CISCO 7941 help needed

We are considering moving all our business over to VoipFone.

However we have 10 7941 handsets that I need to get working with the network.
These have all been successfully converted over from SCCP to SIP 9-4-2 -1S and now I am just struggling with the correct config for VF now.

With a trial account, I can get a dial tone but the phone is clearly not registering with VF yet.

I have seen various threads on here but no conclusive solutions.

Has anyone managed to get the 7941 (or 61) to work with VF?
(I believe the 61 is very similar as it also uses XML)

Many thanks in advance for any pointers or sample configs.

Re: CISCO 7941 help needed

I believe It's because of Symmetric NAT.

You will either have to use your own PBX, or sell them and get something along the lines of the Snom 300 which are going cheap on ebay.

How many simultaneous calls will you be making? If you go down the route of running your own PBX I would recommend getting a Raspberry PI2 and put RasPBX on the thing, create a Voipfone trunk and register the Cisco 7941's to the RasPBX.
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Re: CISCO 7941 help needed

Correct as someone else pointed out on another forum the Cisco 7941 IP phones send SIP messages from arbitrary high number UDP ports (49000+ as you pointed out above) turns out that the symmetric NAT approach used by Asterisk (nat=yes) and most VOIP providers does not work with these phones. The Cisco 7941 IP phone will transmit ICMP unreachable messages back to SIP proxies that attempt to respond to SIP registration using symmetric NAT (you will see inbound SIP messages from the proxy with a high number UDP port destination, assuming your router works with symmetric NAT).

The behaviour is RFC compliant, just incompatibly non-standard. Cisco support reports that this the use of random high number ports to send SIP messages is a "security enhancement" compared with Cisco's other/older products.

I would sell them on and use the funds to purchase some second hand Snom's of eBay unless of course your budget allows you to purchase new. If you purchase them from Voipfone they come pre-configured out of the box.
All our telephones and adapters are pre-configured with UK ring and dial tones, our own optimum network settings and your user account details – so you should be able to just plug them into your home or office network and and start making calls straight away.

Once installed, all our equipment is auto-provisioned; this means that we can remotely adjust its setting to keep it up to date or perform remote diagnosis and maintenance if required; this ensures that your hardware is running at its best all the time.

Unlike some service providers who lock their telephones and adapters, you can change our configuration if you wish and it will work with other providers.

Because we pre-configure your device with your own username and password plus all the Voipfone and UK phone settings before we send it to you, your packaging will have been opened.
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Re: CISCO 7941 help needed

Many thanks Welshpaul, I'm quite depressed about that!

To be honest it was developing into an intellectual challenge - I just hate it when I can't get something to work.
We are migrating from Voicenet or whatever they are called now. The second hand market for the Ciscos doesn't look so great,

We are also running a couple of Siemens Gigaset c430s with another operator so I am just about to try hooking these up to my Voipfone trial account.

We are a bike tour operator with teams scattered all over Europe. The smartphone app actually works ok but can be a bit flaky thus we have 7941s in the support vehicles so that they can be deployed on long hotel stay overs. I found a nifty way to plug them up using a wifi connected laptop. One might think it is a bit of overkill but much more convenient than a mobile when you have a load of calls to make with clients and to the office.

In the light of the demise of the 7941s, I need to research what might be a more appropriate handset. They are very chunky and need a PSU when operating without PoE .

Do you know if there is Voipfone limit to the number of extensions that can be deployed behind a single router?

Many thanks for all your help.

Re: CISCO 7941 help needed

aztecboy wrote:The second hand market for the Cisco's doesn't look so great
I did check out ebay and your right! They go for silly money.
aztecboy wrote:We are also running a couple of Siemens Gigaset c430s with another operator so I am just about to try hooking these up to my Voipfone trial account.
Voipfone do support this make/model, they sell them on their online store. :)
aztecboy wrote:Do you know if there is Voipfone limit to the number of extensions that can be deployed behind a single router?
You can have up to 800 extensions on each Voipfone account and each extension can be called 'internally' by dialling its three digit short code. There is no Voipfone imposed limit to how many of those 800 extensions you can use behind a single router. :)
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