A strong demand for bandwidth is generated by the new generation of cloud apps-not only for the user, but also within the data center and between data centers. You have a lot of bandwidth when you have data centers running digital systems, not only between the clients and the data center, but also a lot of east-west traffic, i.e. you have a lot of traffic going between servers.
Server technology innovations also drive demand for bandwidth. These improvements include faster processors that can go through more data faster; smart NICs that offload work from server processors, freeing those processors for more data-intensive work; and FPGAs that enable the NIC to handle work like encryption itself.
All of these advances increase the amount of information that can be processed by the network, requiring increased bandwidth to meet that demand. The data center's bandwidth is rising meteorically. The Global Cloud Index of Cisco predicts that data center traffic will triple in 2021.
Vendors of networking are stepping up to meet this demand. We saw the first 400Gbit / s data center systems tested at the recent Optical Fiber Communications conference for up to 2 km distances based on QSFP28 modules, as well as other innovations to feed data rates of the next decade. We see solutions emerging for 600 Gbit / s and 1.2 terabits for data center interconnection. Nonetheless, bandwidth demands in optical technology lead to a revival as vendors try to fill the need.
