|  | 6.2 | Router Configuration Modes
| 6.2.2 | Global configuration modes
Global configuration commands apply to features that affect the system as a whole. You use the privileged EXEC command configure to enter global configuration mode. When you enter this command, the EXEC prompts you for the source of the configuration commands. You can then specify the terminal, NVRAM, or a file stored on a network server as the source. The default is to type in commands from the terminal console. Pressing the return key begins this configuration method. Commands to enable a particular routing or interface function begin with global configuration commands: To configure a routing protocol (indicated by the prompt config-router) you first enter a global router protocol command type. To configure an interface (indicated by the prompt config-if) you first enter the global interface type and number command. After entering commands in any of these modes, you finish with the command exit.