Is one of message forms via the Internet; you only have to press the
icon or button on the site and the connection with the operator will follow
immediately. This function is often used on the websites for a quick
connection.
Configurations
of GSM/VoIP networks allow the service providers to avoid the local Wired
Public Switched Network (PSTN) in communication with a GMS mobile handset. As a
result, the high rates charged by telephone companies are avoided.