Characterizing Network Centralization and Observability in the Remote MCP Ecosystemnew
A measurement study of 179 remote MCP servers finds heavy infrastructure concentration (HHI 0.736) and a security-observability tradeoff in platform OAuth.
The paper introduces a three-tier observability framework (catalog metadata, passive compliance signals, live vulnerability analysis) applied to a stratified sample of 179 remote Model Context Protocol (MCP) endpoints from two public registries. The Herfindahl-Hirschman Index over ASN distribution is 0.736, well above the 0.25 high-concentration threshold, and 95% of commercial PaaS-hosted servers enforce gateway-level OAuth 2.1 with PKCE. Authentication correlates strongly with hosting platform choice rather than operator configuration, creating a security-observability tradeoff that constrains automated scanning for tool-poisoning vectors without prior credentials.