This read-only Integer32 (0..2147483647) reports the Call Reference of the call as seen on the partner interface, letting the two sides of a call leg be matched even though each interface assigns its own call reference locally. An administrator uses this to stitch together the call table entries on the ingress and egress interfaces into a single end-to-end view of one call passing through the switch. For example, an engineer follows cwspCallOtherIntfCallRef from the ingress entry to look up the matching entry keyed by that reference in the egress interface's call table, confirming call continuity through the node.