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SPA122 FW 1.2.1 NAT-Bridge switching via IVR


obviously the switching between bridge and NAT mode, using the IVR code 201# still isn't working in the latest firmware.

201 lets you chose between NAT (0) and bridge (1) for the yellow ethernet port - at least on the SPA-2102 and SPA-3102.

The SPA122 accepts the code (at least the friendly voice prompt lady says so) the device is then rebooting, but the setting itself remains unchanged.

Am I doing something wrong or can anyone recreate the behaviour?

Computers are like dachshounds - never do what they ought to ;-)


Everyone's tags (5)

Sorry for the delay of 3

Sorry for the delay of 3 years, I just installed an SPA122 and found the codes are reversed.

Bridge is 0 and Nat is 1.

My setup is: Internet-ATA-Wireless Router.

The problem I found is that in Bridge mode, you cannot access the configuration menu ( in my setup to change the setup and was resetting the ATA 73738# to access it, loading my setup (.cfg) file again making changes and re-saving the setup file before switching back to Bridge mode.

Using the IVR 201#1#1 code the configuration can be changed (and saved) and then switched back to Bridge mode either in the configuration or by using IVR 201#0#1.

Bridge mode allows a much faster internet access than using Nat mode.

Hope this helps you and anyone else out there.


What's the target network

What's the target network topology utilizing SPA122 in bridge mode ?

For networks with switch (necessary where more than one end device wired) I consider counterproductive to pass traffic thru SPA122 ...


So it's for simplest network with no switch and just one end device wired ?


Hi Dan,Please find attached a

Hi Dan,

Please find attached a PDF showing my setup.

The reason for using Bridge mode is that NAT mode slows down the internet considerably.

Download and upload are about 7-10 Mbts in NAT whereas using Bridge, the download is 50 Mbts and upload is 20 Mbts. That's rated speed for my NBN (National Broadband Network in Australia) fibre. The use of Wi-Fi internally doesn't slow it down.

Hope the info is OK for you and you can see the reason I set it up this way. It was the simplest way for me to change over to the fibre network without having to run extra telephone wiring and the Ethernet cable had already been run beforehand.

Also, does anybody know where the undocumented IVR codes can be found? They must be somewhere.




I wish it's better (in the

I wish it's better (in the terms of stability and reliability) to use a small switch (even cheap) in place of SPA122, then connect SPA122 to such switch as another end device. E.g. overall traffic will not pass-thru SPA122 and SPA122 will neither bridge nor route - it will be just ATA (in such case SPA112 can be used instead). But well, the small switch is not for free and will draw current. As long as you will be satisfied with SPA122 bridge, it's acceptable topology.

Note I'm very surprised you have computer room with no network wiring.

If it is just missing on your schema then you should consider to avoid SPA1x2 at all. Use native VoIP phone. Not only because the superfluous conversion VoIP <->POTS will be avoided thus some features impossible with ATA setup become avaiable. Also, Cisco ATAs are known not to provide Caller-ID to connected analog phone reliably sometime. Thus it may work for you, may work just for a while or just sometime, or may not work at all with little or no change to solve the issue.


does anybody know where the undocumented IVR codes can be found? They must be somewhere.

Definitely. They can be found in the firmware sources. As we have no access to them, you need to disassemble compiled firmware. Also, common social engineering techniques can be used - if you are attractive blonde you can offer a beer (and then more) to programmer in charge to disclose some secrets to you.




Sorry for the delay in

Sorry for the delay in getting back..

I am a techie (still use DVM, oscilloscope and a soldering iron). The firmware disassembly is also no problem, I have the software to do it and I still occasionally write some simple programs myself.

As for no computer room wiring, I use the computers in more than one room and don't want to drag an ethernet cable all over the place or have points in every room when I have occasion to repair a computer (mine or someone else's) and using WiFi works for me.

The fibre-phone option (The NBN termination box has two RJ11 sockets) is charged at  a monthly rental plus calls just like a normal copper-wire telephone line whereas the VOIP is free (including all calls) with my ISP. The caller ID works just fine on the SPA122 and I don't need a separate switch.

Using the IVR 201 code simplifies the way I make changes (e.g. altering tones etc.) when necessary as I don't need to do a factory reset and restore the configuration each time.



still use DVM, oscilloscope

still use DVM, oscilloscope and a soldering iron

Oscilloscope and soldering iron is powerful hacking tool. I like them as well.

The firmware disassembly is also no problem

Firmware image is distributed in encrypted form, as far as I know. Thus it may not be easy to get even compiled but unencrypted form suitable for disassembly. May be it can be fetched using JTAG from device itself, but I never tried it.



Don't think I'll worry about

Don't think I'll worry about the IVR codes.

If somebody already has them they can send them to me (obviously someone already knew the 201 code).

Had a look at JTAG and it's out of my price range (pensioners don't get much).



May be a misunderstanding

May be a misunderstanding occurred.

I assumed you are familiar with IVR codes described in device's documentation and your's question is related to the undocumented ones.

So sorry if my assumption has been wrong. In such case this document may be answer to your original question.

Edited: you mentioned undocumented codes explicitly, but I missed it for now.



Never saw 201 in that picture

Never saw 201 in that picture before, must have missed it.

None of the PDFs (Installation, Provisioning or Administration) have all the codes, only the basic ones. At least not in the PDFs I have.

Because of this, I assumed it was undocumented.




By the way, IVR should be

By the way, IVR should be considered as initial and last-resort configuration mechanism only. For "home use" the WWW UI should be considered most important method of configuration. For techies and professional use the configuration via provisioning file (either XML or native format).

If you are interested to discover undocumented features, then I wish the IVR have little or no secrets. Most of secrets I expect within provisioning file. Also, so called S.O.S Firmware Recovery Protocol may be capable to do more than just firmware recovery.

But note the SPA phone can do cryptography. Thus some options may be recognized with provisioning file if signed or encrypted by special key only.



Thanks for the info. I will

Thanks for the info. I will look into it.