End-to-End Arguments in System Design
What is the Problem?
- Placing functions at lower levels of a system may not be beneficial
- Functions generally know best, and error checking can therefore be redundant
- Low level function placement may be costly
- A correct comms system can only be built with endpoints
- Ex: detecting crashes, delivering/sequencing messages, etc.
Summary
Low Level Functionality
- Paper argues that low-level functionality is mainly a performance optimization
- If the probability of an error is low, doesn't make sense to add error checking in the middle of the system. Instead, let the endpoints handle it
Weakness
- Maintainability (checks missing in the middle)
- Certain systems ought to have intermediate checks (e.g. comms over lossy media)
- Catching errors can take longer, needs to make it all the way to an endpoint to detect