System and method for pre-filtering low priority packets at network nodes in a network service class utilizing a priority-based quality of service

• US 6,868,061 B1
• Filed: 12/10/1998
• Issued: 03/15/2005
• Est. Priority Date: 12/10/1998
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Kilkki, Matti Kalevi, Ruutu, Jussi Pekka Olavi
• Primary Examiner(s): Nguyen, Chau
• Assistant Examiner(s): DUONG, DUC T
• Application Number:
  US09/209,183
• Time in Patent Office: 2,287 Days
• Field of Search: 370/230, 370/231, 370/232, 370/233, 370/234, 370/235, 370/252, 370/395.21, 370/395.42, 370/395.43, 370/400, 370/401
• US Class Current: 370/230.1
• CPC Class Codes: H04L 2012/5615 Network termination, e.g. NT1, NT2, PBX
• CPC Class Codes: H04L 2012/5636 Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• CPC Class Codes: H04L 2012/5647 Cell loss
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 49/3081 ATM peripheral units, e.g. policing, insertion or extraction
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

A system and method for reducing network node congestion by filtering out comparatively low priority packets prior to execution of other node functions, such as routing and switching, in packet-based network transmissions. The volume of packets is reduced by intercepting the information packets prior to their input to the network node. A portion of the intercepted packets are filtered out based on parameters corresponding to a probable packet acceptability at the network node. The remaining portion of the intercepted packets are forwarded to the network node for processing by the network packet functions.

Claims

1. A method for use in a network having at least one network node capable of routing information packets between one or more node inputs and one or more node outputs, for reducing the volume of packets requiring processing by network packet functions of the network node, the method comprising:

intercepting the packets prior to their input to the network node;

filtering out a portion of the intercepted packets based on parameters corresponding to a probable packet acceptability at the network node; and

forwarding a remaining portion of the intercepted packets to the network node for processing by the network packet functions, wherein filtering out the portion of the intercepted packets comprises;

receiving a feedback of the parameters from the network node; and

adjusting an output rate into the corresponding input of the network node based on the parameters.

2. The method of claim 1, wherein receiving the feedback of the parameters comprises dynamically modifying the parameters at the network node based on a load condition of the network node.

3. A method for use in a network having at least one network node capable of routing information packets between one or more node inputs and one or more node outputs, for reducing the volume of packets requiring processing by network packet functions of the network node, the method comprising:

establishing parameters indicative of a desired packet traffic flow;

intercepting the packets destined for a particular one of the inputs of the network node prior to their input to the particular input;

comparing attributes of the intercepted packets with the established parameters to determine whether the attributes conform to the established parameters;

discarding the intercepted packets whose attributes do not conform to the established parameters;

forwarding the intercepted packets, whose attributes conform to the established parameters, to the particular input to which the intercepted packet was destined;

generating the parameters at the network node based on a node congestion level; and

providing feedback of the generated parameters for comparison to the attributes of the intercepted packets.

4. A packet pre-filtering device, for use in a network having at least one network node capable of routing information packets between one or more network node inputs and one or more network node outputs, comprising:

a packet filter input to intercept the packets destined for a particular one of the network node inputs, wherein the packets include a packet priority value;

a control input to receive parameters corresponding to a packet acceptance threshold;

a comparator coupled to receive and compare the packet acceptance threshold and the packet priority values from the intercepted packets;

a packet filter output to forward the intercepted packets having a packet priority value within the packet acceptance threshold to the particular one of the network node inputs to which the intercepted packet was destined; and

at least one packet buffer to receive the intercepted packets and to generate the packet acceptance threshold based on an occupancy level of the at least one packet buffer, wherein the at least one packet buffer comprises;

a real-time packet buffer to receive and buffer real-time packets; and

a non-real-time packet buffer to receive and buffer non-real-time packets.

5. The packet pre-filtering device as in claim 4, further comprising:

a comparator to compare a real-time designator in each of the intercepted packets to a predetermined real-time indicator;

a packet router to route each of the intercepted packets to one of the real-time packet buffer and the-non-real-time packet buffer based on the result of the comparison of the real-time designator and the predetermined real-time indicator;

a processing unit coupled to receive an indication of the occupancy level of each of the real-time and non-real-time packet buffers, and to generate the packet acceptance threshold in response thereto.

6. The packet pre-filtering device as in claim 4, wherein:

each of the network nodes comprises a packet routing and switching unit to selectively route the intercepted packets to one or more of the network node outputs and to provide an indication of the overall load at the network node; and

the control input is coupled to the routing and switching unit to receive the packet acceptance threshold via a feedback signal of the indication of the overall load at the network node.

7. The packet pre-filtering device as in claim 6, further comprising at least one packet buffer to receive the intercepted packets, wherein the packet buffer includes a variable rate packet output controlled by the overall load indication at the control input.

8. A method for use in a network having at least one network node capable of routing information packets between one or more node inputs and one or more node outputs, for reducing the volume of packets requiring processing by network packet functions of the network node, the method comprising:

intercepting the packets prior to their input to the network node;

filtering out a portion of the intercepted packets based on parameters corresponding to a probable packet acceptability at the network node; and

forwarding a remaining portion of the intercepted packets to the network node for processing by the network packet functions, wherein filtering out the portion of the intercepted packets comprises;

receiving a feedback of the parameters from the network node; and

adjusting a packet discard rate based on the parameter.