Multi-layered Model for Survivability Analysis of Network Services

• US 20090157371A1
• Filed: 12/12/2007
• Published: 06/18/2009
• Est. Priority Date: 12/12/2007
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Services Organization Incorporated (Verizon Communications Inc.)
• Inventors: Conway, Adrian E.
• Granted Patent: US 8,099,272 B2
• Time in Patent Office: Days
• US Class Current: 703/13
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/06 Management of faults, events, alarms or notifications
• CPC Class Codes: H04L 41/145 involving simulating, designing, planning or modelling of a network
• CPC Class Codes: H04L 41/5012 determining service availability, e.g. which services are available at a certain point in time

Abstract

A system and method of using a multi-layered network model for analyzing the survivability of network services. The model is defined in terms of layers, connections, entities, physical processing elements, physical network elements, and physical infrastructure elements. Network services are modeled by sets of communicating entities at the application layer that are connected by connections at the underlying layers. The generality of the model constructs enable the construction of models of complex networks and services that can involve multiple layers of communication protocols, network elements, processing elements, and failover/backup mechanisms. The service survivability of a network is analyzed by projecting the failure of a set of physical elements onto the model and then determining the proportion of service affected at the application layer.

Claims

1. A method comprising:

receiving a multi-layered network model of a data communications network comprising network elements and network services;

receiving at least one set of one or more network elements to determine the effect of the failure of each set of one or more network elements;

simulating the data communications network and failures of each set of one or more network elements;

quantifying service survivability metrics of the effects on network services caused by the failure of each set of one or more network elements; and

outputting data representing the quantified service survivability metrics of the data communications network.

2. The method of claim 1, wherein simulating the data communications network and failures of each set of one or more network elements further comprises simulating failures of combinations of network elements for each set of one or more network elements and quantifying service survivability metrics of the effects on network services caused by each combination of the failed network elements.

3. The method of claim 2, further comprising determining combinations of network element failures that lead to a predetermined number of worst instances of service survivability.

4. The method of claim 1, wherein the multi-layered network model comprises at least a higher layer application layer and a lower layer physical layer.

5. The method of claim 4, wherein the network services are modeled by sets of communicating entities at the application layer, wherein the communicating entities are communicatively coupled by connections at an underlying layer.

6. The method of claim 5, wherein a connection failure at an underlying layer results in a failure at each layer higher than the underlying layer

7. The method of claim 4, wherein the quantifying service survivability metrics of effects on network services caused by the failure of each set of one or more network elements is based at least in part on the extent of service interruptions at the application layer.

8. The method of claim 1, wherein quantified service survivability metric is one or more of an average service survivability, minimum service survivability, maximum service survivability, median service survivability, or distribution of service survivability.

9. The method of claim 8, wherein the quantified service survivability metrics correspond to failures of multiple network elements occurring approximately simultaneously.

10. The method of claim 1, wherein the simulation of failed network elements comprises data indicating whether each network element in the model is operational or non-operational.

11. The method of claim 4, wherein a connection above the physical layer comprises a connection between at least two entities in that layer, and a connection with the layer below.

12. The method of claim 2, wherein every possible combination of failed network elements of a data communications network are simulated and quantified in an iterative fashion.

13. The method of claim 1, wherein network elements comprise physical and logical elements operating at any layer in the multi-layered model.

14. A computer readable medium storing an executable program comprising instructions to perform the method of claim 1.

15. A system comprising:

a network modeling module configured to provide a multi-layered network model of a data communications network that represents at least network elements and network services of the data communications network;

a failure simulation module configured to simulate a failure of one or more sets of one or more network elements in the multi-layered network model;

a survivability module configured to determining survivability data including the effect on network services caused by the failure of each set of one or more network elements; and

a display module configured to output survivability data.

16. The system of claim 15, wherein the survivability module is further configured to determine quantifiable service survivability metrics of the data communications network by analyzing the effects of failures of each set of one or more network elements of the data communications network.

17. The method of claim 16, wherein the survivability module is further configured to determine combinations of network element failures that lead to a predetermined number of worst instances of service survivability.

18. The system of claim 16, wherein the survivability module is further configured to determine quantifiable service survivability metrics of the data communications network by analyzing the effects of failures of different combinations of network elements of the data communications network.

19. The system of claim 18, wherein the survivability module is further configured to determine quantifiable service survivability metrics of the data communications network by analyzing the effects of failures for every possible combination of failed network elements of the data communications network in an iterative fashion.

20. The system of claim 16, wherein the quantifiable service survivability metric is one or more of an average service survivability, minimum service survivability, maximum service survivability, median service survivability, or distribution of service survivability.