HardwareErrors is a read-only Counter32 counting the number of hardware errors recorded for this IP-to-IP conversation. A rising hardware-error count on a specific IP-to-IP conversation points an admin toward a physical-layer problem, such as a failing NIC or bad cabling, rather than a software or configuration issue, and — since this ipsb table duplicates the row layout of the MIB's iplb table but is sampled and indexed independently — a given pair can show different collection intervals in ipsb than it does in iplb. If the pair 10.4.12.30/198.51.100.7 shows hardware errors climbing while other IP-to-IP conversations on the same segment stay clean, that isolates the fault to the equipment involved in this particular conversation.