ESR series service routers.ESR-Series. User manual
Configure subscribers on PBX server:
esr(config-pbx)# user 5200
esr(config-pbx-user)# profile fxs_ports
esr(config-pbx-user)# exit
esr(config-pbx)# user 5201
esr(config-pbx-user)# profile fxs_ports
esr(config-pbx-user)# exit
esr(config-pbx)# user 5202
esr(config-pbx-user)# profile fxs_ports
esr(config-pbx-user)# exit
esr(config-pbx)# user 333
esr(config-pbx-user)# profile fxo_ports
esr(config-pbx-user)# exit
esr(config-pbx)# 
Enable PBX server:
esr(config-pbx)# enable 
esr(config-pbx)# exit 
esr(config)#
Configure FXS ports. Specify number and SIP profile:
esr(config)# interface voice-port 1
esr(config-voice-port-fxs)# sip user phone 5200
esr(config-voice-port-fxs)# profile pbx fxs_ports
esr(config-voice-port-fxs)# exit
esr(config)# interface voice-port 2
esr(config-voice-port-fxs)# sip user phone 5201
esr(config-voice-port-fxs)# profile pbx fxs_ports
esr(config-voice-port-fxs)# exit
esr(config)# interface voice-port 3
esr(config-voice-port-fxs)# sip user phone 5202
esr(config-voice-port-fxs)# profile pbx fxs_ports
esr(config-voice-port-fxs)# exit
esr(config)#
Configure FXO port. Specify number and SIP profile, disable caller-id, enable 'Hostline PSTN to IP' service. Then 
specify number of subscriber that will receive calls from PSTN:
esr(config)# interface voice-port 4
esr(config-voice-port-fxo)# sip user phone 333
esr(config-voice-port-fxo)# profile pbx fxo_ports
esr(config-voice-port-fxo)# caller-id mode off
esr(config-voice-port-fxo)# hotline ipt
esr(config-voice-port-fxo)# hotline number ipt 5200
esr(config-voice-port-fxo)# exit
esr(config)#