Intrusion Detection Systems (IDS) based on autonomous agents are important security tools to protect distributed networks and they can be considered critical systems. For this reason; we have proposed a security scheme to verify the entities? integrity inside the IDS architecture named Cooperative Itinerant Agent (CIA). The proposal includes software watermarking and fingerprinting techniques. Moreover, in this paper we infer a formula to calculate the time consumed by a CIA to perform entities? verification in a determined level of the infrastructure in order to evaluate the agent?s scalability. The parameters of this formula are the network?s throughput and delay.