Respond, restore, resolve: Achieving 7-nines availability telecommunications systems in the field
Charles Eugene McPhail · Bell Labs Technical Journal · 2006
Achieving telecommunications systems with 7-nines (0.9999999) availability requires taking a 5-nines telecommunications system and providing extremely responsive and technically excellent customer support. 5-nines telecommunications systems have robust hardware and software reliability assets and are designed to meet demanding serviceability and maintainability requirements. These assets are characterized by extremely low failure rates, fast recovery times, and a high automatic recovery coverage rate. However, to surpass 5-nines availability, excellent human observation and intervention are required. The theme “respond, restore, resolve” is the jingle of an important customer support reliability pattern. It is meant to help remind field support engineers of the best-in-class overall strategy for responding to customer issues. This and other important customer support patterns that impact reliability will be described in detail. The audience for the paper includes members of customer technical support organizations as well as telecommunication system architects and designers who hope to build systems capable of achieving very high availability.