This is the list of protocols supported by an adjacent system, and it may be empty. This notification-only object carries the raw protocols-supported TLV contents from an adjacent system, letting a protocol-related adjacency trap include direct evidence of exactly which network-layer protocols that neighbor claimed to support at the moment, with an empty value specifically flagging a neighbor that advertised none at all. For example, a trap tied to a protocol mismatch event showing this object empty would tell the admin the neighbor simply never sent a protocols-supported TLV, rather than sending one that conflicted with the local configuration.