This read-write INTEGER describes whether Connection Admission Control functionality is applied on the VISM card on a per-PVC basis, and can be disabled card-wide for applications that don't need it. CAC prevents oversubscription of bandwidth/resources by refusing new connections once a PVC is full, so an admin disables it only when confident that application doesn't require that protection. For example, an admin running an application with its own external admission control might disable vismCacEnable to avoid CAC interfering with connections it wasn't designed to gate.