Because, the higher the data rate, the more cost effective the transmission facility. That is, for a given application and over a given distance, the cost per kbps decline with an increase in the data rate of the transmission facility.
Multiplexing allows multiple users to use a single channel (frequency) for communications.
In analog transmission, signals are commonly multiplexed using frequency-division multiplexing (FDM)
Downward multiplexing refers to distributing a single signal across multiple channels.
Multiplexing techniques vary widely based on what is being multiplexed. Modern telecommunications use a very wide array of techniques including: TDM - examples: TDMA, T-carrier FDM - examples: DWDM Spatial - example: MIMO Code division - examples: CDMA Phase or polarization division - cable/satellite TV Statistcal - examples: packet mode (STS), FHSS etc etc. This is far from a complete list. I think the question needs to be more specific.
SONET uses an inverse multiplexing technique called virtual concatenation. SONET, which is the standard used in the United States and most of Europe, stands for Synchronous Optical Network.
TDM
disadvantages of wavelenth division multiplexing
http://zone.ni.com/devzone/cda/ph/p/id/269
Frequency-division multiplexing, wavelength-division multiplexing, and time-division multiplexing.
Frequency-division multiplexing and wavelength-division multiplexing
What is multiplexing and its diagram
what is function of amplitude division multiplexing
application of multiplexing in data communication
Packet switching has two advantages: (1) If something goes wrong, only a small piece of data (the packet) has to be resent. (2) Packet switching allows multiplexing - several communications happening at once.Packet switching has two advantages: (1) If something goes wrong, only a small piece of data (the packet) has to be resent. (2) Packet switching allows multiplexing - several communications happening at once.Packet switching has two advantages: (1) If something goes wrong, only a small piece of data (the packet) has to be resent. (2) Packet switching allows multiplexing - several communications happening at once.Packet switching has two advantages: (1) If something goes wrong, only a small piece of data (the packet) has to be resent. (2) Packet switching allows multiplexing - several communications happening at once.
In analog transmission, signals are commonly multiplexed using frequency-division multiplexing (FDM)
Downward multiplexing refers to distributing a single signal across multiple channels.
Space division multiplexing uses spacing to separate channels in a communications link. These separations may be done by frequency, insulation, or distance (spacing). Time division multiplexing is one way of doing the spacing separation. Space division multiplexing may use other techniques, such as TDM, FDM, etc., to maintain separation so that the conversations do not collide with each other.
Multiplexing is the process of combining multiple signals over one media line. There are several types of multiplexing: frequency division, time division, and wavelength division.