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CoA · RFC 5176

Engineering · 2026-05-20 · 11 min read

CoA-Disconnect under one second: the design we shipped

Operators told us their old billing system took 2-3 minutes to suspend a non-paying customer. We rebuilt the path end-to-end. Here is the architecture, the retries, and the trade-offs we made to land at sub-second.

Wanjiku K.

Staff engineer

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Field notes from operators & engineers.

CoA-Disconnect under one second: the design we shipped

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