Abstract: According to various embodiments, techniques and mechanisms described herein facilitate the identification of fraudulent request messages. In one example, a request message associated with a user identifier is received at a request server in a request system that includes a plurality of such request servers. An estimated message count value associated with the user identifier is identified. The estimated message count value identifies an estimated number of messages associated with the user identifier that were previously received by the request servers. A response message is transmitted when it is determined that the estimated message count is below a designated threshold.