Method and apparatus for automatically configuring a network device to support a virtual network

Claims

What is claimed is:

1. A physical networking system including a plurality of end-stations said physical networking system comprising:

a. at least one switching device adapted to support a virtual network;

b. at least one end-station interconnected with said at least one switching device, wherein said at least one switching device and said end-station are interconnected in a first topology; and

c. a configuration device, said configuration device including:

i. a configuration modification detection circuit to detect the modification of said first topology;

ii. a configuration policy maintenance circuit to store a policy defining said virtual network as including a logical sub-group of said plurality of end stations according to a predetermined logical criteria

iii. a policy evaluation circuit to determine a manner in which to reconfigure said at least one switching device to implement said virtual network upon said detection of said modification of said first topology, said manner being determined in accordance with said policy; and

iv. a reconfiguration circuit automatically to reconfigure said at least one switching device in said manner.

2. The networking system of claim 1 wherein said reconfiguration includes coupling said at least one end-station in said networking system to form said virtual network according to said policy.

3. The networking system of claim 1 wherein said reconfiguring includes determining an efficient manner in which to reconfigure said at least one switching device to form said virtual network.

4. The networking system of claim 1 wherein said reconfiguring further includes reconfiguring said at least one switching device to remove said virtual network when said virtual network is no longer required.

5. The networking system of claim 1 wherein said reconfiguring further includes reconfiguring said at least one switching device to interconnect said at least one end-station and said at least one switching device so as to include said at least one end-station to said virtual network.

6. The networking system of claim 1 wherein said configuration modification detection circuit comprises a polling circuit to poll at least one automatic topology determination circuit to detect said modification of said first topology.

7. The networking system of claim 1 wherein said configuration modification detection circuit comprises a trap reception circuit to receive traps generated by at least one automatic topology determination circuit upon said modification of said first topology.

8. The networking system of claim 1 wherein said configuration modification detection circuit comprises a polling circuit to poll said at least one switching device to detect said modification of said first topology.

9. The networking system of claim 1 wherein said configuration modification detection circuit comprises a trap reception circuit to receive traps generated by said at least one switching device upon said modification of said first topology.

10. The networking system of claim 1 wherein said policy includes a member policy table identifying said at least one end-station as forming part of said virtual network.

11. The networking system of claim 1 wherein said policy includes an override policy table specifying that said at least one switching device should not be reconfigured upon said modification of said first topology.

12. The networking system of claim 1 wherein said policy includes an automatic policy table specifying automatic configuration of said at least one switching device to implement said virtual network, wherein said virtual network is characterized by a predetermined attribute of said at least one end-station.

13. The networking system of claim 1 wherein said policy identifies hardware addresses to be coupled to form said virtual network.

14. The networking system of claim 1 wherein said policy identifies ports on said at least one switching device which form said virtual network.

15. The networking system of claim 1 wherein said policy identifies asynchronous transfer mode (ATM) addresses to be coupled to form said virtual network.

16. The networking system of claim 1 wherein said policy identifies network layer addresses to be coupled to form said virtual network.

17. The networking system of claim 16 wherein said network layer addresses include internet protocol (IP) addresses.

18. The networking system of claim 1 wherein said policy specifies multiple instances of specified attributes to be coupled to form said virtual network.

19. An automatic method in a configuration device in a physical networking system having at least one switching device adapted to implement a virtual network within said physical networking system, and at least one end-station interconnected with said at least one switching device, wherein said at least one switching device and said at least one end-station are interconnected in a first topology, and said virtual network comprises a logical grouping of end-stations within said physical networking system, said automatic method comprising the steps of:

a. storing a policy defining said virtual network upon modification of said first topology, according to a predetermined logical criteria, as including said logical grouping of end-stations within said physical networking system;

b. detecting said modification of said first topology;

c. determining a manner in which to reconfigure said at least one switching device to implement said virtual network upon said detection of said modification of said first topology, said manner being determined in accordance with said policy; and

d. automatically reconfiguring said at least one switching device in said manner.

20. A method for managing a virtual network in a switched, physical networking system comprising at least one end-station, a switching device and a configuration device, wherein said virtual network comprises a logical, sub-grouping of end-stations within said physical network defined according to a predetermined logical criteria, said method of managing said virtual network comprising the following steps:

a. said configuration device communicating with said switching device to determine changes of connectivity of at least one end-station and said switching device in said switched networking system;

b. said configuration device referencing a policy for management of said virtual network in said switched networking system in order to determine reconfiguration of said switching device for said management of said virtual network;

c. said configuration device determining said reconfiguration of said switching device; and

d. said configuration device automatically performing said reconfiguration of said switching device for said management of said virtual network.

