In computer networking, the '''Application Session Controller''' (ASC)''' [[network element]] resides at the [[application layer]] and sits between the application layer and the [[core network]] to provide and manage connectivity to the evolving [[Telecommunication|telecom]] [[Telecommunications network|network]]. The ASC incorporates a number of open standard APIs, plus the signaling, media between disparate networks that converged.<ref>{{cite web |title = Application Session Controller |work= Definithing web portal |url= http://definithing.com/define-tech/application-session-controller/ |accessdate=1 June 2016 }}</ref> It insulates the application [[server farm]] from the network below via a programmable network abstraction engine, thereby providing the application specific call-control functions independent of each network.
The ASC incorporates a number of open standard [[Application programming interface|APIs]], plus the signaling, media, and the feature inter-working between disparate networks that converged and consolidated applications require. It is scalable to support tens of millions of subscribers via a single system or via clustering and provides the necessary calls per second / transactions per second required for large-scale multi-network environments.
