Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

SPA3102 invite answer with IP Wan address


I have the following configuration of a SPA3102:

Line 1 registred with an ITSP and one analog phone connected to the corresponding port

Wan interface in DHCP connected to Internet

Lan interface with static IP address.

Every thing works fine when i use my phone to call someone outside.

Now i would like to call my analog phone from a softphone (eg X-Lite) located on my Lan. When i dial userid@ip-spa3102 (where ip-spa3102 = Lan interface IP address) the connection is established and the person using the phone hear me but i hear nothing from the softphone side. On the Lan trace i can see that the SPA3102 put always her IP Wan address in the invite answer packet of the SIP protocol, then i suppose that it sends all the RTP packets to this IP Wan address. I tried to change the configuration according a lot of document i could read but with the same result.

I would be very happy if somenone could tell me if it's possible to have both registred ITSP and softphone working on Line 1 and if yes, what i have to change in my configuration in order to call my analog phone from a softphone? 

Thank you


SPA3102 invite answer with IP Wan address

The audio problem occurs because of a mis-communication of ip address ... local network vs external ip address.

I believe it is possible to setup direct ip calling over the local network and also have Line 1 configured for registered calling with your voip provider.  You may need to experiment with different settings.  I successfully tested a calls from my XLite to my SPA3102 with several different settings.  Different routers may operate differently.

First, for a quick fix, with Line 1 configured with NAT Mapping Enable: Yes, a call to Line 1 will respond showing the SPA3102's external ip address.  If you change the setting to NAT Mapping Enable: NO then that may fix the communication problem with XLite but you may have a problem with the registration or calls with your voip service provider calls.  Try it and see if (1) That fixes the local network direct ip call from XLite and (2) If that setting causes no problems with your registered voip account on Line 1.

Assuming the above quick fix causes problems with your registered voip provider calling, go back to the NAT Mapping Enable: Yes setting and try setting up XLite to call your SPA3102's external ip address.  You can either try calling your numeric external ip address or you can get a symbolic ip address from a service like DynDNS.  I tested it with a symbolic ip address.  You will need to port forward your SPA3102 Line 1 Sip Port in your router to your SPA3102 and possibly need to forward the SPA3102 RTP Port Range to the SPA3102.  You can find the RTP Port Range on the SPA3102 Sip Tab.

My XLite also has several NAT settings that you can also vary on the Account Settings -->Topology Tab.

Auto-detect firewall traversal using ICE



Local IP address

New Member

SPA3102 invite answer with IP Wan address

Thanks for this quick answer.

I have already Line 1 Nat setting to yes.

Something i have omitted to mention is that the SPA3102 is directly connected to the ITSP ethernet jack dedicated for the VOIP i have no router between this WAN and my LAN.

Then the SPA3102 would not be able to do something like a routing between the two networks and it means that i have to add a router ?

SPA3102 invite answer with IP Wan address

My experience is that sip calls do not work well (or at all) thru the SPA3102 ethernet jack.  The SPA3102 router is for users to be able to attach a computer to the internet.  Sip calls need to go thru the internet jack of the SPA3102.

New Member

SPA3102 invite answer with IP Wan address

It's OK now i've implemented a router between the two network and it works fine! Strange behavior.

Thanks again.

CreatePlease login to create content