Understanding of hub shared broadband and switch exclusive broadband

Because the hub itself cannot identify the destination address, when host A transmits data to host B in the same LAN, the data packet is transmitted in broadcast mode on the network with the hub as the architecture. In other words, in this way of working, only one set of data frames can be transmitted on the network at a time, and if a collision occurs, it has to be retried. This is done by sharing network bandwidth.

Switches, on the other hand, have a very high-bandwidth back bus and an internal fabric. All ports of the switch are attached to this back bus, and after the control circuit receives the packet, the processing port will look up the address comparison table in memory to determine which port the NIC (network card) of the destination MAC (hardware address of the network card) is attached to, and quickly transmit the packet to the destination port through the internal fabric, and broadcast to all ports if the destination MAC does not exist.

The switch can transfer data between multiple port pairs at the same time. Each port can be treated as an independent network segment, and the network devices connected to it enjoy all the bandwidth on its own, without competing with other devices. When node A sends data to node D, node B can send data to node C at the same time, and both transmissions enjoy the full bandwidth of the network and have their own virtual connections.

I don't know if that can help you :

Theoretically, for example, a network with a 10MB bandwidth and a hub with two hosts. This connection only has 5MB of bandwidth per host, compared to 10MB per switch (20MB per host in full-duplex mode).

Because the hub is a physical layer device, it can only work in half-duplex mode, while the switch is a device at the data link layer, which is working in full-duplex mode.

Half-duplex is like a walkie-talkie, the speaking party can't listen at this time, full-duplex is like **, speaking and listening can be done at the same time.

The phrase "hubs share bandwidth, and switch ports share exclusive bandwidth" should be understood as follows:

The theoretical limit of 10m broadband is indeed 10m, for the same 10m network cable, no matter what kind of equipment is used, the 10m broadband is shared, so the speed is impossible to break through the limit, and there is no difference between the switch and the hub for occupying the bandwidth of the network cable.

The difference is the efficiency of data transmission at the user end connected to the switch and hub, i.e., the efficiency of local data transmission.

Because the hub is a single bus structure, all user ports share 10M broadband traffic, and no CRC (cyclic redundancy code check) is performed, and one of them occupies more broadband traffic, regardless of normal or abnormal, the other people occupy less broadband traffic.

The switch is to exchange data in the mode of storage, because it is necessary to store all the data packets on the input port first, and then perform CRC (cyclic redundancy code check) check, and then take out the destination address of the packet after processing the error packet, and convert it into the output port through the lookup table to send the packet. Because of this, the storage mode has a large delay in data processing, which is its disadvantage, but it can error detect the data packets entering the switch and effectively improve the network performance. Theoretically, each port has an exclusive bandwidth of 10M, so when the local data transfer is large, the efficiency of using the switch will be much faster than that of the hub!

Much more efficient! So hubs share bandwidth, switch ports share bandwidth, and the phrase refers to different ways of local data transmission!

In terms of bandwidth, the use of switches or hubs does not affect the broadband speed; And not all the time it is better to use a switch than a hub, and only when there is frequent data exchange on the intranet of the local area network, the advantages of the switch will be reflected!

For example, a 10BaseT hub with N port has a total transmission bandwidth of 10 Mbit/s, and the average bandwidth allocated to each port is 10 Mbit/s N. If the bandwidth of each port is 10 Mbit/s, the total transmission bandwidth of the switch can reach 10 Mbit/s.

In your example, a hub goes without saying, a switch with a few ports is equivalent to a few roads that can pass through 10 cars, while the hub always has only one.

I don't know if you understand this explanation.

You can understand it this way. But the switch can be driven by ten cars at the same time, and the hub can only come one by one. Understood this way.

To put it bluntly, a hub is a function of one = a purely physical breakout that has an impact between the individual ports.

The individual ports of the switch are relatively independent.

In fact, your problem is mainly the manifestation of the difference in the way of working, from the perspective of the way of working, the hub is a broadcast mode, that is to say, when a certain port of the hub is working, all other ports have names to listen to information, which is prone to broadcast storms. When the network is large, the network performance will be greatly affected, so how to avoid this phenomenon? The switch can play this role, when the switch is working, only the port that makes the request and the destination port respond to each other without affecting the other ports, then the switch can isolate the collision domain and effectively suppress the generation of broadcast storms.

From the perspective of bandwidth, no matter how many ports the hub has, all ports share a bandwidth, and only two ports can transmit data at the same time, and the other ports can only wait; At the same time, the hub can only work in half-duplex mode. For switches, each port has an exclusive bandwidth, when two ports work, it does not affect the work of other ports, and the switch can work in both half-duplex mode and full-duplex mode.

hub on the line about 50 yuan.

One computer does **, and the other can access the Internet.

If it's just two machines, it's okay to buy a network card.

With dual network card connection, one network card is connected to the external network, and one is connected to the other machine switch is a little more expensive, and two computers are not necessary.

Router? Not to mention it.

Hub,I rarely use it.,I've only used it in the middle school computer room.,In the company, it's all about routing + switch.,You asked.,Dude is a little unclear,

The hub is the hub, it divides the bandwidth equally, that is, you have 4 ports, 100M down from above, 2 in use is 50M each, and 4 in use is 25M each.

In the case of the switch, it is full-duplex, that is, the top down is 100M, then the transmission rate of each port is 100M uplink + 100M downlink, which is theoretically 200M transceiver speed. Each port does not affect each other.