Abstract: A packet processing apparatus includes: a plurality of storages configured to store packets for each high priority flow or low priority flow for each output port in the same group; a gate configured to open and close output of each storage; and a processor configured to: control opening and closing of the gate to preferentially output high priority packets of the high priority flow on the basis of gate information that controls the gate; calculate, for each output port, the theoretical number of collisions of the high priority packets in which arrival timings overlap between the high priority packets; distribute a high priority flow of a collision to another output port in the same group by a link aggregation scheme such that the theoretical number of collisions is reduced; and update contents of the gate information based on distribution contents.

Abstract: In a frame relay apparatus or a frame relay method, in order to be able to transfer data between channels having different maximum transfer units, payloads are fragmentized or combined and assembled into a frame, in response to the maximum transfer units of the channels. Fragmentized payloads are associated with the original data. By doing so, especially the number of frames in a channel with a large maximum transfer unit is controlled, and the transfer efficiency of frames of the entire network may be improved.

Abstract: A communication device for transmitting and receiving frames, which is capable of preventing an overflow of a buffer memory due to clock error even when the utilization factor of a transmission line is high. A frame holding section stores frames awaiting transmission. A transmission section sequentially takes out each frame from the frame holding section and outputs the frame to the transmission line, based on a control signal indicative of timing for transmitting the frame. A transmission control section initially outputs the control signal at a repetition period of T clocks (T?2) and acquires the number of waiting frames in the frame holding section every N×T clocks (N?2).

Abstract: In a frame relay apparatus or a frame relay method, in order to be able to transfer data between channels having different maximum transfer units, payloads are fragmentized or combined and assembled into a frame, in response to the maximum transfer units of the channels. Fragmentized payloads are associated with the original data. By doing so, especially the number of frames in a channel with a large maximum transfer unit is controlled, and the transfer efficiency of frames of the entire network may be improved.

Abstract: A communication system that includes a single subscriber line terminal on a network side, a number of terminal units on a user side, and a single transmission line shared thereby multiplexing through polling. In the communication system, a queue length extracting unit extracts from information stored for each connection, a parameter setting unit sets the contracted parameters of a sustainable cell rate and peak cell rate and contracted parameters of fluctuation values, a parameter managing memory stores the queue length information and the contracted parameter information, a bandwidth calculating unit re-stores results of periodic calculation of the cell rates so that the contracted parameters are observed, and a transfer polling information generating unit determines timings of transfer of information in accordance with the calculated allocated cell rates and outputting them.

Abstract: A method for time-division multiplexing including steps of generating a plurality of first signals and a plurality of second signals to which specific pulse trains for frame synchronization are allocated respectively; generating low speed signals of plural channels including the first and second signals and transmission signals; a conversion step; and time-division multiplexing the low speed signals after the conversion step, thereby obtaining high speed signals. When applied to SDH, for example, the first and second signals may be A1 bytes and A2 bytes respectively, and the transmission signals may ho payload signals. According to one aspect of the invention, at the conversion step, the first and second signals in each channel are panty convened into either of “1/0” alternating signals and “0/1” alternating signals. Consequently, it becomes possible to reduce the number of successive same code and to diminish the deviation of the mark rate.

Abstract: A communication device for transmitting and receiving frames, which is capable of preventing an overflow of a buffer memory due to clock error even when the utilization factor of a transmission line is high. A frame holding section stores frames awaiting transmission. A transmission section sequentially takes out each frame from the frame holding section and outputs the frame to the transmission line, based on a control signal indicative of timing for transmitting the frame. A transmission control section initially outputs the control signal at a repetition period of T clocks (T?2) and acquires the number of waiting frames in the frame holding section every N×T clocks (N?2).

Abstract: There is provided a communication system directed to inhibiting degradation of the efficiency of transmission of user information and improving the communication quality. A correspondence table management unit creates a correspondence table based on table forming information. A buffer status value acquiring unit acquires a buffer status value of a buffer that issues a transmission event. A notice information setting unit compares a size relation between status information about past buffer status values for the buffer and a current buffer status value acquired, and sets notice information on a bit basis. A terminal-side notice information management memory stores and manages the notice information as the status information. A notice information sending unit sends the notice information to notify an upper device of the buffer status. A table forming information sending unit sends the table forming information. A control-side notice information management memory receives and manages the notice information.

