Networks, whether they are corporate intranets, wireline carrier networks, or wireless networks, are basically comprised of nodes and transmission channels. Nodes, also known as Network Elements (NEs), support a variety of communication functions, including multiplexing, switching, and routing. Many of these NEs reside at a particular layer of the Open Systems Interconnection Reference Model (OSIRM), while others support several layers of the protocol model (generally, it is more cost-effective to have an NE cover multiple layers, as compared to discrete devices; this way, there is no need for multiple chassis, multiple power supplies, multiple racks with interconnecting cables, multiple network monitoring systems, etc.). Regardless of the functional bundling, NEs are critical to the proper functioning of any network.