Unmanaged large buffers in today's networks have given rise to a slew of performance issues.  These performance issues can be addressed by some form of Active Queue Management (AQM) mechanism, optionally in combination with a packet scheduling scheme such as fair queuing. The IETF Active Queue Management and Packet Scheduling working group was formed to standardize AQM schemes that are robust, easily implementable, and successfully deployable in today's networks.  This document describes various criteria for performing precautionary characterizations of AQM proposals.  This document also helps in ascertaining whether any given AQM proposal should be taken up for standardization by the AQM WG.