Ethernet is a Layer 2 technology that operates in a shared bus topology. Ethernet supports broadcast transmission, uses best-effort delivery, and has distributed access control. Ethernet is a point-to-multipoint technology.
In a shared bus topology, all devices connect to a single, shared physical link through which all data transmissions are sent. All traffic is broadcast, so that all devices within the topology receive every transmission. The devices within a single Ethernet topology make up a broadcast domain.
Ethernet uses best-effort delivery to broadcast traffic. The physical hardware provides no information to the sender about whether the traffic was received. If the receiving host is offline, traffic to the host is lost. Although the Ethernet data link protocol does not inform the sender about lost packets, higher-layer protocols like TCP/IP might provide this type of notification.
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