A method of detecting bots, preferably in an operating environment supported by a content delivery network (CDN) that comprises a shared infrastructure of distributed edge servers from which CDN customer content is delivered to requesting end users (clients). The method begins as clients interact with the edge servers. As such interactions occur, transaction data is collected. The transaction data is mined against a set of “primitive” or “compound” features sets to generate a database of information. In particular, preferably the database comprises one or more data structures, wherein a given data structure associates a feature value with its relative percentage occurrence across the collected transaction data. Thereafter, and upon receipt of a new transaction request, primitive or compound feature set data derived from the new transaction request are compared against the database. Based on the comparison, an end user client associated with the new transaction request is then characterized, e.g., as being associated with a human user, or a bot.