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NowSMS Support Forums ⬆ NowSMS Support - SMS Issues ⬆ Archive through September 15, 2003 ⬆ |
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| Author | Message | |||
| Matthieu |
When I send a SMS of more than 160 char. from the WEB interface, the MS gets all the SMS and is able to reassemble the entire text in one SMS but the text is junk characters? MT MMS which uses SMS notification that are longer than 140bytes works well though...maybe because those SMS notification are binary format SMS as opposed to regular text SMS. There is a setting on the T68i for long SMS which is enabled. Any clue? Thanks | |||
| Bryce Norwood - NowSMS Support |
Matt, This is probably an SMSC issue. We've been fighting an issue with some UCP/EMI SMSCs where long text messages appear as garbage on the receiving handset ... which sounds similar to what you are experiencing. I seem to recall that you're using SMPP, but just for the sake of others that might be reading this ... if you are experiencing this problem with a version later than v4.20, try manually editing SMSGW.INI, and create a section titled [UCP] in the file. Under that section header, add the statement: LongSMSTextEncoding=Yes At present, v4.20 is the current release, so if you want to try an update with this setting for UCP/EMI SMSC connections, please e-mail nowsms@now.co.uk. Now back to Matt ... There is some ambiguity in how this should be handled in the SMPP specification (well, under SMPP v3.4, you could send a long message to the SMSC in a single transaction using the message_payload TLV instead of the short_message parameter, but we found this was not very widely supported). So if you're sending a multipart 7-bit text message ... the issue is that if a message includes UDH (user data header), how should the text be encoded? At the raw SMS PDU level, 7-bit text always gets encoded to pack 160 characters into 140 bytes. With a long SMS, at the raw SMS PDU level, you need to start off with a UDH for concatenation, and then follow with 7-bit text encoded into the rest of the PDU. Now to the ambiguity of how this is done in the SMPP environment... In an SMPP environment, when you submit a 7-bit text message, the text is not compressed, it is submitted with each 7-bit character taking up an 8-bit byte in the SMPP submit. When you submit an 8-bit binary message, the data is encoded byte for byte as is in the SMPP submit. The SMSC, when it receives the SMPP submit, determines how to interpret the received data based upon the data_coding field. (Because if the data is 7-bit data, the SMSC is going to have to encode it to send it out to the mobile.) So, here comes the confusing part. Say you have a 7-bit text message that includes an 8-bit binary UDH (this doesn't just happen with concatenated messages, it also happens with EMS, as EMS uses the UDH). How should such a message be encoded? Our experience has been that you set the esm_class field to indicate that a user data header is included. The data_coding field is set for 7-bit encoding. The short_message field contains the binary UDH, followed by the 7-bit text in encoded format. I can't say that I've seen this behaviour explicitly spelled out anywhere, but our experience has been that if the data_coding field is set for a binary type, or the esm_class field indicates that a UDH is present, then the SMSC assumes that the short_message content is in binary format. As you have your own SMSC, and your own SMPP implementation to go along with it, I'd be interested to hear your perspective on how this should be handled. Keep in mind that UDH is used not just with concatenated messages, but also with EMS messages that contain text. It might be interesting to send a long SMS or a simple EMS from the T68i into a phone number that the SMSC would route the message over SMPP to NowSMS to see how your SMSC encodes these types of messages when delivering them over SMPP. -bn | |||
| milan |
Hi Bryce, I have experienced the same problem as Matt did. I use UCP/EMI connection to the T-Mobile CZ SMSC. I have just downloaded the current trial version (4.20), I have also added the [UCP] section to the SMSGW.INI file. Receiving MT is Siemens S45, S55 or Nokia 3310, but I still can only receive a garbage instead of a concatenated long text SMS. Have you got any idea ? Thanks a lot. | |||
| Bryce Norwood - NowSMS Support |
Hi Milan, That setting is not included in the v4.20 release. I believe that it is present in the updated build of v4.20 that can be downloaded at: http://www.nowsms.com/download/nowsms420a.exe Or, you can download the v5.0 beta release at http://www.nowsms.com/beta5, which definitely implements the described UCP setting. -bn | |||
