In politics, a federation is a union of states (or other entities) that are partially self-governing and independent but have transferred a set of responsibilities and duties to a central government that unites them.
What’s a federated network, then? Alternative social networks such as Diaspora and Lorea have been described as adopting a federated structure, but their server architecture is often strongly reminiscent of [Paul] Baran’s description of a decentralized system. In Diaspora, for example, users become a member of a “pod,” and in principle only connect directly with their own pod; these pods in turn are connected to each other to allow users in different pods to interact with each other. This matches the “distributed network of centralized networks” description. Is federation just a synonym for decentralization, then? It depends on who you ask.