Anycast is the communication between a sender and the nearest group of receivers. When a unicast address is assigned to more than one interfaces, the message sent to the interfaces is routed by the network to the nearest destination interface measured by the routing protocol.
Border Gateway Protocol (BGP) is a routing protocol running on TCP for autonomous systems.
Broadcast refers to broadcasting packets in an IP subnet where all the servers in the subnet will receive these packets.
Multicast achieves a one-to-many network connection between the sender and each receiver. If the sender transfers the same data to multiple receivers at the same time, only one packet needs to be copied.
Unicast establishes an individual data channel between the client and the media server where all the packets from the server can only be sent to the client.