This is the operator-assigned name of the decap tunnel group referenced in the notification, giving a readable label for the receive-side tunnel group instead of just its numeric index. Since decap groups are typically named to match the service they terminate, seeing 'CUST-A-DECAP' in an alert tells the NOC exactly which customer's inbound traffic path is involved. This mirrors the encap-name field's purpose but specifically for the unwrapping/receive direction of the service.