INVESTIGATING QUALITY OF SERVICE DISRUPTIONS IN MULTICAST FORWARDING TREES

• US 20110255421A1
• Filed: 04/17/2010
• Published: 10/20/2011
• Est. Priority Date: 01/28/2010
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Sanjay, Kumar, Shrirang, Hegde, Manoj, Kumar Jain
• Granted Patent: US 8,958,310 B2
• Time in Patent Office: Days
• US Class Current: 370/244
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 43/0894 Packet rate

Abstract

Methods, computer-readable storage media and systems may be provided for investigating a Quality of Service (“QoS”) disruption among nodes of a computer network that form a multicast forwarding tree. A topology of the multicast forwarding tree may be identified. Performance data may be collected at interfaces between nodes of the multicast forwarding tree. A source of the QoS disruption may be identified by mapping the performance data to the topology.

Claims

1. A method of investigating a Quality of Service (“

QoS”

) disruption among nodes of a computer network forming a multicast forwarding tree, comprising;

identifying a topology of the multicast forwarding tree;

collecting performance data at interfaces of nodes which are part of the multicast forwarding tree; and

mapping the performance data to the topology.

2. The method of claim 1, wherein identifying the topology includes:

discovering multicast forwarding and routing information directing a multicast flow; and

computing the topology of nodes which are receiving the multicast flow using reverse path forwarding.

3. The method of claim 2, further comprising collecting performance data at ingress interfaces on nodes which are receiving the multicast flow.

4. The method of claim 3, further comprising associating the performance data collected at an ingress interface at each node with an egress interface of a parent node.

5. The method of claim 4, further comprising identifying a first node of the topology as a source of the QoS disruption where the first node has an egress data packet flow rate that is less than an ingress data packet flow rate of the first node.

6. The method of claim 5, further comprising calculating a percentage of data packets dropped by the first node by dividing the egress data packet flow rate of the first node by the ingress data packet flow rate of the first node.

7. The method of claim 1, further comprising rendering the forwarding tree topology and the mapped performance data in a human-readable format.

8. A computer-readable storage medium having computer-executable instructions for investigating a QoS disruption among nodes of a multicast forwarding tree, the instructions causing a computer to perform steps comprising:

discovering multicast forwarding and routing information directing a multicast flow;

computing a topology of nodes which are receiving the multicast flow using reverse path forwarding;

collecting performance data at interfaces between nodes of the computed topology; and

mapping the performance data to the topology.

9. The computer-readable storage medium of claim 8, further including computer-executable instructions for storing the discovered multicast forwarding and routing information in an n-ary tree data structure.

10. The computer-readable storage medium of claim 8, further including computer-executable instructions for collecting performance data only at ingress interfaces on nodes which are receiving the multicast flow.

11. The computer-readable storage medium of claim 10, further including computer-executable instructions for associating the performance data collected at an ingress interface of each node with an egress interface of a parent node.

12. The computer-readable storage medium of claim 11, further including computer-executable instructions for identifying a first node of the topology as a source of the QoS disruption where the first node has an egress data packet flow rate that is less than an ingress data packet flow rate of the first node.

13. The computer-readable storage medium of claim 12, further including computer-executable instructions for calculating a percentage of data packets dropped by the first node by dividing the egress data packet flow rate of the first node by the ingress data packet flow rate of the first node.

14. The computer-readable storage medium of claim 8, wherein discovering multicast forwarding and routing information is performed using SNMP.

15. A system for investigating a QoS disruption among nodes of a multicast forwarding tree, the system comprising:

a discovery component configured to obtain multicast forwarding and routing information directing a multicast flow;

a polling component configured to collect performance data at interfaces of nodes which are receiving the multicast flow; and

a forwarding tree computation component configured to compute forwarding tree topology of the nodes which are receiving the multicast flow and map the performance data on the tree topology.

16. The system of claim 15, wherein the polling component is configured to collect performance data at ingress interfaces of nodes which are receiving the multicast flow.

17. The system of claim 16, wherein the forwarding tree computation component is configured to associate performance data collected at an ingress interface of each node with an egress interface of a parent node.

18. The system of claim 17, wherein the forwarding tree computation component is configured to compute forwarding tree topology of the nodes which are receiving the multicast flow using reverse path forwarding.

19. The system of claim 15, wherein the discovery component is configured to obtain the multicast forwarding and routing information using SNMP.

20. The system of claim 15, wherein the polling component is configured to collect the performance data upon receiving notification from the discovery component.