In a hub, a frame is passed along or "broadcast" to every one of its
ports. It does not matter that the frame is destined for only one
port. The hub has no way of distinguishing which port a frame should be
sent to. Passing it along to every port ensures that it will reach its
intended destination. This places a lot of traffic on the network and
can lead to poor network response times.
Additionally, a 10/100 Mbps hub 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. If however multiple PCs are broadcasting, then that bandwidth will need to be divided amongst all of those systems which will result in performance degradation.
A switch however keeps a record of the MAC addresses of all the devices connected to its ports. With this information, a switch can identify which system is connected to a specific port. So when a frame is received, it knows exactly which port to send it to, without significantly increasing network response times. And, unlike a hub, a 10/100 Mbps switch will allocate a full 10/100 Mbps to each of its ports. Hence regardless of the number of PCs transmitting, users will always have access to the maximum amount of bandwidth.
Routers are completely different devices. Where a hub or switch is concerned with transmitting frames, a router's job, as its name implies, is to route packets to other networks until that packet ultimately reaches its destination. One of the key features of a packet is that it not only contains data but the destination address of where it is going.
A router is typically connected to at least two networks, commonly two LANs or WAN or a LAN and its ISP network. Routers are located at gateways, the places where two or more networks connect. Using headers and forwarding tables, routers determine the best path for forwarding the packets. Routers use protocols such as ICMP to communicate with each other and configure the best route between any two hosts.
Additionally, a 10/100 Mbps hub 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. If however multiple PCs are broadcasting, then that bandwidth will need to be divided amongst all of those systems which will result in performance degradation.
A switch however keeps a record of the MAC addresses of all the devices connected to its ports. With this information, a switch can identify which system is connected to a specific port. So when a frame is received, it knows exactly which port to send it to, without significantly increasing network response times. And, unlike a hub, a 10/100 Mbps switch will allocate a full 10/100 Mbps to each of its ports. Hence regardless of the number of PCs transmitting, users will always have access to the maximum amount of bandwidth.
Routers are completely different devices. Where a hub or switch is concerned with transmitting frames, a router's job, as its name implies, is to route packets to other networks until that packet ultimately reaches its destination. One of the key features of a packet is that it not only contains data but the destination address of where it is going.
A router is typically connected to at least two networks, commonly two LANs or WAN or a LAN and its ISP network. Routers are located at gateways, the places where two or more networks connect. Using headers and forwarding tables, routers determine the best path for forwarding the packets. Routers use protocols such as ICMP to communicate with each other and configure the best route between any two hosts.
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