‫OK, so before we talk about how to expand the sniffing space, let me explain the active network devices
‫and the routers, hubs and switches.
‫Hub is commonly used to connect segments of a land, which is a local area network and a hub contains
‫multiple ports.
‫When a packet arrives at one port, it is copied to the other port so that all the segments of the land
‫can see all of the packets.
‫Hub act as a common connection point for devices in a network.
‫Now, Switch operates at the data link layer layer two and sometimes the network layer, which is layer
‫three of the OCI reference model.
‫And therefore support any package protocol.
‫Lands it use switches to join segments are called Switch Lands or, in the case of Ethernet networks,
‫switched Ethernet lands in basically all networks.
‫Switch is a device that filters and forwards packets between land segments.
‫A router is connected to at least two networks, commonly to LANs or Wens, which are the Wide Area
‫Network or LAN and its ISP, which is the internet service providers network.
‫Router is generally located at gateways.
‫The places where two or more networks connect.
‫Using headers and forwarding tables, router determines the best path for forwarding the packet.
‫And in addition, the router also uses protocols such as ICMP Internet Control Message Protocol to communicate
‫with each other and configures the best route between any two hosts.
‫So, in a word, router forwards data packets along networks.
‫Now, let's compare the hub and the switch, since both of these two devices have similar roles on the
‫network.
‫Each serves as a central connection for all of your network equipment and handles a data type known
‫as frames.
‫Frames carry your data.
‫When a frame is received, it is amplified and then transmitted onto the port of the destination PC,
‫which is typically a personal computer.
‫The big difference between a hub and a switch is in the method in which frames are being delivered.
‫Got that in a hub?
‫A frame is passed along or broadcast to every one of its ports.
‫It doesn't matter that the frame is only destined for one port.
‫The hub has no way of distinguishing which port a frame should be sent to, right?
‫So passing it along to every port ensures that it will reach its intended destination.
‫Now this places a lot of traffic on the network and can lead to poor network response times.
‫You can only imagine right beside the frame is received by the unintended nodes, which could be hackers.
‫And in a cybersecurity point of view, what about the confidentiality?
‫And additionally, on a 10 100 megabit per system hub, it must share its bandwidth with each and every
‫one of its ports.
‫So when only one PC is broadcasting, it will have access to the maximum available bandwidth.
‫However, if there are multiple pieces broadcasting, then that bandwidth will need to be divided among
‫all of those systems, which will degrade performance for everybody.
‫So in comparison, a switch keeps a record of the Mac, which is the media access control address of
‫all the devices connected to it with this information.
‫A switch can identify which system is sitting on which port.
‫So when a frame is received, it knows exactly which port to be sent to without significantly increasing
‫network response times.
‫And in addition, unlike a hub, a 10 100 megabits per second switch will allocate a full 10 100 megabits
‫per second to each of its ports.
‫So regardless of the number of pieces transmitting, users will always have access to the maximum amount
‫of bandwidth.
‫That's important.
‫So it's for these reasons that a switch is considered to be, well, let's say, a much better choice
‫than a hub, right?
‫Good.