Issue link: https://www.e-digitaleditions.com/i/1386104
14 I ICT TODAY LC-LC Patch Cord LC-LC Patch Cord CABLING STRATEGIES FOR 200 AND 400 Gb/s With so many transceiver options for both singlemode and multimode, it is necessary to plan for a cabling design that can handle multiple tech refreshes, meet current bandwidth requirements, and also provide the flexibility needed to meet future network demands, including 100G, 400G, and beyond. There are numerous design factors that shape the makeup of a cabling infrastructure for 200 and 400 Gb/s networks. These may include whether the data center is an enterprise or cloud provider. In the majority of cases, it will most likely be a cloud provider moving to 400 Gb/s. Other factors include reach requirements, existing server speeds, the cost per channel, and power levels. For 400 gigabit optics, power levels are in the 10 to12 watt range, which is approximately three times that of 100 gigabit optics. Channel insertion loss budgets are an important consideration as well. The typical singlemode budget is between 3.0 to 4.0 dB, while the typical OM4 budget remains at 1.9 dB. For power and other important cabling infrastructure standards and best practices, follow ANSI/BICSI 002-2019, Data Center Design and Implementation Best Practices. For switch-to-switch cabling scenarios, a 2-fiber singlemode channel is shown in Figure 6 that delivers 400 Gb/s in the form of 400GBASE-FR4, using QSFP-DD or OSFP form factors. This is a very versatile cabling design because it can also support 10, 40, 100, and 200 Gb/s using the same 24-fiber MPO backbone cabling. FIGURE 7: 400G switch-to-switch use case with 8-fiber singlemode configuration (10/40/100/200/400G) using 400GBASE-DR4/XDR4. FIGURE 6: 400G switch-to-switch use case for 2-fiber singlemode configuration (10/40/100/200/400G) using 400GBASE-FR4. The configuration in Figure 7 can also use the same cabling to support 10 through 400 Gb/s over singlemode, supporting 400GBASE-DR4 (IEEE 802.3bs) or 400G-XDR4 (extended reach per Cisco, Arista, and Juniper Networks). This configuration delivers 400 Gb/s over four fiber pairs using short wavelength multiplexing. Once again, the 24-fiber backbone connections are present and use conversion cassettes to break into 8-fiber array cords to the transceivers. This approach allows for 100% fiber utilization. For 400 gigabit optics, power levels are in the 10 to 12 watt range, approximately three times that of 100 gigabit optics. QSFP-DD/OSFP 400G QSFP-DD/OSFP 400G QSFP-DD/OSFP 400G MPO-LC Cassette MPO-LC Cassette Base24 MPO Trunk MPO-MPO Cassette MPO-MPO Cassette 8F MPO Array Cord 8F MPO Array Cord Base24 MPO Trunk QSFP-DD/OSFP 400G