Overview of Key Architectural Differences

Server Configuration and Deployment

ScaleOut StateServer takes a decentralized, peer-to-peer approach to cluster management. Differences between configuration and management of ScaleOut StateServer (SOSS) and Windows Server AppFabric Caching are highlighted in the following sections.

Configuration Storage

Windows Server AppFabric Caching
WSAF Caching requires storage of cluster configuration information in a single, centralized location, such as a SQL Server database or an XML file that is available to all cache hosts from a shared network folder.
ScaleOut StateServer
ScaleOut StateServer does not require centralized storage for cluster configuration. ScaleOut hosts automatically discover each other on a network subnet. When global, cluster-wide configuration changes are applied to a host, those changes are shared with the all of the hosts in the cluster and stored locally on each host.
[Tip] Tip

ScaleOut StateServer’s automatic host discovery feature uses IP multicast to allow hosts to find each other on a network. If multicast is disabled or not allowed on the network, a manually configured roster of potential hosts in the group can be set up and is automatically shared between ScaleOut hosts. More information about manual group management is available in the Group Management topic of the ScaleOut StateServer Help online guide.

Lead Hosts

Windows Server AppFabric Caching
WSAF Caching clusters may be configured to store cluster-wide settings in an XML file on a shared network folder. In this configuration, the cluster management role must be performed by one or more special cache hosts that are called "lead hosts". If a majority of lead hosts are offline then the entire cluster shuts itself down.
ScaleOut StateServer
ScaleOut StateServer does not use the concept of "lead hosts" to perform cluster management duties. A ScaleOut data grid is fully peer-to-peer, and all hosts in the grid share and coordinate cluster management. Hosts can (and should) be configured and deployed in an identical manner. This approach to shared responsibility allows you to take any host offline without affecting cluster management.

Platform Requirements

Windows Server AppFabric Caching
Cache hosts in Windows Server AppFabric Caching must run on the Windows platform.
ScaleOut StateServer
ScaleOut StateServer hosts can be deployed as Windows or Linux servers. ScaleOut’s communication protocols are platform agnostic; .NET client applications running on Windows can seamlessly connect to ScaleOut daemons running on Linux systems.