Extracted from: http://blogs.technet.com/b/wbaer/archive/2015/09/18/distributed-cache-in-sharepoint-server-2016-it-preview.aspx
The Distributed Cache service provides in-memory caching services to several features in SharePoint Server 2016 IT Preview.
Some of the features that use the Distributed Cache service include:
- OneNote client access
- Security Trimming
- Page load performance
These features use the Distributed Cache for quick data retrieval. The Distributed Cache service stores data in memory and does not have a dependency on databases in SharePoint Server 2016 IT Preview. However, some SharePoint features may store data in both the Distributed Cache and databases.
Distributed Cache Improvements in SharePoint Server 2016 IT Preview
SharePoint Server 2016 IT Preview improves Distributed Cache performance and resiliency through a change which switches off NTLM authentication between SharePoint and the cache cluster; instead relying on encryption of cache data before transport. In SharePoint Server 2013 under load/high scale – the cluster would start getting unresponsive to calls from SharePoint due to authentication overhead. i.e. every call from SharePoint, the cluster had to authenticate the call with AD. This change also allows SharePoint Server 2016 IT Preview Distributed Cache clusters to scale up the number of client connections to help with throughput.
Topologies with MinRole and Distributed Cache
The Distributed Cache component is on by default in the SingleServerFarm role and in the Cache role for SharePoint Server 2016 IT Preview.
To learn more about MinRole roles and services see also https://technet.microsoft.com/en-us/library/mt346114(v=office.16).aspx.
Single Server Farm Example
All services isolated to the scope of single machine to include Distributed Cache.
Content + Search Farm Example
All services isolated with the scope of a server farm. Distributed Cache hosted on one or more dedicated servers.
Content Farm + Search Farm Example
Services distributed across one or more content farms and one dedicated search farm. Distributed cache hosted on one or more dedicated servers with the scope of the content farm.
Content + Service Farm Example
Services distributed across one or more content farms and one dedicated service farms. Distributed cache hosted on one or more dedicated servers with the scope of the content and/or service farm.