2.1 DCE and DTE

Data Communications Equipment (DCE) can be classified as equipment that transmits or receives analogue or digital signals through a network. DCE work at the physical layer of the OSI model taking data generated by Data Terminal Equipment (DTE) and converting it into a signal that can then be transmitted over a communications link. A common DCE example is a modem which works as a translator of digital and analogue signals.

DCE may also be responsible for providing timing over a serial link. In a complex network which uses directly connected routers to provide serial links, one serial interface of each connection must be configured with a clock rate to provide synchronisation.

Other common DCE examples include:

  • ISDN adapters
  • Satellites (including base stations)
  • Microwave stations
  • NIC (network interface cards)
  • DCE is sometimes said to stand for Data Circuit-terminating Equipment.

Data Terminal Equipment (DTE) is any equipment that is either a source or destination for digital data. DTE do not generally communicate with each other to do so they need to use DCE to carry out the communication. DTE does not need to know how data is sent or received; the communications details are left to the DCE. A typical example of DTE is a computer.

Other common DTE examples include:

  • Printers
  • File and application servers
  • PCs
  • Dumb Terminals
  • Routers

Next: Transmission Modes