Visual Voice Mail Configuration

AlainW94

Hi to all, I'm currently writing an application that will handle the visual voice mail for our favorite OS. The app will allow you to hear your voicemail messages and to see them as a list in the dialer-app.

But at that time, I would like to share with you how I did to configure it in Dekko2.

What is visual voice mail ?
Usually when someone could not reach you, he can leave you a message in your voicemail box, you have then to call your box a listen the message (and delete it using a number on your keypad).

The visual voice mail (vvm service) is a service that need to be activated for your account from your provider interface (call or web). This service require a data connection. When a people will not be able to reach you and leave you a message, your provider will send a hidden sms to your device (SMS CLASS 1 or 0) to inform a local application on your device about the need of download the message from an imap (mail) server. When you activate this service, your provider will send a hidden SMS to your device with your credential's information (imap server address, port, login, password), a dedicated app on your device will store it in a database.

I'm trying to write the app that will handle all of that but for now, I will try to explain to you how you can receive this SMS and try to configure Dekko2 (yes I said try because it was a kind of magic to get it to work) with the imap informations for getting your voicemails inside.

Configuration
First, you will have to active the debug on ofono (the process on our devices that handle sms and other things related to the cellular phone modem), to do that, put your file system in read write :

sudo mount -o remount,rw /

edit the file : /etc/init/ofono.conf

sudo nano /etc/init/ofono.conf

add this lines before the 'exec' line :

env OFONO_RIL_TRACE=y
export OFONO_RIL_TRACE

Restart your phone.

Now run the following command (via adb or terminal) :

tailf /var/log/syslog |grep ofonod

it's time to activate the vvm service from your account.
Once activated, wait and look in this logs for a UNSOLICITED SMS arrival, you should see something like that :

Mar 25 22:33:06 ubuntu-phablet ofonod[2593]: [1,UNSOL]< UNSOL_RESPONSE_NEW_SMS {07913xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxB0D}
Mar 25 22:33:06 ubuntu-phablet ofonod[2593]: SMS
Mar 25 22:33:06 ubuntu-phablet ofonod[2593]: ME Download message ignored

Copie the content located between the {}, it is the binary content of the SMS in PDU format. We will now use an online PDU decoder to have our SMS in clear text.

Go on this site :
https://www.diafaan.com/sms-tutorials/gsm-modem-tutorial/online-sms-deliver-pdu-decoder/

Paste your hexadecimal content in the "SMS DELIVER PDU" box then click on Decode.

In the table under, you will have the clear text message in front of the "Message" item. read this line, inside you will find all the needed information to connect to your imap provider, you will need those information :

srv or server= your imap mail server !
ipt or port = the port for the imap connection (ex 993 or 143)
u or name = your user name
pw = your personal password.

Now you are ready for configuring Dekko.

You can put your file system again in read/write mode and disable the ofono log by removing the two lines added before, the reboot the phone.

Configuring Dekko

To access the imap server of your provider, you have to switch off your wifi connection, the connection must be done via the cellular modem, so, switch off your WiFi for now.

Open Dekko and go to the settings to add a new account, choose IMAP, name it VVM or whatever you want, enter a description.
Your email address is your username@your_domain_provider ex: 123456@vvm.sfr.net, enter your password then click next. AND then come the magic ...

You have to know that in a normal working way, your device have to send a sms to your provider that tell the service is ready to be used on your phone. I didn't do that. I just try to connect with Dekko and after some hours (maybe the activation time), it downloaded the list of messages. You will have to play in the settings with the kind of crypting (SSL/TLS), the authentification way (I used LOGIN), maybe to manually enter the name of the INBOX in the folders options ... don't put a refresh time to short (I setup a check every 50 minutes or less but not every 5 minutes) normally your provider will expect a connection of your device when somebody leaves you a message, my provider seems to be more tolerant and the server accept my connection all the time.

It works well for me like this way but it is really provider depend. it could not be a success for everyone.

Here some screenshot from my Dekko (in French )

I hope that it will be usefull for some of you at least.

Alain

joe

This is intriguing. Thanks for sharing. How were you able to get audio attachments to show in Dekko2? Perhaps it's just some attachments that don't show up...for me it's mp3 attachments that I can't get.

AlainW94

@joe Hi, I did nothing special, Dekko2 was able to show this file as an attachment natively on my device, I'm also able to download it and to listen it. Normally the default format for VVM is AMR but as described in the OMTP protocol, this format should be asked by the mail client in the capability command (from memories). As Dekko is not made for VVM, this capacity is not sent to your provider, then it decide the format for you. An other thing is that from my provider portal, I can choose between activating VVM service for iPhone or Android, I chooses iPhone. The protocols are totally different, it can also be the cause why you get a mp3 not an amr. In my app, I'm trying to handle those 2 protocols.

joe

Thanks for the info. I'm using a different vm service.
I think it's a limitation of Dekko right now depending on the type of attachments.