This 4-byte octet string captures the DXI2 header of the last SMDS PDU that triggered the 'Dxi2 Link Id Invalid' violation, meaning the Link ID field inside the DXI level-2 header didn't match a link ID the switch recognizes for this port. An admin decoding these 4 bytes can identify which specific link identifier a misconfigured DXI-attached device is using, helping to spot a mismatch between the CPE's configured link ID and what the switch expects. For example, a customer's DXI-attached router configured with a stale link ID from a prior provisioning would generate this violation until its configuration is corrected to match the switch.