21. The method of claim 20 wherein said managing includes creating said virtual network.

22. The method of claim 20 wherein said managing includes deleting said virtual network.

23. The method of claim 20 wherein said managing includes maintaining said virtual network.

24. The method of claim 20 wherein said managing includes creating, deleting and maintaining said virtual network.

25. The method of claim 20 wherein said managing includes creating, deleting and maintaining said virtual network in order to create an efficient communication path among said virtual network and another virtual network.

26. Network management apparatus for use in a physical networking system, said physical networking system having at least one switching device capable of implementing a virtual network and at least one end-station interconnectable with said switching device, wherein said at least one switching device and said at least one end-station are interconnected in a first topology, and wherein said virtual network comprises a sub-group of end-stations of said physical networking system allocated to a virtual network grouping according to a predetermined logical criteria, said network management apparatus comprising:

a. a configuration modification detection circuit to detect the modification of said first topology;

b. a policy evaluation circuit to identify said at least one end-station as being allocated to said virtual network grouping utilizing a policy upon said detection of said modification of said first topology; and

c. a reconfiguration circuit automatically to reconfigure said switching device to implement said virtual network grouping of said at least one end-station.

27. The apparatus of claim 26 further comprising a configuration policy maintenance circuit to store said policy for determining said virtual network grouping of said at least one end-station.

28. The apparatus of claim 26 wherein said configuration modification detection circuit comprises a polling circuit to poll at least one automatic topology determination circuit in said networking system to detect said modification of said first topology.

29. The apparatus of claim 26 wherein said configuration modification detection circuit comprises a trap reception to receive traps generated by at least one automatic topology determination circuit in said networking system upon said modification of said first topology.

30. The apparatus of claim 26 wherein said configuration modification detection circuit comprises a polling circuit to poll said at least one switching device in said networking system to detect said modification of said first topology.

31. The apparatus of claim 26 wherein said configuration modification detection circuit comprises a trap reception circuit to receive traps generated by said switching device in said networking system upon said modification of said first topology.

32. The apparatus of claim 31 wherein said configuration modification detection circuit generates a list of end-stations requiring evaluation.

33. The apparatus of claim 32 wherein said policy evaluation circuit matches said list of end-stations requiring evaluation with said policy in order to determine said virtual network grouping.

34. The apparatus of claim 33 wherein said reconfiguration circuit determines said reconfiguring of said at least one switching device according to said virtual network grouping of said at least one end-station.

35. The apparatus of claim 26 wherein said policy includes a member policy table identifying said at least one end-station as forming part of said virtual network.

36. The apparatus of claim 26 wherein said policy includes an override policy table specifying that said at least one switching device should not be reconfigured upon said modification of said first topology.

37. The apparatus of claim 26 wherein said policy includes an automatic policy table specifying automatic creation of said virtual network based on a predetermined attribute of said at least one end-station.

38. The apparatus of claim 26 wherein said policy identifies hardware addresses to be coupled to form said virtual network.

39. The apparatus of claim 26 wherein said policy identifies ports on said at least one switching device which form said virtual network.

40. The apparatus of claim 26 wherein said policy identifies asynchronous transfer mode (ATM) addresses to be coupled to form said virtual network.

41. The apparatus of claim 26 wherein said policy identifies network layer addresses to be coupled to form said virtual network.

42. The apparatus of claim 41 wherein said network layer addresses include internet protocol (IP) addresses.

43. The apparatus of claim 26 wherein said policy includes a specification of multiple instances of specified attributes to be coupled to form said virtual network.

44. Network management apparatus in a networking system including a plurality of end-stations, said networking system having at least one switching device capable of supporting a virtual network and at least one end-station interconnected with said at least one switching device, wherein said at least one switching device and said at least one end-station are interconnected in a first topology, and wherein said virtual network comprises a logical sub-grouping of end stations defined according to a predetermined logical criteria, said network management apparatus comprising:

a. a configuration policy maintenance circuit for storing a policy defining said virtual network and allocating said at least one end-station to said virtual network according to said predetermined logical criteria;

b. a configuration modification detection circuit for detecting modification of said first topology;

c. a policy evaluation circuit for determining said allocation of said at least one end-station to said virtual network, by referencing said policy stored in said configuration policy maintenance circuit, upon said detection of said modification of said first topology; and

d. a reconfiguration circuit for automatically reconfiguring said at least one switching device upon said detection of said modification of said first topology to implement said virtual network.

45. An automatic method for configuration of a networking system having at least one switching device capable of supporting a virtual network and at least one end-station interconnectable with said at least one switching device, wherein said at least one switching device and at least one end-station are interconnected in a first topology, and wherein said virtual network comprises a plurality of end-stations allocated to a logical grouping defined according to a predetermined logical criteria, said method comprising the following steps:

storing a policy defining said logical grouping of said end-stations according to said predetermined logical criteria;

detecting modification of said first topology;

upon detection of said modification, determining said logical grouping of said at least one end-station to form said virtual network according to said policy; and

upon said detection of said modification, automatically reconfiguring said at least one switching device in said network to support said logical grouping of said at least one end-station.

