This paper describes the subsystem design and performance of a 256 × 256-port micromechanical beam-steering optical cross-connect with 1.33-dB average loss, which can provide 238 × 238-port cross-connect with a maximum loss of less than 2 dB. This paper describes the design chosen and analyzes the tolerance ranges required to produce low loss and simulate the expected loss distribution of the fabric. The method of establishing and testing the connections is also described. The simulation is compared with the measured system, and the expected and measured static and dynamic crosstalk are compared. © 2004 IEEE.