Perplexity published a practical guide to LLM gateways on October 27, 2026, walking engineering teams through how the intermediary layer routes, authenticates, caches, and logs model calls and cataloging the security and reliability risks of concentrating provider credentials in one service. Gateway Definition and Taxonomy The guide defines an LLM gateway as a reverse proxy for model calls: applications send requests to the gateway instead of directly to providers such as OpenAI, Anthropic, or…