11
Distributed Systems
Postel's Law
Fault Tolerance — the Robustness Principle.
The article
If
In a distributed system, assuming everyone follows the spec perfectly leads to brittle failures.
Then
“Be conservative in what you send (strict compliance) and liberal in what you accept (handle messy inputs gracefully).”
Unless
Fail-Fast (Internal only)
Source
Jon Postel, RFC 761 (DoD Standard TCP, January 1980) §2.10 — "be conservative in what you do, be liberal in what you accept from others". The same guidance appears in RFC 760 (IP) §3.2 in different words, and verbatim again in RFC 793 (1981).
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