Clickatell Platform gives you the option to specify in which character set you are submitting your messages. If the charset is not specified, all messages will be encoded in the UTF-8 Unicode standard by default. The UTF-8 library covers almost all written characters and symbols for all major languages. It was also designed for backward compatibility with ASCII.

A large number of mobile networks support only the GSM character set. The GSM character set is much smaller than UTF-8, so it’s possible that some characters may not be supported.

Our system was developed to automatically determine the encoding needed for the optimal delivery of an SMS message. If any characters in your submitted messages are not supported by the mobile network carrier, we will automatically convert the message to the hexadecimal Unicode format required to ensure delivery.

We therefore fully support Unicode encoding with no effort from your side, we do it automatically for you. Messages should be submitted to our platform in a text (unconverted format), we’ll handle the Unicode conversion for you when required.

If a message is converted to the hexadecimal Unicode format, fewer characters can be accommodated per message part. With this format, message parts consist of only 70 characters.

Learn more about how multiple message parts (concatenation) works, here.

To test whether your server is TLS1.2 compatible, perform these instructions from a Linux desktop.  

Alternatively, here are versions of Operating Systems and Applications that commonly support TLS1.2: 

Windows  

• Windows 7 

• Windows Server 2008 R2+ 

 
Linux 
Linux applications are primarily dependent on the OpenSSL version installed. The examples provided are platforms where the default OpenSSL included is sufficiently new:  

• Ubuntu - 12.04 (Precise) or better 

• Red Hat / CentOS - v6+ 

• Debian - 7.0 (Wheezy) 

 
OpenSSL 
This needs to be at least version 1.0.1. 

 
.NET 
Version 4.6 defaults to TLS 1.2. Version 4.5 and below require a specific flag for TLS to be set, however, for versions below 4.5 your system will still need .NET 4.5 Installed to support TLS 1.2. 
 
Java 
Version 8 (1.8) defaults to TLS 1.2. Java 7 (1.7) needs to be told to use TLS 1.2. 
 
PHP/Ruby/Node.js 
These rely mostly on OpenSSL to handle TLS needs. Check that your version of OpenSSL is at least 1.0.1. 

Our standard integration will support all characters in the GSM character set. Any message created on a standard Western-language keyboard will be supported by our system. If you configure your integration definition settings (from your dashboard) for Unicode messaging, it will handle all the characters supported by the UCS2 set.