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In the last lecture, we talk about a hub which basically connects to different networks segments together,



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but I also told you that Hub is a non intelligence device, which means it transfers segments, packets



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to all other devices in this lecture.



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We're going to talk about a bridge, a bridge specifically.



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A transparent bridge is a network device that connects to similar network segments.



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Together, its primary function is to keep traffic separated on either side of the bridge, breaking



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up the collision domains, as you can see on the screen.



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No, on the screen you can see that like the example of Unguessed, so you can clearly see a laser pointer.



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Yes.



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So now this segment is now suppose this laptop wants to communicate with this PC.



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So if it was a hub here, this laptop would send a packet to this hub and unnecessarily Hub would transmit



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the packet to this PC to speak to this person to everyone.



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So what a bridge does is basically it separates this traffic from this traffic.



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So you don't need to actually send each and every package to every other device.



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Then transmission is allowed to pass through the bridge only if it is intended for the opposite side.



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For example, if this PC wants to send the packet to this PC, then only the bridge will allow the packet



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to pass.



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And that is why sometimes some network professionals also call Bridge as an intelligent hub.



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Basically, it is transmitting the packet to and through the network.



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It is the same function as the hub.



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But in this case, a bridge is using its mechanism to actually see if that packet is really intended



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for the opposite side of the network.



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It just doesn't keep on transmitting random packets to each and every receiver now, but it uses mackerels



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to make forwarding decisions and hence bridge is considered as a layer to device.



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Now bridge and switch are almost similar and the term projects which are often used interchangeably



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because the two devices are mostly use of bridging technologies, the past is there for a reason.



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You'd be hard pressed to buy a bridge today.



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So keep buying bridge, but make sure that you clearly understand the difference between bridge hub



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and a switch.



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It is really very important that you understand all these differences.