Network entity, method and system for invocation of supplementary services across different networks

A method for providing supplementary services offered by a second network to a mobile device while the mobile device is roaming in a first network, the method comprising:

• receiving a first message from a mobile device being provided roaming service by the first network, the first message being conformant to a protocol supported by the first network for invoking supplementary services and having embedded therein an invocation message for invocation of at least one supplementary service offered by the second network;
• extracting the invocation message from the first message;
• sending the invocation message to the second network using a protocol used by the second network to invoke the at least one supplementary service;
• receiving a reply from the second network in the protocol used by the second network to send a response to a request to invoke the at least one supplementary service;
• embedding the reply into a second message in a transport protocol supported by the first network;
• and
• sending the second message to the mobile device in the first network using the transport protocol,
• wherein the invocation message is in a format usable by the mobile device for directly invoking the at least one supplementary service offered by the second network when the mobile device is being provided non-roaming service by the second network,
• wherein the at least one supplementary service offered by the second network supports at least the functions:
• enable supplementary service, disable supplementary service, and query supplementary service,
• wherein invoking the at least one supplementary service comprises triggering any one of said functions, and
• wherein the protocol supported by the first network for invoking supplementary services differs from the protocol used by the second network to invoke the at least one supplementary service.

A system for providing one or more supplementary services offered by a second network to a mobile device while the mobile device is roaming in a first network, the system comprising the mobile device and a network entity, wherein:

• the mobile device comprises:
• a user interface to receive input for invocation of at least one of the one or more supplementary services offered by the second network;
• a first converter for embedding an invocation message based on the input into a first message in a transport protocol supported by the first network;
• and
• a first output to send the first message to the network entity through the first network;
• and
• the network entity comprises:
• a receiver for receiving the invocation message from the mobile device;
• a second converter for extracting the input from the first message;
• and
• a second output for sending the invocation message to the second network using a protocol used by the second network to invoke the at least one of the one or more supplementary services,
• wherein:
• the mobile device is configured to embed the invocation message into an SMS message;
• the receiver of the network entity is further configured to receive a reply from the second network;
• the second converter is configured to embed the reply in a second SMS message;
• and
• the second output is configured to send the second SMS message to the mobile device in the first network;
• and wherein:
• the mobile device further comprises a receiver for receiving the second SMS message;
• the first converter is further configured to extract the reply from the second SMS message;
• and
• the mobile device is further configured to process the reply.