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<concept id="GUID-DF114F59-4DC9-5C77-B7F9-F1C93B8E714C" xml:lang="en"><title>SMS

Encoding and Decoding</title><shortdesc>This section describes the SMS encoding and decoding concepts.

The encoding and decoding of the SMS messages is done in the SMS stack. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The GSMU of the SMS stack provides the relevant methods for encoding and

decoding the messages. The character converter (CharConv) components provide

the plug-ins required and the mapping table for encoding and decoding. </p>

<section id="GUID-FC24C6B7-1CC7-5D95-826D-18AAFB627753"><title>Encoding</title> <p>The

default method for encoding is 7 bit method. Some languages contain the characters

based on Latin but with additional accented characters, these accented characters

cannot be encoded using the 7 bit converters. The default 7 bit encoding method

allows 160 characters per SMS message. 8 bit encoding is also possible. The

8 bit encoding supports 140 characters in a message. The additional characters

can be supported in two forms: </p> <p><b>Unicode </b> </p> <p>The accented

languages can be encoded using 16 bit Unicode. The disadvantage of using Unicode

is that it limits the message data to 70 characters. Unicode encoding leads

to increase in cost for the end user. For example if a user sends a message

with 100 characters using Unicode encoding will require two separate SMS messages

instead of 1 message using 7 bit encoding. </p> <p><b>Alternative encoder </b> </p> <p>The

second method available to support the accented Latin based characters are

to use alternative encoder which perform a Lossy conversion. In Lossy conversion

the accented characters are encoded to the nearest GSM character. For example

Á is encoded as A. For more information see <xref href="GUID-FE94596E-B5BB-51FE-BE38-069840323915.dita#GUID-FE94596E-B5BB-51FE-BE38-069840323915/GUID-918FF2E3-B9F4-5C61-8DBA-F9143DB16460">Lossy

7 Bit Encoding</xref>. </p> </section>

<section id="GUID-949DCFCD-9156-594E-828C-2C554C288C56"><title>Decoding</title> <p>Decoding

of SMS messages does not require any alternative converter as the existing

converter can decode 16 bit Unicode characters. If the incoming message is

7 bit encoded, there is no loss of information. </p> </section>

<section id="GUID-8752F0EC-90F3-578C-823D-8B569684BF79"><title>National Languages</title> <p>Some

of the national languages supported are: </p> <ul>

<li id="GUID-02E9DFC9-6A19-52CA-B981-78FD06B8B11C"><p>Turkish </p> </li>

<li id="GUID-02E0BC2A-B978-573D-8E50-1012EC3F809A"><p>Spanish </p> </li>

<li id="GUID-ED89406B-2B9C-5635-9F12-895FB714FBFB"><p>Portuguese </p> </li>

</ul> <p>These national languages can be identified using the enumeration

in <xref href="GUID-989446D9-E161-3CCC-A0BA-E9340FF9157A.dita"><apiname>TSmsNationalLanguageIdentifier</apiname></xref>. </p> </section>

</conbody><related-links>

<link href="GUID-785701A4-615B-5590-91C6-FD29C56FB2E7.dita"><linktext>Using Alternative

Encoder</linktext></link>

<link href="GUID-FE94596E-B5BB-51FE-BE38-069840323915.dita"><linktext>Encoding

Types</linktext></link>

</related-links></concept>