Customized call lists for voip systems using high-level programming

In a system having a data communications server configured to interface with remotely-situated client entities, via wide-band networking, using a first programming language that relates to a protocol between the data communications server and data sources, the data communications server configured as a private branch exchange (PBX), the system further having a communication control circuit integrated communicatively with the data communications server and a computer-readable medium having stored thereon, instructions which may be executed by computer circuitry that includes the data communications server and the communication control circuit to perform a method comprising:

• performing data communications routing via the data communications server;
• identifying, in response to receipt of incoming data communications directed to a particular client entity, client-specific sets of control data, wherein the client-specific sets of control data are derived from instructions written in a second programming language, provided from a communication endpoint operated on behalf of the particular client entity, that is compatible with the first programming language, the first and second programming languages to facilitate limited use of the data communications server via a limited set of communications control operations and functions in each of the client-specific sets of control data;
• and
• determining, for the incoming data communications and based on the client-specific sets of control data, whether certain communications routing is to be blocked and, in response, executing a set of instructions accordingly by permitting or blocking routing of the incoming data communications by the PBX.