This read-create value, either -1 or 1 to 131072, specifies the maximum burst size, in kilobytes, of buffer space allowed for a queue under this multipoint bandwidth policy. An admin sets this ceiling to bound how much a queue can burst above its committed rate before excess traffic is dropped, distinct from the smaller committed burst size, Cbs. For example, setting tSASMpBwPlcyMbs to 512 allows the queue to briefly buffer up to 512 KB during a burst of multipoint traffic before further packets are discarded.