Morning all, I'm reading up about Ethernet networks in terms of broadcast domains and collision domains. To me this seems to be two names to describe the same thing. If I have a single network segment connected by a simple hub then quite clearly all hosts on that segment can communicate with each other directly using the MAC address and so we have by definition a broadcast domain. Now in the same segment, there is nothing then to prevent two hosts attempting to transmit at the same time thus producing a collision - in which case we also have a collision domain. I understand that when this happens, a JS or Jam Signal is sent out by the two hosts which caused the collision in order to prevent a repeat collision when the data is resent. I know that broadcast packets cannot pass through routers and so if we have a router connecting two broadcast domains, collisions can occur locally within each segment but it is not possible for collisions to occur between packets from different segments since the router is acting as a barrier. Am I right here and broadcast and collision domains basically the same thing or is there a distinction between the two?