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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>