appearance, the way to move to 100G is considered to be 10G→40G→100G. However, the new 100G road map with QSFP28 is 10G→25G→100G or 10G→25G→50G→100G. Currently some data centers have already adopted this new road for 100G migration. A lot of questions pop into our brains. Why does 100G QSFP28 appear? How could 100G QSFP28 change our data center? Will this new road replace the former one? This post will offer the answers to these questions.

What Can QSFP28 Offer?

Cost and power are always the most important factors to consider in data centers, which are also the big drivers optical communication market. Giving a look back to the evolution of 100G modules in the past few years, things keep changing, from CFP to CFP2 and CFP4. Various 100G standards are also published accordingly. All these changes are closely related to the importance factors like power and cost that data center must consider about. Thus, the reasons why 100G QSFP28 emerges are partly explained.

• Higher Port Density: The first generation of 100G transceiver is CFP, which is very large. Then size of CFP2 and CFP4, the next generation of 100G modules, decreased a lot. CFP4 is a quarter width of CFP. With the same footprint and faceplate density as QSFP+, QSFP28 is even smaller than CFP4. Higher port density is a big advantage of QSFP28. Up to 36 QSFP28 can be installed on a 1RU switch on the front panel.
  
  
• Low Power Consumption: Compared with other 100G transceivers, QSFP28 needs the lowest power for transmission, which could be less than 3.5 W. While for other 100G transceivers, the power consumption ranges around 6 W to 24 W.
  
  
• Lower Cost: With higher port density and lower power consumption, the QSFP28 can save more. In addition, QSFP28, implemented with four lanes, increases the transmission capacity of every lane from 10G to 25G, which can effectively decrease cost for each bit.

How Could QSFP28 Change Data Center?

The road to 100G with QSFP28 can escape the 40G and reach 100G directly from 25G. As mentioned QSFP28 using four 25G lanes to transmit signals, which is accordance with the 100G Ethernet standards. The 100G uplink is converged by only four 25G links. In addition, the 25G network has the same cabling structure as 10G network. However, the capacity of the network much larger. Thus the 100G road map from 10G to 25G to 100G can largely simplify the cabling in data center and effective decrease the cable density and the cost. 

Will QSFP28 Replace Other Modules?

No one can tell what the future will like. Even QSFP28 has various advantages, its appearance just offers an alternative to 100G migration. The upgrade road is no longer limited to 10G-40G-100G. For data centers and server rooms, suitable is the best. Customers can select the path according to their applications. The QSFP28 family is now available in FS.COM.