The method involves transmitting plural endpoint probes to produce plural endpoint probe results indicating the preparedness of the endpoints for calls routed thereto; identifying similarly situated endpoints; and representing each of the similarly situated endpoints by a reduced number of recorded endpoint probe results that substantially represent the inter-connective preparedness of each of the similarly situated endpoints. The apparatus includes a mapping mechanism for mapping the probe results for the similarly situated endpoints into a reduced number of endpoint probe results that substantially represent the inter-connective preparedness of each of the similarly situated endpoints, and a recording mechanism for recording the reduced number of endpoint probe results. Such mapping permits an Internet operating system (IOS) router/gateway to act as an real-time responder/service assurance agent (RTR/SAA) proxy on behalf of non-RTR/SAA capable voice over Internet protocol (VoIP) endpoints.