A hybrid network (100) includes a plurality of network elements (102, 106, 110, 114) that are coupled together by communication links (116, 118, 120, 122, 124). The network elements operate on different communications protocols. A loop back test message traverses a path (140) across network elements to test the integrity and quality of the path. Each network element that receives the loop back message modifies the message in a predetermined manner. The originator of the message verifies that the message was modified in an appropriate manner and in an appropriate time frame to determine integrity and quality.