Multimedia messages on BT SAP, what happens to them?

[amwebby]

If I'm in the car with th phone connected by BT SAP and someone sends me a multimedia messag, it shows up in COMAND as "NO TEXT MESSAGE". When I check my SIM messages there's nothing there and niether is there anything in my inbox. What happens to them and is there any way of retrieving them?

 

[Diesel Benz]

I've seen this and concluded that the message is lost. But for some time I thought the same about SMS messages until I figured out those are available from the SIM.

The MMS push message (what ever it officially is) appears to be a specific text message that can be used only once, or perhaps it is an issue with reading the push message from the SIM card (is it a single message or is it sent in two parts, Comand anyway does not support message concatenation). Honestly I don't care a lot, I don't receice MMS messages often but it would still be nice if someone could find a solution to this issue.

 

[amwebby]

I didn't care either, never having received one before. Now O2 is my broadband provider I get 500 "webmails" a month, which means they send an MMS to my mobile every time an email is sent to my O2 email account. I find this very useful as I spend a lot of time travelling between clients and away from a free internet connection.

I think you're right about split messages as I received two "NO TEXT" messages but there was only one email in my inbox when I got home.

 

[amwebby]

A bit of Googling has thrown up the interesting fact that I can request a 3G SIM from O2. As I already get a 3G signal whem available it would appear the card isn't necessary for 3G reception.

As MMS is a 3G protocol is it possible the card will offer the storage necessary for such messages and will it work with BT SAP?

 

[Diesel Benz]

A bit of Googling has thrown up the interesting fact that I can request a 3G SIM from O2. As I already get a 3G signal whem available it would appear the card isn't necessary for 3G reception.

As MMS is a 3G protocol is it possible the card will offer the storage necessary for such messages and will it work with BT SAP?

MMS does not need 3G at all, just GPRS (which is available from GSM as GPRS or EGPRS or from UMTS/HSPA).

The approach is to send an SMS from the network because the mobile may not be GPRS attached and the network cannot reach the mobile then, the mobile needs to reach the network and this SMS gives the info for the mobile to activate the packet data connection accordingly.

I have a 3G USIM card in my phone but the main difference is that it supports multiple phone numbers per SIM phone book entry and 3G security. In practise all neworks allow UMTS access with an old GSM SIM card. I've seen talks about allowing MMS messages to be stored on the SIM card but as far as I know, this has not been implemented. The point is that MMS messages have an almost undefined size, is it some 1 MB that is allowed today and the SIM card would not have room for such messages.

The BT SAP device does not support UMTS but that is not the real issue with MMS. The real problem with these Peiker adapters is that they do not support GPRS and they have no means to retrieve the MMS message even if they receive the SMS notification for the MMS message.

The detail I would like to understand is how the SMS notification is constructed and how it could be properly rebuilt and used from the phone once the BT SAP adapter saves the message to the SIM card.

 

[amwebby]

Thanks for the clarification and explanation DB. That'll teach me to surf the web on a mobile phone at 04:15! Of course it was the 3GPP that developed MMS.

You're right about the BT SAP module not being able to retrieve an MMS, my hope was that a 3G SIM could retain the original message requesting the MMS content. Sadly I don't think that is the case if you have a 3G card and have experienced the same as me. My fear that the Peiker module wouldn't work with a 3G SIM appears to be allayed by your experience however.

Last night I discovered an SMS on my SIM and copied it to my phone's inbox. The two "NO TEXT" messages I had seen on COMAND earlier, but couldn't see on the SIM card, were also copied across. In the inbox they appeared with a message telling me I had received an MMS but it was unrecoverable.

 

[amwebby]

I've discovered a workaround of sorts in an O2 Bluebook account. This saves a copy of all SMS and MMSs sent to and from my phone on a server. It doesn't help my email alerts quandary but at least if someone sends me an MMS while I'm in the car in future it won't be lost.

The mangled versions on the SIM card appear to remain there even though I can't see them. Every time I access my SIM messages a "permanent-message-not-found" SMS appears in my inbox. I'm going to have to try deleting them from COMAND.

 

[amwebby]

Update. I received a new USIM 3G card from O2 yesterday. Today, whilst I was out in the car, one of those pesky MMS arrived. When I got back home I checked my SIM Messages and, as before, there was nothing. As soon as I backed out of the SIM folder I received the MMS! It was the same message. I know because a copy was stored in my Bluebook. :bannana: