ITU G.703 specification give Industry standards for OEM’s like Alcatel, but it’s no problem in do a convertion. Only impedance adaptation: BNC = 75ohms ; RJ45 = 120ohms.
This means you have a Tx (Out) and Rx (In) on a single RJ45 jack. and you could connect it where do you need.
Take attention to signalitation problems.
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