There’s been much talk of AAA and so little of RADIUS. This is largely because RADIUS will not be eternally the access control protocol of choice. In fact, RADIUS was created by a separate working group long before the AAA design and fundamentals were brought to existence. The similarities are, however, remarkable.
AAA is the foundation of the next generation remote access protocol. Developments in creating the next protocol are being made as I write this, so the days of RADIUS being the standard aren’t infinite. But on the same token, RADIUS has an established and well-respected presence in the industry, so it has a definite future.