Certain aspects of the disclosure are directed to routing decisions implemented in response to data communications. According to a specific example, one or more computer processor circuits are to interface with remotely-situated client entities using a first programming language, and to provide a database of data communications services based on a subscription. In response to receipt of a data communication, client-specific sets of control data can be identified. The client-specific sets of control data are derived from programming instructions received over a message exchange protocol and corresponding to a second programming language that is compatible with the first programming language. Based on the client-specific sets of control data and using a numbering plan area (NPA) code of the received data communication, a nearby extension of the client entity can be identified, and the received data communication can be routed to the nearby extension.