In general, an implementation must be conservative in its sending behavior, and liberal in its receiving behavior.
About this quote
- What does it mean?
- Systems should send data cautiously but handle incoming data generously to ensure compatibility.
- In plain terms
- Be strict with what you send and lenient with what you receive.
- What can you take from it?
- Design systems to be robust against unexpected inputs.
Where it applies
Putting it to work
Questions to consider
- How loose should input validation be?
- What happens when standards diverge?
Another view
Being too liberal in receiving can sometimes lead to security vulnerabilities.
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A name indicates what we seek. An address indicates where it is. A route indicates how we get there.
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