If the U/L bit of a MAC address is 0, what type of address does it designate?

When the U/L (Universal/Local) bit of a MAC address is set to 0, it indicates that the address is a Universally Administered Address (UAA). This type of address is assigned by a standards organization or manufacturer and is unique across the globally of devices.

In contrast, if the U/L bit were to be set to 1, it would signify a Locally Administered Address (LAA), which can be assigned by a network administrator for a specific network. The distinction helps devices and systems recognize whether an address is intended to be globally unique or managed locally, providing clarity in network communications and operations.

The other options, such as Shared Address and Dynamic Address, do not specifically relate to the U/L bit; rather, they pertain to different contexts of address management within networking practices. Understanding the significance of the U/L bit is crucial in grasping how MAC addressing works within networks, especially in distinguishing between universally unique identifiers and locally configured addresses.