Ann, a user, reports that her desktop phone is not working on one cable.
However, that cable provides connectivity to her laptop.
A technician determines PoE is not provided to the end device.
Which of the following is MOST likely the cause?
A.
Transceiver mismatch B.
Crosstalk C.
Jitter D.
Open/short on the cable.
A.
Ann, a user, reports that her desktop phone is not working on one cable.
However, that cable provides connectivity to her laptop.
A technician determines PoE is not provided to the end device.
Which of the following is MOST likely the cause?
A.
Transceiver mismatch
B.
Crosstalk
C.
Jitter
D.
Open/short on the cable.
A.
The most likely cause of the phone not working but the laptop is working is the lack of Power over Ethernet (PoE) provided to the phone. PoE is a technology that allows power to be sent over the same Ethernet cable used for data transmission, eliminating the need for a separate power source for devices such as IP phones, wireless access points, and IP cameras.
The phone may be designed to receive power from the Ethernet cable, but if PoE is not provided to the device, it will not power on. The laptop, on the other hand, does not require PoE to function, so it can still connect to the network and access the Internet even if PoE is not present.
The other options listed, such as transceiver mismatch, crosstalk, and jitter, are less likely causes of the problem. Transceiver mismatch occurs when the transceivers at each end of the Ethernet cable are not compatible, but this is unlikely to be the case if the laptop is working on the same cable. Crosstalk is interference caused by signals from adjacent wires in the cable, but this would affect both the phone and the laptop, not just the phone. Jitter is the variation in the timing of digital signals, which can cause errors in data transmission, but this is unlikely to cause the phone to not receive power.
The open/short on the cable could be a possible cause, but it would affect both the phone and the laptop, not just the phone. Additionally, an open/short would likely result in the cable not working at all, rather than just affecting the phone's ability to receive PoE.
Therefore, based on the information given, the most likely cause of the phone not working on the cable that provides connectivity to the laptop is the lack of PoE provided to the end device.