(also Class D IP)
Class D IP address is an IP address not assigned to individual hosts but rather used for multicasting. Through the use of multicasting, a single host is able to simultaneously transmit a single data stream to thousands of other servers located across the internet. IP addresses that belong to class D have the value 1110 assigned to their higher-order bits in the first octet of their addresses at all times. The remaining bits make up an address that can be recognized by any hosts interested. Streaming audio and video content is a common application for it, as seen with IP-based cable TV networks. Another illustration of this is the dissemination of real-time data on the stock market from a single source to several brokerage firms. There is no sub-net mask associated with the Class D network.