With the growing availability and prevalence of internet-capable devices, the complexity
of networks and associated connection management increases. Depending on the use case, different
approaches in handling connectivity have emerged over the years, tackling diverse challenges in
each distinct area. Exposing centralized web-services facilitates reachability; distributing information
in a peer-to-peer fashion offers availability; and segregating virtual private sub-networks promotes
confidentiality. A common challenge herein lies in connection establishment, particularly in discover ing, and securely connecting to peers. However, unifying different aspects, including the usability,
scalability, and security of this process in a single framework, remains a challenge. In this paper,
we present the Stream Exchange Protocol (SEP) collection, which provides a set of building blocks for
secure, lightweight, and decentralized connection establishment. These building blocks use unique
identities that enable both the identification and authentication of single communication partners. By
utilizing federated directories as decentralized databases, peers are able to reliably share authentic
data, such as current network locations and available endpoints. Overall, this collection of building
blocks is universally applicable, easy to use, and protected by state-of-the-art security mechanisms
by design. We demonstrate the capabilities and versatility of the SEP collection by providing three
tools that utilize our building blocks: a decentralized file sharing application, a point-to-point net work tunnel using the SEP trust model, and an application that utilizes our decentralized discovery
mechanism for authentic and asynchronous data distribution.