Some users have recently seen a message that the article to buy according to our networking products, businesses that have switches and hubs, switches more expensive, cheaper hubs, then the two products because they do not know what difference, it is feared by business fraud, they can not make a decision.
For this problem, we will for everyone from the technical and practical aspects on analysis of the low-end switches (in the high-end switches for large-scale professional networking) and the hub of the differences:
Start with the technical analysis:
We now use the methods of work adopted Ethernet is CSMA / CD (Carrier Sense Multiple Access / Collision Detection), the sender, it sends a data message for each, the first monitor on the network, when it detects line just free, they immediately send data, or to continue testing until the line is idle and then send. For the receiver, the received signal first to confirm, if it is issued to own the reception, otherwise ignore. Thus, the data transmission network exists to share and exchange these two concepts - shared management of the network is a non-working state to ease the disorder, each client will be possible to seize the communication channel, so a few clients the time to seize the channel with the formation of network congestion on the situation, when the data and the number of users exceeds a certain limit, they will cause the network performance of a deep recession. The switching network is to avoid the lack of shared networks, the role of the exchange of technology transfer is based on the packet destination address, independently of each packet sent to destination port from the port to avoid collision with other ports, increase the actual throughput of the network.
Shared Ethernet, the main problems is that all users share the bandwidth, the actual available bandwidth for each user with the network reduced the number of users increases. This is because when information is busy, the number of users may be linked into the "race" a channel and a channel at a time occupied only allow one user, so a lot of regular monitoring of wait state is a result, the signal transmission produce jitter, stagnation or distortion, seriously affected the performance of the network. Switched Ethernet, the switch supplies the user-specific information for each channel, unless both the source port information while trying to send to the same destination port, or each individual source port and destination port for communication between not occur simultaneously conflict.
Therefore, the hub is a shared work with the state of the equipment, since it is relatively easy to implement, so the prices are cheaper hubs, of course, deficiencies in speed will be difficult to avoid; while the switch is using switched technology, equipment, technical content higher than the hub, of course, also more expensive the price, but the switch can overcome the shortcomings of network congestion.
To sum up so to speak:
All ports on the hub of a shared channel contention bandwidth, so as to increase the number of network nodes, data traffic increases, the available bandwidth per node will be reduced. Hub in the form of transfer data by radio to all its ports to transmit data.
All ports on the switch are exclusive channel bandwidth to each port to ensure fast and efficient data transfer. Switch is to provide users with exclusive, point to point connection, the packets are only sent to the destination port, and will not send to all ports.
Hub is a shared device, itself can not identify the destination address, of that same period of a host to a web host to send data O'clock b Packets Yi hub Wei structure of the network in Guangbofangshi Chuan Shu, You each terminal by Taiwan Verify header information to determine whether the address to receive the same time the network can only transmit a data frame of the communication. This means shared bandwidth.
Switch based on mac address recognition, to complete the package forwarding data-enabled devices. Switches can learn mac address on the internal address table, the data frame through the origin and the recipient of the switching path between the interim, the data from the source address to destination address.
After reading the above, we should understand why some businesses will directly tell you "faster switches, hubs slow" (the argument is easy to understand it).
Let us go from the application of:
As the hub can not overcome a large amount of data and multi-user when the plug issue, so it can not connect too many clients at the same time we typically see in the market, many dozens of pieces of the hub are five of the ( previous 16 Internet cafe hub is also very popular, but now have been replaced by a switch), and only 10M; the switch 5 or 8 have (24 in all, but home prices are more expensive and really nothing necessary ), 10/100M speed are basically adaptive.
So after you see the article inside another switch or hub that can be used, then the best choice switch it, although a little expensive, but it is really easy to use than many of the hub.
