hellkvist.org

[smhs]

Hello,

my question is actually in the subject of this topic. I'm writing a software which works with GSM module GM47, connected through RS232. This module has GPRS support, and I am able to connect to the internet with it. What I need, is to send MMS through operators MMSC. How this should be done? As I see, an MMS message can be encoded with your library just fine. How should I communicate with my operators MMSC in order to send the MMS? Here are the parameters they gave to me:
Configurable parameters:
Data: GPRS
Access point name: gprs.mms.lt
Connection method: secure
Username: mms
Password: mms
IP address: 194.176.32.149
MMSC website: http://mms.omnitel.net:8002/

Does it mean, that I have to connect to MMSC as to ordinary webserver and pass encoded MMS to it using HTTP POST or something like that? I suppose that the server will not recognize the number of who sends that MMS and thus will not accept this MMS.In this case I have to communicate through WAP GW, but I have no clue how this should be done?

I'm just getting lost among all those specifications and documentation about MMS, WAP and so on.

Thank you.

[smhs]

It seem to be that I should connect to 194.176.32.149 on port 9201 and send UDP packets with some data encoded, which is documented in document WSP-230? Right?

[Peffis]

From a phone MMS is sent by encoding an MMS with content (see for instance mmslib on http://hellkvist.org/software ) and then posting it to the MMSC with an HTTP POST. Phones however uses WAP to achieve this, thus they do the post towards the MMSC by doing a WAP POST (which is UDP packets as you say) through a wap gateway. I think your best bet on getting the right settings for your sim card is to put it in a phone, browse to your operator's site and ask them to send out OTA (Over The Air) settings for your sim card. You will receive this in an SMS. Then you just write down the settings you have on the phone, such as wap gw and MMSC URL and you will have to try to encode the MMS and send it towards the MMSC URL using WAP POST with the wap gw. Accessing the MMSC directly with an HTTP POST would most likely not be possible.

[smhs]

Thank you for your reply, Peffis.

I found that the scenario of sending MMS message manually through a WAP GW consist these next steps (for those, who also have a question like mine was):

WSP Connect, the GW should reply with WSP ConnectReply,
WSP POST <MMS encoded>, the GW should reply with WSP Result
WSP Disconnect.

All WSP methods (Connect, Post etc) are encapsulated in WTP packets of type INVOKE class 2, the packets received from GW are the packets of type Result, your duty is to acknowledge all WTP Result with WTP ACK packets. WTP packets are transmitted over WDP (which is UDP in case when using IP as underlying protocol). Segmentation-and-Reassebly is also handled by UDP/IP stack, so segmentation/reassembly mechanism provided by WTP is not neccessary, however I'm no sure, if GW indeed wont send you segmented WTP packets.

If one need to send MMS through operators GW should implement WTP/WSP stack. WTP/WSP specifications are freely available at OMA (open mobile alliance).

Yes, sending MMS through ordinary HTTP POST will not work in most cases (at least none of operators available in Lithuania, where I live,don't allow this), because mobile operators want you to pay MMS sending fee.

I also have found, that testing one's implemented WSP/WTP stack is convinient using KannelWAPGW/RbuniMMSGW, so you don't have to test your application with operators GW.