Abstract: A method for transaction authorization with the use of a mobile phone, comprising the steps of receiving (102, 202) from the user (UR), by the communication server (CS) a voice call establishment request, to establish a voice connection to a telephone number which identifies a transaction; authorize the transaction by verifying (112, 206) the credentials of the user (UR); accepting (106, 214) or rejecting (108, 216) the voice call; sending a request (116, 220) to the user (UR) to enter necessary transaction parameters; entering (118, 222) the requested transaction parameters; verifying (120, 224), by the authorization system (AS), the validity of the entered parameter; determining (122, 226) whether the user (UR) has entered all necessary transaction parameters, including user's authorization to fund the transaction and, preferably, a password authorizing the transaction; accepting the transaction funding by the transaction party responsible for it (124, 228), and, if the amount has been accepted, sending a m

Abstract: A method for transaction authorization with the use of a mobile phone, comprising the steps of receiving (102, 202) from the user (UR), by the communication server (CS) a voice call establishment request, to establish a voice connection to a telephone number which identifies a transaction; authorize the transaction by verifying (112, 206) the credentials of the user (UR); accepting (106, 214) or rejecting (108, 216) the voice call; sending a request (116, 220) to the user (UR) to enter necessary transaction parameters; entering (118, 222) the requested transaction parameters; verifying (120, 224), by the authorization system (AS), the validity of the entered parameter; determining (122, 226) whether the user (UR) has entered all necessary transaction parameters, including user's authorization to fund the transaction and, preferably, a password authorizing the transaction; accepting the transaction funding by the transaction party responsible for it (124, 228), and, if the amount has been accepted, sending a m

Abstract: A method for providing services in a telecommunication network with the use of USSD channel, comprising of a step of receiving (102), by a terminal device (DT), a call establishment request for a voice connection from an initiating terminal with a recipient's telephone number,—a step of rejecting (108) the call establishment request for the voice connection, if the call establishment request is determined (104, 106) to be a request for USSD based services. In subsequent steps information about the rejected call request is transmitted (110) from the terminal device (DT) to a server (GTW), the information including at least the telephone number of the terminal (OT) initiating the voice connection, and in the following steps the server (GTW) establishes (112) a USSD session and initiates (114) an exchange of messages from the server (GTW) via the USSD channel.