This is the Severely Errored Seconds count reported back by the remote terminal for the currently-accumulating 15-minute window, again derived from far-end block error indications rather than a local measurement. A far-end SES spike without a matching near-end SES spike tells an admin the degradation is specific to the direction traveling toward the remote site, which narrows troubleshooting to this box's transmitter, the specific fiber strand carrying the outbound signal, or the remote receiver. A reading of 5 far-end SESs against this path's shared SES threshold of 3 (the same threshold applies to both directions per the MIB) would already be enough to trigger a statistical alarm on the far-end side alone.