Various exemplary embodiments relate to a method and related network node including one or more of the following: receiving a Diameter message at the DRA from an origin device; establishing a message context object in response to receiving the Diameter message, wherein the message context object includes a first collection of child objects; evaluating at least one rule, including: modifying, based on a first instruction, a first index value associated with the first collection of child objects, accessing, based on a second instruction and from the first collection of child objects, a child object corresponding to the first index value; and transmitting a message based on the evaluation of the at least one rule.