Global Command - Explained

A

A global command is a command that affects the entire router and is set once. This means that the command is applied to all interfaces, protocols, and services running on the router. It is a configuration command that applies to the router as a whole, rather than to a specific interface or service.

Option A is the correct answer.

Option B is incorrect because a global command is not necessarily implemented in all foreign and domestic IOS versions.

Option C is also incorrect because a global command does not necessarily support all protocols.

Option D is incorrect because a global command may not be available in every release of IOS.

Option E is incorrect because a global command is typically entered in global configuration mode, not any configuration mode.

It is important to understand the difference between global commands and interface-specific commands. Interface-specific commands only apply to the interface on which they are configured, while global commands apply to the entire router. Global commands are typically configured in global configuration mode using the "config" command. Some examples of global commands include configuring hostname, passwords, banners, and IP addresses.