Technologies for optical communication in a rack cluster in a data center are disclosed. In the illustrative embodiment, a network switch is connected to each of 1,024 sleds by an optical cable that enables communication at a rate of 200 gigabits per second. The optical cable has low loss, allowing for long cable lengths, which in turn allows for connecting to a large number of sleds. The optical cable also has a very high intrinsic bandwidth limit, allowing for the bandwidth to be upgraded without upgrading the optical infrastructure.