Arista Networks, Inc.
System and method of de-skewing electrical signals

Abstract:

A method and apparatus of a device that determines transmit and receive skew times between pairs of lanes of an electrical interface of a network element is described. In an exemplary embodiment, the device couple an optical loopback to transmit and receive interfaces of an optical interface, the optical loopback capable of transporting a first optical signal with a plurality of polarization and quadrature combinations. In addition, the device determines the receive skew time by transmitting a second optical signal on the optical loopback with one of the plurality of polarization and quadrature combinations. Furthermore, the device determines the transmit skew time by, tuning transmission delays on the transmit interface for a third optical signal with components corresponding to a pair of the plurality of polarization and quadrature combinations such that the third optical signal is recoverable on the receive interface.