Hi Andreas, Are you saying the concatenated SMS can be either 153 or 154 as it depends on the SMSC if it discards the last char?
If this is the case, which is interesting, we will need to test with each SMSC we use and keep a record if a concatenated message is 153 or 154 chars. Currently in testing a concatenated SMS allows 154 chars. Thanks for your insightful comments. -----Original Message----- From: Andreas Fink [mailto:[EMAIL PROTECTED] Sent: 31 January 2007 16:02 To: [EMAIL PROTECTED] Cc: devel Devel Subject: Re: are these bugs when sending concatenated SMSs This depends on send it where its being sent. Kannel does automatically split long SMS. Also it might be that your SMSC splits it or discards the last char. On 31.01.2007, at 12:50, Hillel wrote: Hi Andreas, But with Kannel you can send 154 characters in a concatenated SMS and are not limited to 153? Why is this the case? Thanks -----Original Message----- From: Andreas Fink [mailto:[EMAIL PROTECTED] Sent: 31 January 2007 12:40 To: devel Devel Cc: Hillel Subject: Re: are these bugs when sending concatenated SMSs Here's the exact calculation of the PDU splitting borders. On the wire and in the air, a SMS PDU always contains a maximum of 140 octets. Thats why you can pack 140*8/7 = 160 characters into an SMS. If a UDH header is used (udh indicator bit is set), then the beginning of the SMS-PDU contains the UDH (universal data header). The UDH is 6 octets for a splitted text sms. This leaves us with 134 octets remaining. 134 octets are 1072 bits. in 1072 bits you can pack 153 septets and you are left over with one spare bit. This is where the 153 character limits for split SMS comes from. On 31.01.2007, at 10:16, Alexander Malysh wrote: Hi, for 7bit (text message) kannel send 154 octets of text + 6 octets udh that give you 160 Octets together. SMPP doesn't pack because it's not necessary following the spec but SMSC packs then those. Am 31.01.2007, 09:41 Uhr, schrieb Hillel <[EMAIL PROTECTED]>: Hi, I've been looking at the spec 03.40 and I've also tested and 154 is the max amount of chars you can use before becoming another SMS. If I re-read the spec below with this information, can I assume Kannel is using compressed GSM Default alphabet 7 bit data and you always lose 6 octets to give you 134 octets left which translates into 154 chars.? (If it was using uncompressed GSM Default 7 bit data then you would only have 153 chars per concatenated SMS.) Is my understanding correct? 9.2.3.24.1 Concatenated Short Messages This facility allows short messages to be concatenated to form a longer message. In the case of uncompressed 8?bit data, the maximum length of the short message within the TP?UD field is 134 (140?6) octets. In the case of uncompressed GSM Default 7 bit data, the maximum length of the short message within the TP?UD field is 153 (160?7) characters. In the case of 16 bit uncompressed USC2 data, the maximum length of the short message within the TP?UD field is 67 ((140?6)/2) characters. A UCS2 character must not be split in the middle; if the length of the User Data Header is odd, the maximum length of the whole TP-UD field is 139 octets. In the case of compressed GSM Default alphabet 7 bit data, 8 bit data or UCS2 the maximum length of the compressed short message within the TP-UD field is 134 ( 140-6) octets including the Compression Header and Compression Footer, both or either of which may be present ( See subclause 3.9). The maximum length of an uncompressed concatenated short message is 39015 (255*153) default alphabet characters, 34170 (255*134) octets or 17085 (255*67) UCS2 characters. Thanks for your great response. Rgds -- Thanks, Alex Andreas Fink Fink Consulting GmbH Global Networks Schweiz AG BebbiCell AG --------------------------------------------------------------- Tel: +41-61-6666330 Fax: +41-61-6666331 Mobile: +41-79-2457333 Address: Clarastrasse 3, 4058 Basel, Switzerland E-Mail: [EMAIL PROTECTED] www.finkconsulting.com www.global-networks.ch www.bebbicell.ch --------------------------------------------------------------- ICQ: 8239353 MSN: [EMAIL PROTECTED] AIM: smsrelay Skype: andreasfink Yahoo: finkconsulting SMS: +41792457333 Andreas Fink Fink Consulting GmbH Global Networks Schweiz AG BebbiCell AG --------------------------------------------------------------- Tel: +41-61-6666330 Fax: +41-61-6666331 Mobile: +41-79-2457333 Address: Clarastrasse 3, 4058 Basel, Switzerland E-Mail: [EMAIL PROTECTED] www.finkconsulting.com www.global-networks.ch www.bebbicell.ch --------------------------------------------------------------- ICQ: 8239353 MSN: [EMAIL PROTECTED] AIM: smsrelay Skype: andreasfink Yahoo: finkconsulting SMS: +41792457333
