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Cisco 10005 ESR Hardware Overview and Maintenance Guide
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Chapter 3 Maintaining the Cisco 10005 ESR
Redundancy
Service providers trying to decide on the level of redundancy appropriate for their
operations must examine their business models. The service provider invests more
heavily in high network reliability if the business model
•
Calls for protected services
•
Provides customer service-level agreements
•
Accommodates customers that require a high degree of reliability
•
Emphasizes overall reliability as opposed to cost
In addition, the service provider discusses the situation with the supplier to
identify those software and hardware features likely to experience the most stress
and thus to have the shortest mean time between failures. The point is to
determine, not just whether or not redundancy is to be used, but also the quantity
to be used (1:1, 2:1, or greater).
Some service providers have redundant chassis, but not redundant routing
engines. This approach gives them increased flexibility, so that they can provide
reliable service and accommodate a growing number of customers. Customers
requiring the highest levels of network reliability and availability often add
redundancy by connecting to two different service providers.
Situational Analysis
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