Decentralized architecture offers a robust and flexible structure for online platforms, since centralized moderation and computation can be easy to disrupt with targeted attacks. However, a platform offering a decentralized architecture does not guarantee that users will use it in a decentralized way, and measuring the centralization of socio-technical networks is not an easy task. In this paper we introduce a method of characterizing community influence in terms of how many edges between communities would be disrupted by a community's removal. Our approach provides a careful definition of "centralization" appropriate in bipartite user-community socio-technical networks, and demonstrates the inadequacy of more trivial methods for interrogating centralization such as examining the distribution of community sizes. We use this method to compare the structure of multiple socio-technical platforms -- Mastodon, git code hosting servers, BitChute, Usenet, and Voat -- and find a range of structures, from interconnected but decentralized git servers to an effectively centralized use of Mastodon servers, as well as multiscale hybrid network structures of disconnected Voat subverses. As the ecosystem of socio-technical platforms diversifies, it becomes critical to not solely focus on the underlying technologies but also consider the structure of how users interact through the technical infrastructure.

翻译：去中心化架构为在线平台提供了稳健且灵活的结构，因为集中式的审核与计算容易受到针对性攻击的干扰。然而，提供去中心化架构的平台并不能保证用户会以去中心化的方式使用它，而测量社会技术网络的中心化程度并非易事。本文提出了一种方法，通过评估移除某个社区会破坏的社区间连边数量来表征社区影响力。该方法为"中心化"提供了适用于用户-社区二分社会技术网络中的审慎定义，并论证了诸如考察社区规模分布等更简单方法的不足。我们利用该方法比较了多个社会技术平台的结构——包括Mastodon、代码托管服务器、BitChute、Usenet和Voat——发现了从互连但去中心化的代码服务器到实际呈现中心化使用的Mastodon服务器，以及由相互隔离的Voat子版块构成的多尺度混合网络结构等一系列结构形态。随着社会技术平台生态系统的多元化，不仅要关注底层技术，更需审视用户如何通过技术基础设施进行交互的结构形态，这已变得至关重要。