2006-08-27 17:31:55 · 5 answers · asked by Anonymous in Computers & Internet ➔ Computer Networking
Bandwidth is the data transmission capability of a particular physical device of configuration of devices. It can be measures in bits per second or bytes per second. One Ethernet standard called 10baseT provides up to 10 megabits per second in bandwidth. This is rarely achieved because of contention overhead as you add more and more computers on the network.
A hub simply takes data from one port and repeats it to all other ports. This does nothing to reduce contention overhead. In fact it tends to increase it.
A switch learns what addresses are located on each port and takes data from one port and repeats it only to the port with the computer to which the message is addressed. This reduces traffic and contention overhead on all the ports that are not sending or receiving for that particular address.
Contention overhead - Ethernet is a CDMA protocol. Collision Detection Multiple Access means that when a computerwants to send, it first listens to see if there is activity on the line. If no activity, then it sends, but it also checks to be sure that it is not sending at the same time as someone else - a collision. If it detetects a collision, it wait a few milliseconds and tries again. The more computers on a network of this sort, the greater probability of a collision and re-send - more contention overhead, less throughput, and less effective bandwidth.
2006-08-27 17:53:40 · answer #1 · answered by Hums2oldies 3 · 0⤊ 0⤋
Hub: A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.
Switch: In telecommunications, a switch is a network device that selects a path or circuit for sending a unit of data to its next destination. A switch may also include the function of the router, a device or program that can determine the route and specifically what adjacent network point the data should be sent to.
Bandwidth: A measure of the capacity of a communications channel. The higher a channel's bandwidth, the more information it can carry.
So, a hub will relay all communications/downloads/webpages to all computers connected to it, making it quite useless and bogging down networks. Switch separate the information and send it to the computer that requested it, making it more efficient.
2006-08-28 00:38:29 · answer #2 · answered by boy_icarus 2 · 0⤊ 0⤋
An Ethernet hub or concentrator is a device for connecting multiple twisted pair or fiber optic Ethernet devices together, making them act as a single segment. It works at the physical layer of the OSI model, repeating the signal that comes into one port out each of the other ports. If a signal comes into two ports at the same time a collision occurs, so every attached device shares the same collision domain.
Switch is a device for making or breaking an electric circuit, or for selecting between multiple circuits.
Bandwith : The information-carrying capacity of a network or connection.
2006-08-28 00:36:25 · answer #3 · answered by sammy_chn 4 · 0⤊ 0⤋
bandwidth is the space that you use for your site usally you get an allowence of bandwidth every month (spend it wisely)
2006-08-28 00:34:33 · answer #4 · answered by moon 111 2 · 0⤊ 0⤋
not techie answer:
hub = dumb - cheap - no options
switch = smart - more expensive - many configuration options
bandwidth: speed of a connection
higher = faster
2006-08-28 01:15:03 · answer #5 · answered by Stanley 3 · 0⤊ 0⤋