This is the jitter counterpart to cktOspfCtd, bounding the maximum cell delay variation OSPF path selection will tolerate for this circuit, which matters far more than raw delay for isochronous traffic like voice or video where consistent timing matters as much as low latency. An admin provisioning a real-time CBR circuit would set a tight cktOspfCdv to steer routing away from paths that, while perhaps not the slowest on average, have unpredictable jitter that would degrade voice quality. For example, setting cktOspfCdv to 150 rules out any candidate path whose cell delay variation would exceed 150ms, favoring more consistent routes over merely fast ones.