Abstract:
The present invention relates to a communication apparatus capable of using near field communication from various protocols, a communication method for use therewith, and a program for use therewith. NFC communication apparatuses 1 to 3 capsulize an LLC packet of an LLC layer of a data link layer in an MAC packet of an MAC layer, capsulize the MAC packet in a physical layer packet of a physical layer, and transmit and receive the packet. In that case, the maximum length of the LLC packet is limited so as to be smaller than or equal to a length that is determined on the basis of the maximum length of the physical layer packet and the maximum number of MAC packets that can be transmitted continuously from the MAC layer to the LLC layer without making a response. The present invention can be applied to, for example, an IC card system or the like.
Abstract:
The present invention relates to a communication system, a communication device, and a communication method for easily solving a problem of a hidden terminal. Communication devices 1 and 3 determine whether or not an electromagnetic wave at the level of a magnetic-flux density TH1 or more for determining the suppression of the output of carrier. When the electromagnetic wave at the level of the magnetic-flux density TH1 or more for determining the suppression of the output of the carrier is not detected, the communication devices 1 and 3 start the output of the electromagnetic wave. A communication device 2 needs the electromagnetic wave at the level of a magnetic-flux density TH2 or more of the carrier at an operating limit, which is higher than the magnetic-flux density TH1 for determining suppression of the output of carrier so as to obtain data via the electromagnetic wave. The present invention is applied to, e.g., an IC (Integrated Circuit) card system.
Abstract:
The present invention relates to a communication system and communication method which enable various types of near field communication, and a data processing apparatus. NFC communication apparatuses 1 to 3 have two features in that each can perform communication in two communication modes and that each can perform data transmission at a plurality of transfer rates. The two communication modes consist of a passive mode and an active mode. In the passive mode, between the NFC communication apparatuses 1 and 2, for example, the NFC communication apparatus 1 transmits data to the NFC communication apparatus 2 by modulating electromagnetic waves generated by itself, while the NFC communication apparatus 2 transmits data to the NFC communication apparatus 1 by performing load modulation on the electromagnetic waves generated by the NFC communication apparatus 1. Alternatively, in the active mode, either of the NFC communication apparatuses 1 and 2 transmits data by modulating electromagnetic waves generated by itself. The present invention can be applied to, for example, an IC card system, etc.
Abstract:
A tape driver using, as a recording medium, a tape cassette (1) containing a magnetic tape (83) and composed of cassette halves (6) having a memory (4). Before application data is recorded on the magnetic tape (3), the first portion of the application data to be recorded on the magnetic tape (3) is written in a region of a predetermined size of the memory (4). Thus, at least management information located at the first portion of the application data can be stored in the memory (4). When the application data is reproduced from the tape cassette (1), the time to access the management information recorded on the magnetic tape (3) is not required by using the management information stored in the memory (4), thereby increasing the speed of the access to the data recorded on the magnetic tape (3).
Abstract:
A recording medium adapter such as a library apparatus (50) for controlling individual recording media by a command by radio communication after authenticating a recording medium on the basis of identification information such as its serial number. A communication identifier such as a session identifier corresponding to the identification number of a recording medium is set and imparted to the recording medium. A command including the communication identifier is issued during the control. As a result, only the specific recording medium to be controlled is operated according to the command. In authenticating a recording medium, identification information such as a serial number, which is unique information, is confirmed and communicated reliably by using a temporary communication identifier, and several stages of communication are carried out, thus reliably authenticating the recording medium.
Abstract:
A communication device for performing near field communication, includes: a near field communication device having a near field communication section for performing near field communication in either one of an active mode and a passive mode, and an interface section for supplying the near field communication section with data from a data processing device for processing data targeted by communication of the near field communication section, and supplying the data processing device with data from the near field communication section; and one or more of the data processing devices connected to the interface section by one output bus on which the data output by the interface section is transmitted, and one input bus on which the data input to the interface section is transmitted, wherein the data processing device includes bus right management means.
Abstract:
The present invention relates to a communication system, a communication device, and a communication method for easily solving a problem of a hidden terminal. Communication devices 1 and 3 determine whether or not an electromagnetic wave at the level of a magnetic-flux density TH1 or more for determining the suppression of the output of carrier. When the electromagnetic wave at the level of the magnetic-flux density TH1 or more for determining the suppression of the output of the carrier is not detected, the communication devices 1 and 3 start the output of the electromagnetic wave. A communication device 2 needs the electromagnetic wave at the level of a magnetic-flux density TH2 or more of the carrier at an operating limit, which is higher than the magnetic-flux density TH1 for determining suppression of the output of carrier so as to obtain data via the electromagnetic wave. The present invention is applied to, e.g., an IC (Integrated Circuit) card system.