LLC (Link Level Control) filters can be defined on an inclusive or exclusive basis: CMs can be configured to forward only packets matching a set of layer three protocols, or to drop packets matching a set of layer three protocols. Typical use of these filters is to filter out possibly harmful (given the context of a large metropolitan LAN) protocols. If set to discard(1), any L2 packet that does not match at least one filter in the docsDevFilterLLCTable will be discarded. If set to accept(2), any L2 packet that does not match at least one filter in the docsDevFilterLLCTable will be accepted for further processing (e.g., bridging). In other words, if the packet does not match an entry in the table, it takes this action; if it does match an entry in the table, it takes the opposite of this action.