Packet switch and packet switching method using priority control based on congestion status within packet switch
AssigneeKabushiki Kaisha Toshiba
InventorsYoshimitsu Shimojo, Hideaki Nakakita
Life of this patent
Estimating the term…
Abstract
A packet switch and a packet switching method capable of taking the full advantage of the transfer capability of the packet switch by avoiding the influence due to the congestion are disclosed. In the packet switch, the priority level according to the congestion status of the transfer target is attached to a packet, and the processing at a time of packet collision is carried out by accounting for this priority level, so that it becomes possible to carry out the packet transfer control according to the congestion status of the transfer target of each packet.
Claims18
A packet switch, comprising:
- a plurality of input side transfer units from which packets are entered;
- a plurality of output side transfer units from which packets are outputted;
- a switching unit through which each packet entered from each input side transfer unit is switched to a desired output side transfer unit;
- a congestion status monitoring unit configured to monitor a congestion status of each transfer target to which each packet can be destined to reach within the packet switch;
- a priority level attaching unit configured to attach a priority level to each packet, according to the congestion status of a transfer target of each packet monitored by the congestion status monitoring unit;
- and
- a packet selection unit configured to select one packet that is to be transferred at a higher priority among colliding packets when a packet collision occurs within the switching unit, according to the priority level attached to each colliding packet.
A packet switch, comprising:
- a plurality of input side transfer units from which packets are entered;
- a plurality of output side transfer units from which packets are outputted;
- a switching unit through which each packet entered from each input side transfer unit is switched to a desired output side transfer unit, the switching unit having a configuration in which no packet collision occurs;
- a congestion status monitoring unit configured to monitor a congestion status of each transfer target to which each packet can be destined to reach within the packet switch;
- and
- a connection pattern calculation engine configured to attach a priority level to each packet, according to the congestion status of a transfer target of each packet monitored by the congestion status monitoring unit, carry out a simulation in which each packet is assumed to be transferred through a virtual switching network having a topology in which a packet collision may occur and a packet to be transferred at higher priority among colliding packets is selected according to the priority level attached to each colliding packet when the packet collision occurs in the virtual switching network, and determine a connection pattern of the switching unit such that a result of switching packets at the switching unit coincides with a result of transferring packets from the input side transfer units to the output side transfer units according to the simulation.
A packet switching method of a packet switch in which a packet is transferred from an input side transfer unit via a switching unit to a desired output side transfer unit, the method comprising:
- transferring the packet by attaching a priority level according to a congestion status of a transfer target of the packet to which the packet is destined to reach within the packet switch, from the input side transfer unit to the switching unit;
- switching the packet transferred from the input side transfer unit according to the transfer target of the packet at the switching unit, and transferring one colliding packet selected from colliding packets by accounting for the priority level attached to each colliding packet, at higher priority to the output side transfer unit when a packet collision occurs within the switching unit;
- and
- notifying information indicating a monitoring result of the congestion status for a prescribed unit of monitoring, from the output side transfer unit to which the packet has reached, to the input side transfer unit which transmitted the packet.
A computer program product for causing one or a plurality of a computers to function as a packet switch in which a packet is transferred from an input side transfer unit via a switching unit to a desired output side transfer unit, the switching unit having a function of selecting one packet that is to be transferred at a higher priority among colliding packets when a packet collision occurs within the switching unit, according to a priority level attached to each colliding packet, the computer program product comprising:
- a first computer readable program code for causing said one or a plurality of computers to monitor a congestion status of each transfer target to which each packet can be destined to reach within the packet switch;
- and
- a second computer readable program code for causing said one or a plurality of computers to attach the priority level to each packet, according to the congestion status of a transfer target of each packet monitored by the first computer readable program code.
Dependencies are inferred from the claim text.