公开(公告)号：DE68923055D1

公开(公告)日：1995-07-20

申请号：DE68923055

申请日：1989-07-08

Applicant: IBM

Inventor： BRANTLEY WILLIAM CAIN ,  GROH WAYNE STEPHEN ,  JACKSON RORY DANA ,  NORTON VERN ALAN

IPC: H04L13/08 ,  H04L12/56 ,  H04L29/06

Abstract: Packet switch protocol and circuitry for implementing it are disclosed. According to this protocol, a message transmitter of a first node in the network may send data through a data transmission link at a predetermined rate until it is signalled, via a control signal generated by a message receiver in a second node, to suspend its transmissions. The message transmitter may also be signalled to resume transmitting data. The message receiver includes a buffer memory in which messages are temporarily stored if their selected path is blocked as they pass through the network. When the amount of available space in the buffer is less than a preprogrammed threshold value, the message receiver generates the control signal to suspend message transmission. This threshold value leaves sufficient space in the buffer to store any data which may be in the pipeline between the transmitter and the receiver. When the amount of available space rises above this threshold, the message receiver indicates to the transmitter to resume transmission. A message spanning an interface during transmission may be suspended without losing spatial contiguousness. The message transmitter also transmits a signal which marks the last portion of a message. This signal is stored in the buffer with the message data and is used to delimit messages in the buffer, allowing multiple messages to be stored in one buffer without extra delimiting values.

公开(公告)号：DE2723523A1

公开(公告)日：1978-01-05

申请号：DE2723523

申请日：1977-05-25

Applicant: IBM

Inventor： JACKSON RORY DANA ,  RACKL WILLI KARL

IPC: G06F5/00 ,  G06F3/14 ,  G06F12/04 ,  G09G1/02 ,  G09G5/42 ,  H03M7/46 ,  G11D1/00 ,  G11C9/00 ,  G11B5/02 ,  G06F5/06

Abstract: When a data stream includes long sections of data that are repeated periodically, storage space may be saved by not including full repetitions of such sections in the storage. However, when the data is to be read from storage for utilization, the omitted repetitious sections must be inserted. This is accomplished by providing hardware apparatus which recognizes a particular flag occurring in the stored data. After recognizing the flag, the expansion apparatus interprets the next piece of information in the data stream as being the storage address of the start of a section of data that is to be inserted into the data stream; the next piece of information is interpreted as being the length of the section of data to be inserted; and the next following piece of information is the number of times that the section of data is to be inserted. The apparatus will respond to the flag and its associated indicators by inserting the appropriate data section the indicated number of times.

公开(公告)号：DE68923055T2

公开(公告)日：1995-12-21

申请号：DE68923055

申请日：1989-07-08

Applicant: IBM

Inventor： BRANTLEY WILLIAM CAIN ,  GROH WAYNE STEPHEN ,  JACKSON RORY DANA ,  NORTON VERN ALAN

IPC: H04L13/08 ,  H04L12/56 ,  H04L29/06

Abstract: Packet switch protocol and circuitry for implementing it are disclosed. According to this protocol, a message transmitter of a first node in the network may send data through a data transmission link at a predetermined rate until it is signalled, via a control signal generated by a message receiver in a second node, to suspend its transmissions. The message transmitter may also be signalled to resume transmitting data. The message receiver includes a buffer memory in which messages are temporarily stored if their selected path is blocked as they pass through the network. When the amount of available space in the buffer is less than a preprogrammed threshold value, the message receiver generates the control signal to suspend message transmission. This threshold value leaves sufficient space in the buffer to store any data which may be in the pipeline between the transmitter and the receiver. When the amount of available space rises above this threshold, the message receiver indicates to the transmitter to resume transmission. A message spanning an interface during transmission may be suspended without losing spatial contiguousness. The message transmitter also transmits a signal which marks the last portion of a message. This signal is stored in the buffer with the message data and is used to delimit messages in the buffer, allowing multiple messages to be stored in one buffer without extra delimiting values.