Issue link: https://www.e-digitaleditions.com/i/1386104
8 I ICT TODAY Although introduced by manufacturers in late 2018 and early 2019, 400 Gb/s switch options entered the market fairly recently, and significant adoption of these new switches really took off in 2020. The new 400 Gb/s switches, based on 12.8 Tb/s chips, provide much faster speeds and greater network density. The ability for switches to enable high density breakout scenarios with 100 Gb/s ports translates into a lower total cost of ownership per port. While new 400 Gb/s switches come at a significant cost, they will also likely drop in price as early adopters in the cloud service provider and telecom industries purchase more 400 Gb/s switches over the next several years. Major cloud providers, such as Amazon Web Services (AWS), Microsoft Azure, Google, and IBM, continue to gobble up more of the data center space. While cloud providers continued to strengthen their services in 2020, enterprise investment continued to shift away from their own data centers. In the third quarter of 2020, enterprise spending on data center infrastructure dropped 8 percent from Q3 2019 with three consecutive quarters of decline during the pandemic. During the same time, "enterprise spending on cloud infrastructure services reached $65 billion in the third quarter, up 28 percent from the third quarter of 2019." 1 This trajectory is not likely to change for enter- prises. In fact, half of all workloads will be run outside of the enterprise data center by 2021, either in cloud or non-cloud data centers or at the network edge, according to the 2020 updated Cisco Annual Internet Report (2018–2023). These data centers are moving to 100, 200, and 400 Gb/s uplinks now and in the near future. NEW DATA CENTER NETWORKS STANDARDS With data center demands changing rapidly, the latest transceiver technology will often reach the market before standards bodies can address them. As part of next generation tech refreshes, many of the cloud providers have requirements for distance, cost, and custom solutions that simply do not fit into standard specifi- cations. They will often adopt network technology developed through multisource agreements (MSAs) between transceiver and switch manufacturers. However, there are currently some important standards in development by IEEE that provide data centers more options for 100 to 400 Gb/s over singlemode and multimode optics, including: • IEEE P802.3db 100 Gb/s, 200 Gb/s, and 400 Gb/s Short Reach Fiber This project supports 100 Gb/s, 200 Gb/s, and 400 Gb/s optical interfaces for server attachment and other intra-data center applications using 100 Gb/s signaling over optical fiber. The project objectives include a reach of 50 meters (≈164 ft) over multimode fiber using 1 pair (100 Gb/s), 2 pairs (200 Gb/s) or 4 pairs (400 Gb/s). Target publication date for this is late 2022. • IEEE P802.3cu 100 Gb/s and 400 Gb/s over Singlemode Fiber at 100 Gb/s per Wavelength This standard supports 100 Gb/s (single wavelength) or 400 Gb/s (4 wavelength) operations over single- mode optical fiber for distances up to 10 kilometers (≈6.2 mi). Four new physical layer specifications include 100GBASE-FR1 up to at least 2 kilometers (≈1.2 mi), 100GBASE-LR1 up to at least 10 kilometers (≈6.2 mi), 400GBASE-FR4 up to at least 2 kilometers (≈1.2 mi), and 400GBASE-LR4-6 up to at least 6 kilometers (≈3.7 mi). The standard was approved in February 2021. • IEEE P802.3ct 100 Gb/s over DWDM and IEEE P802.3cw 400 Gb/s over DWDM Systems There are two separate standards in development that define transmission over a single wavelength using dense wavelength division multiplexing (DWDM) systems. IEEE P802.3ct supports 100 Gb/s operation on a single wavelength capable of at least 80 kilometers (≈49.7 mi) over a DWDM system. The target publication date is September 2021. IEEE P802.3cw 400 Gb/s over DWDM systems operates on a single wavelength capable of at least 80 kilometers (≈49.7 mi) over a DWDM system. Because the 400 Gb/s work will draw heavily from the 100 Gb/s work, 802.3ct must be technically stable before a draft of 802.3cw can circulate. Although no timeline has been officially adopted, the current estimated publication date is June 2022.