This limits the maximum multicast bandwidth, in bytes per second, that may be delivered to a client port; a value of 0 (the recommended default) imposes no administrative limit, and G.988's bandwidth-enforcement attribute should be enabled when this is nonzero, per ITU-T G.988 9.3.28. Admins set it to cap how much of the access line's bandwidth multicast video can consume, protecting bandwidth for the subscriber's other (unicast) services. For example, capping this ensures streaming multiple HD channels doesn't starve a subscriber's regular internet traffic.