Abstract: A subscriber-line-terminating apparatus for dynamically allocating band portions to a plurality of terminal apparatuses includes an in-buffer-information-amount receiving unit for receiving an in-buffer-information amount from each of the terminal apparatuses; an insufficient-band-computing unit for computing an insufficient band portion required by each of the terminal apparatuses; an in-buffer-information-amount-proportional-band-allocating unit for allocating a band portion corresponding to the in-buffer-information amount to each of the terminal apparatuses and a past-use-band-allocating unit for allocating a past-use band part to each of the terminal apparatuses as a past-use band portion based on a first past-use band variable of the terminal apparatus.

Abstract: A communication system including a queue length extracting function unit extracting from information stored for each connection, a parameter setting function unit for setting the contracted parameters of a sustainable cell rate and peak cell rate and contracted parameters of fluctuation values allowed in these bandwidths for each connection, a parameter managing memory (43) for storing the queue length information and the contracted parameter information, a bandwidth calculating function unit for re-storing in the memory results of periodic calculation of the bandwidths allocated to connection so that the contracted parameters are observed, and a transfer polling information generating function unit (45) for determining timings of transfer of information in accordance with the calculated allocated bandwidth and outputting it as the polling information.

Abstract: The present invention provides a method for time-division multiplexing. This method comprises a step of generating a plurality of first signals and a plurality of second signals to which specific pulse trains for frame synchronization are allocated respectively; a step of generating low speed signals of plural channels including the first and second signals and transmission signals; a conversion step; and a step of time-division multiplexing the low speed signals after the conversion step, thereby obtaining high speed signals. When the present invention is applied to SDH for example, the first and second signals may be Al bytes and A2 bytes respectively, and the transmission signals may be payload signals. According to one aspect of the invention, at the conversion step, the first and second signals in each channel are partly converted into either of “1/0” alternating signals and “0/1” alternating signals.

Abstract: There is provided a communication system directed to inhibiting degradation of the efficiency of transmission of user information and improving the communication quality. A correspondence table management unit creates a correspondence table based on table forming information. A buffer status value acquiring unit acquires a buffer status value of a buffer that issues a transmission event. A notice information setting unit compares a size relation between status information about past buffer status values for the buffer and a current buffer status value acquired, and sets notice information on a bit basis. A terminal-side notice information management memory stores and manages the notice information as the status information. A notice information sending unit sends the notice information to notify an upper device of the buffer status. A table forming information sending unit sends the table forming information. A control-side notice information management memory receives and manages the notice information.

Abstract: The present invention relates to a line terminating equipment for allotting a transmission bandwidth to a plurality of terminals at one end of a subscriber line section of an access network. In the line terminating equipment, requisite bandwidths of the individual terminals are computed as an increasing function of receipt information content which is content of transmission information precedingly received from the terminals and untransmitted information content notified by the terminals. The transmission bandwidth to be allotted to each terminal is determined in a manner which is decided according to a comparison result of magnitude between a total requisite bandwidth and a transmission bandwidth of a transmission channel. Therefore, in a communication system to which the present invention is applied, the transmission bandwidth is allotted effectively, flexibly, and efficiently to all the terminals, which enhances total reliability as well as service quality and transmission quality.

Abstract: A subscriber-line-terminating apparatus for dynamically allocating band portions to a plurality of terminal apparatuses includes an in-buffer-information-amount receiving unit for receiving an in-buffer-information amount from each of the terminal apparatuses; an insufficient-band-computing unit for computing an insufficient band portion required by each of the terminal apparatuses; an in-buffer-information-amount-proportional-band-allocating unit for allocating a band portion corresponding to the in-buffer-information amount to each of the terminal apparatuses and a past-use-band-allocating unit for allocating a past-use band part to each of the terminal apparatuses as a past-use band portion based on a first past-use band variable of the terminal apparatus.