Systems and methods are provided for timing signals, measuring latency, and/or timestamping. Some of the systems described herein can measure latency in a network device, and can include a signal generator, a sampler, a pulse detector, a timer, and a connector. The signal generator can define a signal profile. The sampler can sample the signal profile at a frequency of at least 4 GHz to generate a plurality of bits, each bit corresponding to a value of the signal profile during the sampling. The pulse detector can detect a change in the signal profile by detecting at least one change in the plurality of bits. The timer can time the change in value in the plurality of bits to provide at least one detection time measurement. The connector can electronically link the signal generator and the sampler to the network device to provide an external network path for transmitting a signal from the signal generator to the sampler via the network device.