This read-only Integer32 (0..2147483647) reports the Maximum Cell Delay Variation negotiated in the backward direction for this call on this interface. An administrator uses this as the jitter ceiling for the call's return path, useful when the backward direction independently carries jitter-sensitive traffic. For example, an operator diagnosing choppy audio on the return leg of a call checks measured backward jitter against cwspCallMaxBwdCdv to see if the negotiated bound has been breached.