Methods and devices for prioritizing in handling buffers in packet networks

Claim 1

A method for handling in a packet network a buffer, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to give different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the method comprising, for each arrived packet, the following steps: a) determining the loss priority class of the packet, b) determining whether the present total number of packets stored in the buffer is smaller than a threshold value associated with the loss priority class of the packet, c) if the determination in b) gives the answer yes, storing the packet in the buffer and otherwise discarding the packet, for each arrived packet also determining the delay priority class of the packet and in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class.

Claim 2

A method for handling in a packet network a buffer, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to give different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the method comprising, for each arrived packet, the following steps: a) determining the loss priority class of the packet, b) determining whether the present total number of packets stored in the buffer is smaller than a threshold value associated with the loss priority class of the packet, c) if the determination in b) gives the answer yes, storing the packet in the buffer and otherwise discarding the packet, for each arrived packet also determining the delay priority class of the packet and in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class.

Claim 3

A method for handling in a packet network a buffer, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to give different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the method comprising, for each arrived packet, the following steps: a) determining the loss priority class of the packet, b) determining whether the present total number of packets stored in the buffer is smaller than a threshold value associated with the loss priority class of the packet, c) if the determination in b) gives the answer yes, storing the packet in the buffer and otherwise discarding the packet, for each arrived packet also determining the delay priority class of the packet and in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein with each lower delay priority class time intervals having predetermined lengths are associated, such that a packet from a lower delay priority class is chosen instead of a packet from a higher delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available.

Claim 4

A method for handling in a packet network a buffer, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to give different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the method comprising, for each arrived packet, the following steps: a) determining the loss priority class of the packet, b) determining whether the present total number of packets stored in the buffer is smaller than a threshold value associated with the loss priority class of the packet, c) if the determination in b) gives the answer yes, storing the packet in the buffer and otherwise discarding the packet, for each arrived packet also determining the delay priority class of the packet and in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein with each lower delay priority class time intervals having predetermined lengths are associated, such that a packet from a lower delay priority class is chosen instead of a packet from a higher delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available.

Claim 5

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and a threshold value being associated with each loss priority class, each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to allow different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the device comprising an input on which the arrived packets arrive, the buffer memory, an output on which arrived packets are forwarded, a logic unit for determining those packets to be stored in the buffer memory comprising a) means for determining the loss priority class of an arrived packet, b) means for determining if the present total number of packets stored in the buffer memory is less than the threshold value associated with the loss priority class of the arrived packet and for forwarding, when this condition is satisfied, a signal thereof to c) means for storing the arrived packet in the buffer memory, and d) means for determining for each arrived packet the delay priority class of the arrived packet and another logic unit for determining which packet is to be sent from the buffer memory comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class and for transferring the selected packets to the output for forwarding.

Claim 6

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and a threshold value being associated with each loss priority class, each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to allow different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the device comprising an input on which the arrived packets arrive, the buffer memory, an output on which arrived packets are forwarded, a logic unit for determining those packets to be stored in the buffer memory comprising a) means for determining the loss priority class of an arrived packet, b) means for determining if the present total number of packets stored in the buffer memory is less than the threshold value associated with the loss priority class of the arrived packet and for forwarding, when this condition is satisfied, a signal thereof to c) means for storing the arrived packet in the buffer memory, and d) means for determining for each arrived packet the delay priority class of the arrived packet and another logic unit for determining which packet is to be sent from the buffer memory comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class and for transferring the selected packets to the output for forwarding.

Claim 7

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and a threshold value being associated with each loss priority class, each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to allow different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the device comprising an input on which the packets arrive, the buffer memory, an output on which the packets are forwarded, a logic unit for determining those packets to be stored in the buffer memory comprising a) means for determining the loss priority class of an arrived packet, b) means for determining if the present total number of packets stored in the buffer memory is less than the threshold value associated with the loss priority class of the arrived packet and for forwarding, in the case that this condition is satisfied, a signal thereof to c) means for storing the arrived packet in the buffer memory, and d) means for determining for each arrived packet also the delay priority class of the packet and another logic unit for determining which packet is to be sent from the buffer memory comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein each lower delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class if no packet from the lower delay priority class has been forwarded during the time interval with the predetermined length associated with the delay priority class thereof and if such a packet is available, and means for transferring a chosen packet to the output for forwarding.

