What if we have routers or hosts connected via ATM, Frame Relay, or SONET; that is, what if we have IP over SONET, IP over ATM, IP over Frame Relay, etc., do we still have broadcast domains and collision domains?

If yes, can we say that the idea of broadcast/collision domain is a consequence of the Internet Protocol?

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Broadcast domains and collision domains are almost entirely different things although they often share the some boundary (or used to).

A broadcast domain is the reach within a point-to-multipoint network - equivalent to the group of nodes that can talk to each other directly. On Ethernet, a broadcast domain is the same as a LAN segment or a VLAN. It is a concept rooted in the data link layer (L2). A broadcast domain crosses repeaters, hubs and switches, but it stops on a routed port.

All MAC-based data link layers (or similar) form broadcast domains (if they do support broadcasts).

A collision domain is formed by nodes using a shared medium that requires arbitration and can only be used in half-duplex mode. Since it's about media access, a collision domain is a physical layer (L1) concept. A collision domain crosses repeaters and hubs, and it ends on a switched port.

With modern Ethernet that is obsolete. Collison domains existed in 10BASE5 and 10BASE2 networks, and in all 10/100 Mbit/s networks that used repeater hubs - very popular in the 10 Mbit/s era, less so with 100 Mbit/s, obsolete with Gigabit upwards.

Since ATM, Frame Relay, SONET don't use shared media, there can be no collisions and no collision domain concept.

Shared-medium networks are still around, mostly wireless ones like Wi-fi and Bluetooth.

The Internet Protocol is something completely different yet again. It's a network-layer protocol (L3) that uses the layers below but doesn't care how they do their job.

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