How is bandwith "created"?

Irregardless of how powerful your CPU is, or how fast your RAM is, you need bandwith to get everything to communicate. The same is true in networking. You need bandwith for each computer to communicate between each other.

Now for the question. How do you make bandwith? Why is it that you can get more bandwith out of the same cables? For example, RJ45 cables can do 10mbit, all the way up to 1000mbit in common connections. Why is it that you could have a 10mbit connection rather than a 1000mbit if you are using the same cable? I guess what I am saying is what makes it all work.

i dont know how they work

however

bandwidth=width*clock

assume each pin is 1bit, therefore with 8 pins u get 8 bits, perhaps 10mbit only uses 1 pin and 100mbit uses 10 pins, etc. or the rate at which data is sent increases, etc

You were getting there wwwwww, bandwidth=bits*clock

Your CAT5 ethernet cable is rated to 1Gbps bandwidth, but the hardware you are using may only get up to 100Mbps. In this case, the cable (or pipe) is capable of handling a higher clock speed than your current ethernet card can generate. That's not to say that any CAT5 installation would deliver 1Gbps with 1000Mb NICs installed, that is just what the cabling is rated for-- if the connectors were put on sloppiily, the cable is severely bent or damaged when installed or inappropriate hardware is used somewhere in the line, then your bandwidth can be severely reduced.

Your NIC will scale down, so if you have a 10/100 card in one computer and a vanilla 10Mbps card in the other, then both computers will communicate on a bandwidth up to 10Mbps... again dependant on the prevailing conditions in the pipe.

This is why a 56Kbps modem card rarely, if ever, hits the 53K maximum bandwidth allowed by law. Here is a more detailed explantion for that.

Some of the factors that can reduce your usable bandwidth are:

• Noise inherent in the network. Poor wiring connections or shielding can cause noise. So can "crosstalk," the effect of signals from other wires inducing noise on your wire.
• Clock speed of the transmitter/receiver. This is pretty obvious.
• Impedance. The longer the cable is, the more resistance it provides to the transmitter, which results in reduced signal strength and poor signal/noise ratio (if the signal is too small, you can't distinguish it from background noise).
• Other hardware issues. If the computer is too busy crunching numbers for your favorite graphics-intensive video game, it may not empty the buffer as quickly, so your effective bandwidth would be reduced.

Does this answer your question sufficiently?

OK, I think that I am starting to get it (thanks!) Now if I were to go a little deeper into the subject, how does the bus width work, and how do you send digital data across a line running DC voltage through it? At least I think that DC voltage runs through lines. Also, what frequencies run through your traditional RJ45 cable for 100mbit communication? Oooh, and another question, though it may be a little off topic, how do DSL connections work? It comes off of a telephone line and obviously runs to a modem which then connects to your computer. What does this modem do differently from a 56K modem to get the 8mbit connection speeds and now with ADSL 2+ 22mbit connection speeds?

Bandwidth is defined as the range of frequencies available.

DSL uses much higher frequencies than a standard phone so it has higher bandwidth. These frequencies are not used by a phone but you use a splitter to guarantee these frequencies are kept apart.

Twisted-pair cable:
This is used for telephones and LANs, but this medium is very susceptible to signal corruption due to stray external electrical signals, but is suitable for connecting devices to networks like computers and printers. It consists of two unshielded wires twisted around each other (UTP). Category 5 is the usual standard of cable used for connecting devices to networks; it consists of 4 pairs of twisted cable with RJ-45 connectors that are similar to but wider that RJ-11 connectors used for phone lines.

Coaxial Cable:
High capacity cable that is shielded and suitable for long distance connections. Thin coax cable can be used for LANs and home TV cabling.

Fibre-optic Cable:
Made of glass, very high is data-carrying capacity, suitable for very long distances and very fast with no chance of electrical interference and little chance of chemical corrosion or pest infection. Good for backbones in networks and for Internet cable connections.

Radio Waves:
This refers to wireless connections. They are multi-directional and can be interfered with easily so are currently used only for short distances.

Infrared:
Used to connect devices like computers and printers over short distances and with line of sight.

Microwave:
Is like radio but can directed over long distances but line of sight is needed between pairs of transceivers.

Satellite:
Used to transmit data over very long distances. Can be slow as the data needs to travel to a satellite and then back down to a computer.