SIP uses the high availability features that are included in the product to offer a comprehensive high availability solution.
A core group is a set of processes that handles high availability activities. Each core group has a coordinator function that manages all the singleton services running in the core group. Typical SIP deployments require only a single core group. For extremely large-scale deployments, such as 50 or more cell members, multiple core groups may be required.
For more information on core groups, see Core groups (high availability domains)
The Core group failure detection mechanisms and algorithms are documented in Core group discovery and failure detection protocols