Random jitter( RJ) is jitter caused by external factors such as thermal noise or shot noise.
Random jitter propagates indefinitely, with its peaks distributed uniformly. In theory, random jitter is expressed as an RMS value, and a standard deviation is used.
When calculating the RJ peak-to-peak value, the RJ rms value is multiplied by the bit error rate. Thus, the peak value depends on the bit error rate. It is measured with the eye diagram.