Emerging coherent pluggable optics based on 400ZR and 400G ZR+ form factors are set to make a significant impact on optical networks well into the next decade.  Pluggable coherent optics with their price and density expectations enable many new coherent applications including data center interconnect (DCI) and metro/regional/aggregation networks.   

Looking at the 400G coherent pluggables revolution primarily from the perspective of communications service providers (CSPs), this paper examines how the coherent optical market has diverged into two distinct segments focused on:

1. Highest performance capacity and reach (typically embedded)

2. Pluggability with a small footprint, low power, and low cost

On the road from 100G to 800G, coherent module development began diverging at 200G when both higher performance embedded and lower power pluggable options became available.  When the Optical Internetworking Forum (OIF) published the 400ZR implementation agreement in March 2020, this marked an even bigger milestone in the progressive bifurcation of the coherent market.  Form factors such as QSFP-DD and OSFP with OIF standardization enable interoperability and can be installed directly into a router or switch in a data center.  Among other advantages, this form factor revolutionizes IP over DWDM (IPoDWDM) by eliminating the previous footprint penalty of DWDM optics that have historically been ~2x larger than client optics. 

To learn more about how 400ZR is soon to be the highest volume coherent interface in history download your copy of The Rise of Coherent 400G Pluggable Optics today!