Of course, these aren't the only license types found in Symantec's products. There is also licensing per appliance, IP, node, processor, tiered NAS device, SAN switch port, storage domain, and server bundle, among others. Many of these other types are used to license component products or special products within a larger family. When unsure about a licensing metric, or researching a product, first check the product EULA. They rarely provide a complete picture, but are a good place to start. Symantec maintains a public list of current product license agreements on its website.