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Okay.

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So before we talk about how to expand the sniffing space, let me explain the act of network devices

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and the routers, hubs and switches.

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Hub is commonly used to connect segments of a LAN, which is a local area network, and a hub contains

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multiple ports.

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When a packet arrives at one port, it is copied to the other ports so that all the segments of the

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land can see all of the packets.

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Hub acts as a common connection point for devices in a network.

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Now Switch operates at the data link layer layer two and sometimes the network layer, which is layer

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three of the OSI reference model.

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And therefore support any packet protocol.

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A Lancet used switches to join segments are called switch Islands or in the case of Ethernet networks,

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switched Ethernet lens in basically all networks.

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Switch is a device that filters and forwards packets between LAN segments.

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A router is connected to at least two networks.

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Commonly two LANs or WANs, which are the wide area networks, or LAN and its ISP, which is the Internet

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Service Providers Network.

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Router is generally located at Gateways, the places where two or more networks connect.

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Using headers and forwarding tables.

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Router determines the best path for forwarding the packets, and in addition, the router also uses

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protocols such as ICMP Internet control message protocol to communicate with each other and configures

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the best route between any two hosts.

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So in a word, router forwards data packets along networks.

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Now let's compare the hub and the switch.

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Since both of these two devices have similar roles on the network.

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Each serves as a central connection for all of your network equipment and handles a data type known

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as frames.

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Frames Carry your data.

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When a frame is received, it is amplified and then transmitted on to the port of the destination PC,

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which is typically a personal computer.

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The big difference between a hub and a switch is in the method in which frames are being delivered.

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You got that in a hub.

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A frame is passed along or broadcast to every one of its ports.

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It doesn't matter that the frame is only destined for one port.

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The hub has no way of distinguishing which port a frame should be sent to.

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Right.

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So passing it along to every port ensures that it will reach its intended destination.

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Now, this places a lot of traffic on the network and can lead to poor network response times.

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You can only imagine, right?

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Besides, the frame is received by the unintended nodes, which could be hackers.

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And in a cybersecurity point of view, what about the confidentiality?

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And additionally, on a ten 100 megabit per system hub, it must share its bandwidth with each and every

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one of its ports.

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So when only one PC is broadcasting, it will have access to the maximum available bandwidth.

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However, if there are multiple PCs broadcasting, then that bandwidth will need to be divided among

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all of those systems which will degrade performance for everybody.

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So in comparison, a switch keeps a record of the Mac, which is the media access control address of

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all the devices connected to it.

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With this information, a switch can identify which system is sitting on which port.

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So when a frame is received, it knows exactly which port to be sent to without significantly increasing

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network response times.

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And in addition, unlike a hub, a ten 100 megabit per second switch will allocate a full ten 100mbps

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to each of its ports.

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So regardless of the number of PCs transmitting, users will always have access to the maximum amount

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of bandwidth.

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That's important.

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So it's for these reasons that a switch is considered to be, well, let's say, a much better choice

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than a hub, right?

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Good.