The unceasing migration to higher levels of network performance and scalability drives the boom of 100G transceiver market. 100G transceiver has become a preferable alternative for those bandwidth-hungry applications to accelerate data flow in data centers. In this article, we will introduce several types of 100G transceiver which are commonly seen on the market. And emphasis will be put on the 100G QSFP28 transceiver.
Common 100G Transceiver Decoding
Currently, we have 100G CFP transceiver, CFP2 transceiver and CFP4 transceiver available on the market. The CFP transceiver comes out firstly. It was designed just after SFP interface, but it is significantly larger to support 100 Gbit/s data rates. While the electrical connection of a CFP transceiver uses 10 x 10 Gbit/s lanes in each direction (RX, TX), the optical connection can support both 10 x 10 Gbit/s and 4 x 25 Gbit/s variants of 100 Gbit/s interconnects.
As technology keeps advancing, there came CFP2 and CFP4 that allows higher performance and density. Having similar electrical connection with a CFP transceiver, CFP2 and CFP4 transceiver specify a form-factor of 1/2 and 1/4 respectively in size of a CFP transceiver. These three modules are not interchangeable, but would be inter-operable at the optical interface with appropriate connectors.
100G QSFP28 transceiver Description
Then here comes the dominate 100G transceiver—100G QSFP28 transceiver, supporting four 25 Gbit/s lanes. With an upgraded electrical interface, 100G QSFP28 transceiver is capable of handling signal rates up to 28 Gbit/s, making 100G network deployment as easy as that of 10G. Moreover, 100G QSFP28 transceiver has a strong ability to increase density, decrease power consumption, and decrease price per bit.
Thanks to QSFP28 module, the path to 100G can hence be changed from 10G-40G-100G to 10G-25G-100G or 10G-25G-50G-100G, with largely simplified cabling and reduced costs. There are two widely used 100G QSFP28 transceiver: QSFP28 100G SR4 for short range transmission up to 100 m and QSFP28 100G LR4 for long range transmission up to 10 km. The following diagram illustrate the details of each QSFP28 module.
What to Benefit From 100G QSFP28 transceiver?
Giving a look back to the evolution of 100G transceiver, all these changes are closely related to factors like power and cost – makes the prevalence of 100G QSFP28 transceiver an inevitable trend. Then, what exactly can QSFP28 module bring to us?
Higher Port Density: The first generation of 100G transceiver is CFP, which is very large. When it comes to CFP2 and CFP4, the size was a lot decreased. With the same footprint and face plate density as QSFP+, QSFP28 module is even smaller than CFP4, and its high port density is also an overwhelming advantage. Generally, up to 36 QSFP28 can be installed on a 1RU switch on the front panel.
Lower Power Consumption: Compared with other 100G transceiver, QSFP28 transceiver requires the lowest power for transmission, with less than 3.5 Watts. While for other 100G transceiver, the power consumption ranges from 6 Watts to 24 Watts.
Lower Cost: QSFP28 transceiver is able to save considerable amount of money with higher port density and lower power consumption. While implemented with four lanes, 100G QSFP28 transceiver increases the transmission capacity of every lane from 10G to 25G, which effectively decreases the cost for each bit.
With higher port density, lower power consumption and lower cost, 100G QSFP28 transceiver offers an optimum and feasible alternative for 100G network, especially for those large scale data centers and carriers. Hope this article could assist you in choosing the right transceiver to achieve smooth 100G migration.