T42G, Gigabit and PoE

[Sacha]

Hello,

I have T42G phones hooked to a Zyxel Gigabit switch with PoE. However, my phone switches back to 100Mbit/s, despite having both the phone and switch set the port to auto. If I try to force the phone to gigabit, nothing changes. If I force the switch, then the switch and the phone do not connect (i.e. the phone keeps rebooting until I change the configuration back to auto or 100Mbit).

Is it possible to use T42G with Gigabit AND PoE? If so, anything to do on the T42G side or the Switch?

Thanks.

[Werner1959]

I am using a T42G with a TP-Link TL-PoE150S Power over Ethernet (PoE) Single-Port Injector. In the "Status" of T42G is shown "WAN Port Status 1000Mbps Full Duplex". So it seems to work.

[jolouis]

This is going to sound stupid, but have you checked the cable/wiring? Gigabit requires all four pairs of the Cat.5/Cat.6 cable, while 100M only uses two pairs. So most often when you find 100M works but Gigabit will not, it's because you're using a shabby patch cord or a cable that is not terminated/done properly. (Gigabit will also fail if colors are in the wrong order, etc... standards exist for a reason!)

[Sacha]

(12-16-2016 04:50 PM)jolouis Wrote:  This is going to sound stupid, but have you checked the cable/wiring? Gigabit requires all four pairs of the Cat.5/Cat.6 cable, while 100M only uses two pairs. So most often when you find 100M works but Gigabit will not, it's because you're using a shabby patch cord or a cable that is not terminated/done properly. (Gigabit will also fail if colors are in the wrong order, etc... standards exist for a reason!)

Jolouis, thanks for your note. In networking, there are never stupid ideas! You were right: one of the two ports I was using had a defect: I moved to the other port and it work at gigabit speed with PoE now, thanks!