Showing results for 
Search instead for 
Did you mean: 

Feature Request: New Topology Option needed


The other day I could not get my system to update the time.  I called support and found that the ntp is hard coded into the system and it needed to have a WAN connection for getting to the NTP server.

I was told by support that I had to have a live IP address exposed to the Internet.  Luckily I had a block of 5 ip addresses and a spare one to use for the system.  But this is not optimal for me, nor is it real world for most of my clients.

I am using the Topology Setting for UC320W Routes Voice Only even thought I have an SBS server in place and a Sonicwall Firewall.

I would like to be able to configure the uc320w without any exposure to the internet.  So just one IP address on my LAN is all I really want or need here.  Why can't the uc320 find the Internet via my LAN and it's Gateway?

Scott Huotari

Creative Computer Solutions, Inc.

(OK, I promise this is my last feature request for today...  Really....   )

9 Replies 9


>I called support and found that the ntp is hard coded into the system  and it needed to have a WAN connection for getting to the NTP server.

>I was told by support that I had to have a live IP address exposed to the Internet.

Hi Scott,

The UC320W will work fine behind a NAT device with no public IP adddress exposed.

Some partners perfer to put a public IP address for remote managemnet. The same can be accomplished by forwarding port 8080. Another popular practice is having a LAN based device (e.g. PC) that can be controlled remotely (e.g. Teamviewer). This way you don't even have to forward port 8080. Remote access is a best practice recommendation, not a requirement for the UC320W to work properly.

It is correct that the NTP server is hard coded. That is by design so the installer does not have to bother with the setting of either NTP or system clock. We have gotten positive feedback for simplicity. But there is no need to have a "live IP addresss" exposed to the internet. I apologize for the incorrect information or misunderstanding from the support center. If a case was opened and you don't mind, please contact the support center to have the case note updated.



I just unplugged the WAN connection and rebooted the system.  The phones went to 1/1 at midnight.  After a few seconds, the phones all got a time set from NTP and were fine.  Then...  after a few minutes...

The time changed to 2:15p, then 3:08a, then ....  You get the idea.  It keeps setting the time to random times....  Then the date started changing to 3/30, then 3/31 then back to  3/30.

Thank you for working on this with me.

Scott Huotari

Creative Computer Solutions, Inc.

You unplugged the WAN connection and leave it unplugged? The system must have a WAN connection (private IP address from a NAT device is fine) reaching the internet. Otherwise it can not initialize its system clock after the reboot. There is no battery (more environmental friendly) powered RTC in the UC320W.

Also current firmware version 2.0.6 requires the WAN IP address stays constant after the system boot up. This is not a problem for large majority of the deployment even it is DHCP. In other cases, static IP is recommended.

Christopher Edgeworth
Frequent Contributor
Frequent Contributor

Hi Scott,

In the 2.0 release the UC320W acts as a router and requires a WAN connection.  We do have on the feature list for consideration for a future release the ability to connect the UC320W into the network as an application appliance as requested.

Let's see if we can figure out a topology that may help get you going in the meantime.  I'm not familiar with the capabilities of the SonicWall Firewall.  Can you configure another routed interface or VLAN on the Sonicwall to do something like the image below where the round edge router is the SonicWall?

Depending upon your customer's network requirements you may also be able to place the UC320W inline behind the SonicWall, so you would have Internet -> SonicWall -> UC320W -> Switch -> Phones/PCs.

Hope this helps.



I would like to add my support to an appliance version. We have many small networks often SBS that do not have the infrastructure to support complex VLAN routing and multiple DHCP.

Also any branch offices with a VPN could then join the voice network without complication.



I am in the process or replacing our old Asterisk PBX with a UC320W.  The way that I configued the UC320W to work behind our firewall is as follows:

1) Under Network -> Topology, I selected "UC320W Routes Voice Only"

2) Under Obtain a Data VLAN address for the Cisco UC320W from: I selected Static IP Address and entered a private IP address and Subnet mask that is not in the same range as my actual internal LAN segment.  Example:  IP Address:  Subnet Mask:  I did not enter any gateway / dns settings.  (Note: Step 4 below did not work for me if I tried to use DHCP or an IP address in my internal LAN setment's range.)

3) Under Network -> WAN, I selected Static IP for WAN Type and gave the UC320W's WAN port a private IP address on my internal LAN segment.  In my case, my internal LAN IP range is 192.168.199.X.  I also entered the revelant gateway / dns information so the UC320W can access the Internet.

4) Under Site -> System Access, I enabled remote management of the Cisco UC320W via HTTPS.  This way, I can connect to the management UI via HTTPS://192.168.199.X:8080 from my LAN segment.

5) I have the WAN port of the UC320W physically connected to my LAN segment.

I am still waiting for my phones to arrive. For now, I am testing using an old analog phone connected via the FXS port.  Using the above settings, I have successfully registerd a SIP trunk with my provider and I can make and receive external phone calls.  Our firewall currently handles SIP transformations and the UC320W is working well with this configuraiton.  I will follow up and let you know if everything works well once the phones arrive.



I agree that does work and it can route through the local LAN out to the internet and hence to a SIP provider.

The issue I have is we have a couple of branch offices on VPN on our LAN and the phones cannot then see the UC300 as they are behind an "internal" firewall. The operation of the UC300 is first class and do not feel you will have any problems with what it does.

I will be interested how the phones get on when connected with registering.


Update:  Our SPA502G phone arrived yesterday afternoon.  I setup the phone's MAC in the UC320W and connected it to LAN port 1.  The phone updated firmware and provisioned fine.  I was able to send and receive calls via both the FXO port as well as through my SIP trunk provider.

Just to play (and I know this is not "good practice"), I decided to see what would happen if I connected the WAN port of the UC320W to one of the LAN ports on the UC320W; the unit is configued to route voice only.  I then connected a switch to a second LAN port on the UC320W; I moved the SPA502G phone to the external switch.  Everything worked, and I did not see any indication of a loop issue.

With that said, sometimes when I reboot the UC320W with it's WAN port connected to it's LAN port, it does create a loop situaiton as it is booting up.  This shows itself via the WAN and LAN port LED activity being pegged constantly.  Also, when this happens, the SPA502G constantly reboots and will never register.  Other times, the UC320W will reboot fully and the loop issue never happens.  When it boots up without a loop issue, everything works fine.  Again, I know this is not "good practice" and should not be used in a production environment.  I was just curious if it would work in the first place.

All this to say that it would be quite handy to be able to disable the WAN port and have full functionality of the UC320W via the LAN connection.  My office is small and I can easily have just IP phones connected to the LAN side of the UC320W.  I know of other environments where this would not be an option.



Thanks for your feedback on the adding functionality for LAN only deployments.   Your feedback has been captured and added to product enhancement list for the UC320W.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers