This value specifies which particular network performance metric -- such as one-way delay, delay variation, or packet loss, measured near-end, far-end, or two-way -- a given SLA job is actually monitoring and checking against a threshold. Administrators set this when configuring an SLA measurement job to focus it on the specific performance dimension they care about, such as round-trip packet loss for a voice service. For example, setting this to lostPktsTwoWay(9) configures the job to monitor two-way packet loss rather than delay or delay variation.