The solution consisted of a large production farm and a medium pre-production farm within each data centre. Making use of SQL Always On technologies allowed us to synchronise data between the data centres, supporting a hot standby scenario.
A custom claims provider was developed to eliminate network latency when resolving entities in remote user domains.
The design of each farm allowed for a set of front end servers, a set of batch processing servers and dedicated search servers to support the large, global, multi-lingual user base, whilst providing resilience within each data centre. The platform needed to provide the SharePoint cloud app model as well as all standard and enterprise edition service applications, including SQL Reporting Services and Workflow Manager.