What is a Unique Address?
Globally unique addresses are unique across the whole internet. It can mean that just one device has an address. For instance, a device connected to a Wi-Fi network could have a unique IP address.
- Uniqueness of IP Addresses: A globally unique IP address is assigned to a single device, allowing it to communicate over the internet without conflict or duplication.
- Anycast Addressing: In contrast, anycast addressing allows multiple machines to share the same IP address. These machines are geographically distributed, and the network routes traffic to the nearest available instance, making services more efficient and resilient.
- Control Over Usage: An IP address is considered unique if a single organization controls how it is used, ensuring that the address serves a specific function or device without overlap.
But a popular service distributed across multiple machines could also use the same IP address. That’s called anycast. Sometimes these addresses are called unique service addresses.
So, an IP address is unique if one organization controls how it is used.