Method for establishing resource access authorization in M2M communication

A method for establishing an authorization to access resource in Machine-to-Machine (M2M) communication, when an entity selected from a terminal, a gateway and an end user as a client in an M2M service provider domain attempts to access resource located in a terminal or a gateway in the same M2M service provider domain, the method comprising:

• receiving by the client a client credential allocated from an authentication server for providing an authentication service in the M2M service provider domain by performing a client registration to a service layer of an M2M server for providing an M2M service which is required in the M2M service provider domain;
• requesting an authorization to access the resource to a resource owner of the resource through the service layer based on information about a Universal Resource Identifier (URI) of the resource by the client;
• verifying by the resource owner the client through the authentication server;
• granting the authorization for the client to access the resource by the resource owner;
• issuing an access token to the client by the authentication server in the M2M service provider domain, and
• accessing by, a processor of the client, the resource based on the issued access token.