Designing an Internet

Clark served as the IETF's chief protocol architect for fifteen years and helped shape the design principles that became the internet's foundation.

This book is his retrospective: not a memoir but a systematic analysis of which architectural decisions were inevitable given the constraints and which could have gone differently.

He distinguishes between designing "the Internet" — the specific artifact we have — and designing "an internet" — the broader class of possible large-scale networks.

The framework forces the reader to separate contingent choices from structural necessities, a discipline directly transferable to product architecture.

Clark is unusually honest about the tradeoffs embedded in end-to-end design, layering, and the tussle between stakeholders with incompatible goals.

Available as free open access from MIT Press, making it one of the most valuable no-cost readings on network design available.