In the attached file I got confused to what I have found : is two different figures from two different sites
http://img214.imageshack.us/img214/4282/fxoandfxsciscoandpbxlw5.jpgFrom the top in the first figure FXS for SmartNode 2300 ( I guess it is a voice gateway ) is connected to FXO for PBX.
While in second Figure FXO for Cisco router (it is a voice gateway ) is connected to FXS for PBX.
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