DCE (Data Communications Equipment)

The DCE provides a physical connection to the network, forwards traffic, and provides a clocking signal used to synchronize data transmission between DCE and DTE devices. 

The DCE cable has a female connector and the DTE has a male connector, so they can connected.

This type of connection between two routers sometimes is called back-to-back serial connection. 

The router with the DCE cable in it can be configured to provide clocking. 

Modems are example of DCE.