The software-defined tunnelling capabilities of Dull let two separate organisations manage their resources completely independantly, but still interconnect.
The public internet itself operates as distributed parts that cooperate together. With Dull, each vendor has control over what tunnels are published or consumed, and the same is true for customers. There is no central authority, everyone has self-soverienty.
From the perspective of a customer, they might work with several external vendors, each with several staff with varying access needs. This single customer might even excercise full control over what services are published to each staff of each vendor.
From the perspective of a support staff in a company that contracts for many customers, they have full seamless access to remote endpoints for a range of customers. That support staff doesn't need to have access to anything more than their job requires.
Altogether multiple customers working with multiple suppliers is a decentralised graph of interconnections.