I Can Register But Can Not Establish A Call; I Can Make A Call But The Voice Only Goes One Way Not In Both Ways; I Can Receive A Call But The Voice Only Goes One Way Not Bothway; If All The About Have Been Tried, But Register Still Fail What Should I Do - ZyXEL Communications P-2302RL-P1 Support Notes

P2302RL-P1 Support Notes
1. Make sure the Internet is reachable and the SIP register server is reachable. If your register server uses
domain name make sure DNS name can be resolved. If you are using static WAN IP make sure DNS server is
configured correctly on your ZyXEL Device.
2. Make sure the SIP account is correct and the password is key in correctly.
3. Check if there is NAT router before it. Prestige is a VoIP station gateway. We do not suggest to have an
NAT router before it as it may cause many unexpected problem. If you have an NAT router before it we
suggest to use a VoIP ATA (VoIP Analog Telephone Adapter) such as Prestige ATA series.

I can register but can not establish a call?

If you can register to server but can not make a call very likely there is NAT router or firewall before it which is
blocking it. We do not suggest to have an NAT router before it as it may cause many unexpected problem.
If you have an NAT router before it we suggest to use a VoIP ATA (VoIP Analog Telephone Adapter) such as
Prestige ATA series.
If the problem is a firewall before it. Please check with the firewall manager, make sure the SIP protocol is
allow to pass-through firewall, and the range of RTP port is allowed through firewall.

I can make a call but the voice only goes one way not in both ways?

If you can register to server and I can make a call signal establishment but the voice only goes one way. In this
case it is very likely there are NAT router or firewall before it, please see NAT/firewall related question above.

I can receive a call but the voice only goes one way not bothway?

If you can register to server but can only make out going call but can not receive incoming calls or the incoming
call signal establishment can be made but voice only goes one way very likely there is NAT/firewall router
before it, please see NAT/firewall related question above for tips to troubleshoot.

If all the about have been tried, but register still fail what should I do?

In such case, please contact your local vendor for support. If they can't help out the problem they will escalate
your problem to ZyXEL tech center. To report a problem please prepared below info.
1. Serial number of the device.
2. SIP Call server type and vendor.
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