Claim 8

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, in particular in a switch device, each packet belonging to a certain loss priority class of at least two loss priority classes and a threshold value being associated with each loss priority class, each packet also belonging to a certain delay priority class of at least two delay priority classes, the delay priority classes being intended to allow different delays for the packets belonging to said classes, such that longer delays are allowed for packets belonging to delay priority classes having a lower delay priority, the device comprising an input on which the packets arrive, the buffer memory, an output on which the packets are forwarded, a logic unit for determining those packets to be stored in the buffer memory comprising a) means for determining the loss priority class of an arrived packet, b) means for determining if the present total number of packets stored in the buffer memory is less than the threshold value associated with the loss priority class of the arrived packet and for forwarding, in the case that this condition is satisfied, a signal thereof to c) means for storing the arrived packet in the buffer memory, and d) means for determining for each arrived packet also the delay priority class of the packet and another logic unit for determining which packet is to be sent from the buffer memory comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein each lower delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class if no packet from the lower delay priority class has been forwarded during the time interval with the predetermined length associated with the delay priority class thereof and if such a packet is available, and means for transferring a chosen packet to the output for forwarding.

Claim 9

A method for handling in a packet network a buffer, in which arrived data packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising the step of, in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower priority class wherein each lower delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available.

Claim 10

A method for handling in a packet network a buffer, in which arrived data packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising the step of, in forwarding packets from the buffer, choosing packets belonging to a higher delay priority class before packets belonging to a lower priority class wherein each lower delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available.

Claim 11

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising an output on which the packets arrive, the buffer memory, an output on which the packets are forwarded from the buffer memory, a logic unit for determining which packet is in turn to be forwarded from the buffer memory, comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein each low delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available, and means for transferring the chosen data packet to the output for forwarding.

Claim 12

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising an output on which the packets arrive, the buffer memory, an output on which the packets are forwarded from the buffer memory, a logic unit for determining which packet is in turn to be forwarded from the buffer memory, comprising means for choosing packets belonging to a higher delay priority class before packets belonging to a lower delay priority class wherein each low delay priority class is associated with time intervals having predetermined lengths, such that instead of a packet from a higher delay priority class a packet is chosen from a lower delay priority class, if no packet from the lower delay priority class has been sent during the time interval having the predetermined length associated with the delay priority class thereof and if such a packet is available, and means for transferring the chosen data packet to the output for forwarding.

Claim 16

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising an output on which the packets arrive, the buffer memory, an output on which the packets are forwarded from the buffer, a logic unit for determining which packet is in turn to be forwarded from the buffer memory, comprising means for selecting packets belonging to a higher delay priority class before packets belonging to a lower delay priority class based on lists stored in a memory for each delay priority class, each list accommodating addresses to the data packets, which belong to this delay priority class and which are stored in the buffer memory, and means for transferring a chosen data packet to the output for forwarding.

Claim 17

A device for handling in a packet network a buffer memory, in which arrived packets are stored before they are forwarded, each packet belonging to a respective one of at least two delay priority classes, comprising an output on which the packets arrive, the buffer memory, an output on which the packets are forwarded from the buffer, a logic unit for determining which packet is in turn to be forwarded from the buffer memory, comprising means for selecting packets belonging to a higher delay priority class before packets belonging to a lower delay priority class based on lists stored in a memory for each delay priority class, each list accommodating addresses to the data packets, which belong to this delay priority class and which are stored in the buffer memory, and means for transferring a chosen data packet to the output for forwarding.