Chapter 24 · ACN 247 manage connections and it also might delay an individual packet to pack it properly onto a stream. Ethernet IEEE 802.3, commonly known as Ethernet, is likely going to be ACN's main physical net- work. More details can be found in Chapter 20, on page 189. P ROTOCOL S TRUCTURE The ACN protocols work together in a layered approach; here is a simplified structure: Component (console or target device) Component IDentifier (CID) Device Description Language (DDL) Device Management Protocol (DMP) Session Data Transport (SDT) User Datagram Protocol (UDP) Internet Protocol (IP)