This read-write integer sets the maximum depth of a channel's ingress queue, in cells, beyond which incoming cells begin to be dropped, with the AUSM 4-port card constrained to a narrower 1-8000 range than the general 1-16000 syntax. Admins tune this to balance buffering (which absorbs bursts but adds latency) against cell loss under sustained overload, and it also anchors the related CLP threshold settings below it. For example, an admin might increase ingrQDepth for a bursty VBR data channel to reduce cell loss during traffic spikes, accepting some added latency in exchange.