VoIP Cloud is a product that serves as an intermediate layer between LXCRM and VOIP service providers designed with the following requirements in mind:
VoIP Cloud presents the event model that covers various VoIP usage scenarios including:
The cloud supports both outgoing and incoming events explained in Contracts section. Voip Cloud may supply additional Metadata with any event it emits.
General design of the VoIP Cloud solution:

The VoIPCloud itself is implemented as stateless web service and provides HTTP(S) REST endpoint to receive incomming events.
Also it is capable of dispatching StartCall event triggered by the CRM user to the subscribed VoIP services endpoints. (Subscription is managed by Leverate Support/Integration teams according to availability.)
The definition of contracts, request sighning and general direction on how to integrate with the service can be found here