United States Patent [19] [11] Patent Number: 4,727,537
Nichols [45] Date of Patent: Feb. 23, 1988
band Medium Specifications, Type 1BASE5: StarLAN":, IEEE Computer Society, Draft C, Oct. 1985. Pending Application, Case A. D. Franklin 3, filed 9/11/85, AT&T-IS, Serial Number 774,750, "Flow Control Scheme for a Switching Network".
Primary Examiner—Douglas W. Olms
Assistant Examiner—Melvin Marcelo
Attorney, Agent, or Firm—Donald M. Duft; James M.
Graziano; John C. Moran
[57] ABSTRACT
A data transmission flow control arrangement for controlling the flow of data packets to a network as tramsmitted by one or more data transmitting and receiving devices via an interface is disclosed. The disclosed flow control arrangement provides circuitry in the interface responsive to the storage capacity of a buffer included in the interface. If the buffer contains sufficient space to store a data packet of maximum length, data transmissions continue unencumbered. However, if the buffer contains insufficient space to accomodate a data packet of maximum length, the specialized circuitry of the interface responds to this condition and applies a signal to all of the associated transmitting and receiving devices of the interface. The jamming signal simulates the conditions associated with a busy network and therefore, inhibits the transmission of data from any of the associated transmitting and receiving devices. The specialized circuitry of the interface terminates the application of the jamming signal to all associated transmitting and receiving devices when the buffer again contains sufficient space to accommodate a data packet of maximum length.
10 Claims, 6 Drawing Figures
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