VoIP (Voice Over Internet Protocol) Qualification - CableIQ

Cabling that qualifies for VoIP will support the voice over IP application; however, the quality of service may vary depending on other factors. These factors include the quality of the transmission system between the far-end VoIP device and your cabling, the equipment used, and the equipments QoS (quality of service) settings and performance.
The test is essentially the same as 100BASE-TX plus dc loop resistance.