Serial - Data Terminal Equipment(DTE)

DTE stands for Data Terminal Equipment. This term is used to describe devices that are at the end of a communication line and are responsible for generating and receiving data. DTE devices are typically user-end devices that communicate with DCEs, which are intermediary devices that facilitate the data transfer over the network.

Here’s a more detailed explanation:

  1. Role in Communication:

    • DTE (Data Terminal Equipment): These devices are typically located on the user end of the communication link and are responsible for sending and receiving data. Examples include computers, routers, and terminals.
    • DCE (Data Communication Equipment): These devices are typically located in between the DTE devices and are responsible for providing a path for the data. Examples include modems, switches, and CSU/DSUs (Channel Service Units/Data Service Units).
  2. Physical Layer Connection:

    • In a serial communication setup, the DTE device connects to a DCE device to establish a communication link. On a Cisco router, this usually involves a serial interface where the router (as a DTE) connects to a CSU/DSU or modem (as a DCE).
  3. Clocking:

    • The DCE device provides the clocking signal to control the timing of the data transmission. The DTE device uses this clocking signal to synchronize its data transmission. In a typical setup, the DCE device dictates the speed and timing, while the DTE device adjusts accordingly.
  4. Serial Cables and Connectors:

    • The type of cable and connector used depends on the serial interface. Common connectors include DB-25 and DB-9 for DTE devices. For example, when setting up a WAN link, you might use a V.35 cable where the router (DTE) connects to a CSU/DSU (DCE).
  5. Configuration on Cisco Routers:

    • On a Cisco router, the serial interface can be configured to specify whether it should operate as a DTE or DCE. This is done using commands in the router’s IOS (Internetwork Operating System). For example:
      Router(config-if)# clock rate 64000
      This command sets the clock rate on a serial interface, effectively designating the router as a DCE device for that interface.

In summary, in the context of a Cisco router, DTE refers to the end device (like the router itself) that generates and receives data in a serial communication setup. It connects to a DCE device, which manages the data transmission path and provides the necessary clocking signals.

Links:

https://forum.networklessons.com/t/eigrp-static-neighbor/1244/32?u=lagapidis

https://networklessons.com/cisco/ccna-routing-switching-icnd1-100-105/cisco-ios-router-basic-configuration#Interfaces