<Li> Certain ITU - T standards in the V series (notably V. 24 and V. 35) </Li> <Li> Certain ITU - T standards in the X series (notably X. 21 and X. 25) </Li> <P> A general rule is that DCE devices provide the clock signal (internal clocking) and the DTE device synchronizes on the provided clock (external clocking). D - sub connectors follow another rule for pin assignment . DTE devices usually transmit on pin connector number 2 and receive on pin connector number 3 . DCE devices are just the opposite: pin connector number 2 receives and pin connector number 3 transmits the signals . </P> <P> When two devices, that are both DTE or both DCE, must be connected together without a modem or a similar media translator between them, a crossover cable must be used, e.g. a null modem for RS - 232 or an Ethernet crossover cable . </P>

Is a router a dte or dce device