Abstract: Acquisition portion acquires distribution rule information, user situation information, and a distribution information structured document output from contents distribution server, and evaluation object extraction portion extracts evaluation objects related with the user side situation from evaluation objects of each condition description portion contained in the distribution rule information, and user situation extraction portion extracts the situation of user terminal corresponding to evaluation objects concerned from the user situation information, and condition evaluation portion evaluates each condition description portion on the basis of the situation of the user terminal, and conversion rule information generation portion generates a conversion rule information on the basis of the result of the evaluation, and conversion portion converts a distribution information structured document on the basis of the conversion rule information, and output portion outputs the distribution information structured docu

Abstract: A delay unit 103 adds holding time that has been set by a holding time setting unit 104 to a received data. The holding time is computed based on delay time of received data and the minimum delay time of data received up to a certain point for the purpose of reducing a total delay time. The delay time is estimated in a delay time estimating unit 106 from the difference between a reception time of a packet counted based on an internal clock generator 107 and a time designated by a time stamp in the received packet.

Abstract: A gateway for interconnecting two networks, comprising a receiver, a controller, and a transmitter. The receiver receives from a first network a plurality of data units in all least one form. The controller temporarily stores the data units received by the receiver and outputs the data units on the basis of the dejitterizing capability of a destination terminal served by a second network, thereby reducing jitter among delays of the data units. The transmitter sends data units corresponding to the data units output by the controller to the destination terminal through the second network.

Abstract: Acquisition portion acquires distribution rule information, user situation information, and a distribution information structured document output from contents distribution server, and evaluation object extraction portion extracts evaluation objects related with the user side situation from evaluation objects of each condition description portion contained in the distribution rule information, and user situation extraction portion extracts the situation of user terminal corresponding to evaluation objects concerned from the user situation information, and condition evaluation portion evaluates each condition description portion on the basis of the situation of the user terminal, and conversion rule information generation portion generates a conversion rule information on the basis of the result of the evaluation, and conversion portion converts a distribution information structured document on the basis of the conversion rule information, and output portion outputs the distribution information structured docu

Abstract: Service procedures and/or message formats such as encryption and attachment of a digital signature are properly used according to an available amount of money defined in a certificate of service, network environments such as intensity of security, transmission band and locations of communication paths and operation policy, whereby the system enables to shorten service providing time, to adjust the intensity of security and to reduce the amount of information transmitted through the information network. It is preferable to encrypt a part of the information or to attach a digital signature to the part of the information, instead of encrypting all information or attaching the digital signature to all information. Consequently, encryption of only the important portion of the information can be available.

Abstract: A delay unit 103 adds holding time that has been set by a holding time setting unit 104 to a received data. The holding time is computed based on delay time of received data and the minimum delay time of data received up to a certain point for the purpose of reducing a total delay time. The delay time is estimated in a delay time estimating unit 106 from the difference between a reception time of a packet counted based on an internal clock generator 107 and a time designated by a time stamp in the received packet.