Alan Freedman -- The Computer Language Company - Computer Desktop Encyclopedia
Computer Desktop Encyclopedia
Longest-Running Tech Reference on the Planet

A CDE Definition

You'll love The Computer Desktop Encyclopedia (CDE) for Tech Term of the Day (TTOD)

LOOK UP ANOTHER TERM


time-division multiplexing

See TDM.



TDM

(1) (Target Disk Mode) A method for transferring files between two Macs. See Target Disk Mode.

(2) (Target Display Mode) An iMac feature that enables the screen to function as an external monitor for another computer. See Target Display Mode.

(3) (Time Division Multiplexing) A technology that transmits multiple signals simultaneously over a single transmission path. Each lower-speed signal is time sliced into one high-speed transmission. In the simplest example, three incoming 1,000 bps signals (A, B and C) can be interleaved into one outgoing 3,000 bps signal as ABCABCABCABC. The receiving end divides the single stream back into its original signals.

TDM enabled the telephone companies to migrate from analog to digital on all their long distance trunks, and later to the local loops. TDM is widely used to combine multiple 64 Kbps streams into the 1.544 Mbps capacity of a T1 channel. For example, a channel bank converts 24 analog voice conversations into digital and then multiplexes them via TDM onto the T1. Contrast with FDM. See TDMA, circuit switching, channel bank and DS.








From FDM to TDM to Packet Switching
TDM has replaced FDM (frequency division multiplexing) for telco backbone networks, but packet switching is expected to become the norm for voice and data in the 21st century.






Personal Use Only

Before/After Your Search Term
BeforeAfter
TileraTime Machine
TileWorldtime-of-day clock
Tillamooktime-of-day server
timbretime out
Timbuktutime server
time base generatortime share
Time Capsuletime sharing
time clockTime Sharing Option
time codetime shifting
Time/Datetime slice

Terms By Topic
Click any of the following categories for a list of fundamental terms.
Computer Words You Gotta KnowSystem design
Job categoriesUnix/Linux
Interesting stuffPersonal computers
InternetIndustrial Automation/Process Control
Communications & networkingAssociations/Standards organizations
HistoryDesktop publishing
Audio/VideoGraphics
MainframesSecurity
ProgrammingHealthcare IT
System design