[campuschill]

Hi,
I have been posting about audio problems on my stanaphone line for almost 3 months now without any solution yet. The line is registered on my SIPURA 3000 Line 1, with PSTN line currently disabled.

I was running 3.1.10d firmware and when "STUN test Enable" was set to yes, the syslog file showed "Warning 399: Symmetric NAT Detected", even if i put the ATA in DMZ.

However when i downgraded my firmware to 2.0.13g the syslog file shows "Warning 399: Full Cone NAT Detected".

I ran WinStun test for server stun.fwdnet.net:3478 and i get the following results
Nat with Independend Mapping and Port Dependent Filter - VoIP will work with STUN
Preserves port number
Does not supports hairpin of media
Public IP address: xx.xx.xx.xx

When i do what is my IP from Voxilla home page from my wired network desktop then the ip matches the ip on my routers WAN port. However if i run the same from my laptop which is wirelessly connected to the same router i get a IP different from my WAN IP.

I have tried with and without STUN enabled, with and without port forwarding, with and without DMZ. I also tried putting sip.stanaphone.com as outbound proxy. Except for a few stanaphone numbers most of the calls i make (both stanaphone and PSTN) cannot hear me after a few minutes in the call, while I can still hear them.

I am on COMCAST cable 6 Mbps/384 Kbps line with Motorola SB5120 Modem. Is there a chance that the firewall outside my home network is symmetric....Please...please...help...

[maplekent]

Make sure you are not using compact headers, in the
942 it triggers a NAT bug (likely does in the
2000/3000 too).

What do you mean by firewall outside your home network?

The fact that it works for a few minutes and then
fails says "BUG" to me. The bug could be in your NAT
box or the destination NAT box. One of them could be
blowing away a translation when it really shouldn't.

You mention that you get different IP addresses
"from Voxilla home page" for your desktop versus
your laptop. Does one of them use a web cache
and/or web proxy? Try these:

http://www.myipaddress.com/
http://www.ipchicken.com/

The second one gives you info about the web browser
it thinks you are using. If the info doesn't match
your set-up, then you are likely hitting a web cache.

-mark

[campuschill]

Hi Mark,
Thanks for your reply. Compact header is disabled in my current configuration. When I typed "firewall outside home network", i meant at the ISP end.

I tried

http://www.myipaddress.com/
http://www.ipchicken.com/

Both of them give the same IP address both on my desktop and laptop, which matches the external IP shown on the Sipura Info page. Also ipchicken browser detection matches what i use.

However http://voxilla.com/whatsmyip.php reports different ip on my laptop and desktop. The ip reported on the laptop does not match the external IP on the Sipura Info page, while that reported in the desktop matches.

[campuschill]

Mark,
You were right about the wrong ip address showing up on my laptop with http://voxilla.com/whatsmyip.php

After i cleared my browser's cache, it came up with my correct public ip

[maplekent]

Originally Posted by campuschill

After i cleared my browser's cache, it came up with my correct public ip

So... does that mean that your laptop was not getting to the
page and was constantly showing you a cached page?

And what's the net effect of this on your NAT problem?

-mark

[campuschill]

Yes, I guess the laptop was showing a cached page.

I still have my NAT problem on my SPA 3000 and still losing audio in the middle of a call. Are there any more tests I can do on my network other than WinStun which will help us understand the situation better.

Thanks for your responses Mark

[maplekent]

So for the NAT settings you've got everything turned on,like this:

TAB Feature State
--------------------------------------
SIP symmetric RTP YES
SIP Handle VIA received YES
SIP Handle VIA rport YES
SIP Insert VIA received YES *
SIP Insert VIA rport YES *
SIP Substitute VIA addr YES
SIP Send Resp to SrcPort YES
SIP STUN enable YES,
SIP STUN Test Enable YES
SIP NAT keep-alive 30 seconds

EXT NAT Mapping enable YES
EXT NAT KeepAlive enable YES
EXT NAT KeepAlive Msg: $NOTIFY
EXT NAT KeepAlive Dest: $PROXY

-mark

[campuschill]

Hi,
I connected my SPA3K directly to the cable modem, still had the same problem with STUN enabled. Hence i went to back to my original setup with the router and contacted Comcast today. They gave me two IP addresses, one they said was the IP address of my modem and other was the IP of my WAN port in the router.

The WAN IP address given by comcast matched that of the IP seen through the VOXILLA what's my ip page.

I thought if i could insert the cable modem IP as the "EXT IP" value under "NAT SUPPORT PARAMETRS" it would help. However when i submit the changes SPA3K till shows my WAN IP as the external ip in its info page. Anyway I will test this setup and report back.

[campuschill]

Mark,
Looks like we typed our last posts at the same time. Anyway to your question, these are my settings

TAB Feature State
--------------------------------------
SIP symmetric RTP YES
SIP Handle VIA received YES
SIP Handle VIA rport YES
SIP Insert VIA received YES *
SIP Insert VIA rport YES *
SIP Substitute VIA addr NO
SIP Send Resp to SrcPort NO
SIP STUN enable YES,
SIP STUN Test Enable YES
SIP NAT keep-alive 15 seconds

EXT NAT Mapping enable YES
EXT NAT KeepAlive enable YES
EXT NAT KeepAlive Msg: $NOTIFY
EXT NAT KeepAlive Dest: $PROXY

[maplekent]

Originally Posted by campuschill

Hi,
I thought if i could insert the cable modem IP as the "EXT IP" value under "NAT SUPPORT PARAMETRS" it would help. However when i submit the changes SPA3K till shows my WAN IP as the external ip in its info page. Anyway I will test this setup and report back.

But... the cable modem box should be transparent to you, it should
act as a bridge. If you traceroute in to your router WAN address
(see traceroute.org) then do you see the IP address of the cablemodem?

I would hope not... I just looked up the Motorola SB5120 and it really
seems like it's not a layer 3 device. I'm pretty sure that it's just a bridge between the cable network and your network. If it has an IP address, then it's just a management address visible only to the cable operator.

Don't put in an EXT IP anyway, just turn all other stuff on and see what happens.

-mark