46. The method of claim 45 wherein said configuration modification detection comprises polling at least one topology determination circuit in said network to determine said modification of said first topology.

47. The method of claim 45 wherein said configuration modification detection comprises receiving traps generated by said at least one topology determination circuit in said network upon said modification of said first topology.

48. The method of claim 45 wherein said configuration modification detection comprises polling said at least one switching device in said network to determine said modification of said first topology.

49. The method of claim 45 wherein said configuration modification detection comprises receiving traps generated by said at least one switching device in said network upon said modification of said first topology.

50. The method of claim 49 wherein said configuration modification detection generates a list of end-stations requiring evaluation.

51. The method of claim 50 wherein said policy evaluation matches said list of end-stations requiring evaluation with said policy in order to determine said logical grouping.

52. The method of claim 51 wherein said reconfiguration circuit determines said reconfiguring of said at least one switching device according to said logical grouping of said at least one end-station.

53. The method of claim 45 wherein said policy includes a member policy table identifying said at least one end-station as forming part of said virtual network.

54. The method of claim 45 wherein said policy includes an override policy table specifying that said at least one switching device should not be reconfigured upon said modification of said first topology.

55. The method of claim 45 wherein said policy includes an automatic policy table specifying automatic creation of said virtual network based on a predetermined attribute of said at least one end-station.

56. The method of claim 45 wherein said policy identifies hardware addresses to be coupled to form said virtual network.

57. The method of claim 45 wherein said policy identifies ports on said at least one switching device which form said virtual network.

58. The method of claim 45 wherein said policy identifies asynchronous transfer mode (ATM) addresses to be coupled to form said virtual network.

59. The method of claim 45 wherein said policy identifies network layer addresses to be coupled to form said virtual network.

60. The method of claim 59 wherein said network layer addresses include internet protocol (IP) addresses.

61. The method of claim 45 wherein said policy includes a specification of multiple instances of specified attributes of said at least one end station be coupled to form said virtual network.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to networking systems. More specifically, the present invention relates to an automatic method of re-configuring hubs, switches and end-stations in a switched networking system in order to allow automatic virtual local area network (VLAN) management.

2. Background Information

Due to the proliferation of local area networks (LAN's), needs have developed for more powerful tools to manage such LAN's as they increase in complexity and size. One technique used in networking systems for managing very large networks is known as the virtual local area network (VLAN), which allows collections of end-user devices to directly communicate with one another. A VLAN is a logical network wherein the end-user devices in the network can directly communicate with one another without traversing an inter-networking device. Each of the devices in a VLAN can receive each other's multicast traffic. VLANs typically can comprise a number of logical domains overlaid on a physical network. Thus, VLANs provide the capability to provide certain networking resources to end-stations in the VLAN, even though the end-stations are widely distributed in a switched network.

Because of the size and complexity of some switched networks, especially those in which VLANs may be implemented, management of VLANs becomes an increasingly complex management task. For example, using present technology, devices in the network must be independently configured in order for widely distributed devices to operate as a single VLAN. As the number of VLANs in a switched network increases, the task of configuring and maintaining the network to retain certain end-stations as members of certain VLANs becomes an almost insurmountable process for a network manager. For example, as stations are added, moved or removed in the physical network, network devices need to be reconfigured in such a way that network services (connectivity) are provided to the end-station without disruption. Using manual prior art techniques, in networks having large numbers of nodes, this is very burdensome and time consuming.

Prior art methods of VLAN configuration primarily involve manual reconfiguration by a network manager of VLANs by the reconfiguration of the existing network hardware. Thus, as nodes are added, removed or moved, devices in the network fabric have to be manually reconfigured in order to reconfigure the network appropriately. This poses substantial scalability, time and cost problems for network managers and overall network maintenance. In addition, prior art means for reconfiguration do not address the problems associated with very large systems spanning across different technologies (e.g., those incorporating cell-switched, frame-switched and configuration switched devices).

Thus, the prior art of network configuration, especially in those implementing virtual local area networks, have several deficiencies.

SUMMARY AND OBJECTS OF THE PRESENT INVENTION

One of the objects of the present invention is to provide an improved method for configuring virtual local area networks.

Another of the objects of the present invention is to provide an automated tool for updating the network fabric in a system where devices may move, be added/removed or characteristics of the network may otherwise be changed.

Yet another of the objects of the present invention is to provide an improved means for maintaining the configuration of a network, including additions/removals and movement of end-stations for virtual local area networks (VLANs) in a switched networking system incorporating a variety of switching devices (e.g., cell-switched, frame-switched and configuration-switched devices).

These and other objects of the present invention are provided for by a networking system and automatic method in a networking system comprising a plurality of switching devices and a plurality of end-stations interconnected with the switching devices, wherein the switching devices and end-stations are interconnected in a first topology. A configuration device is included which has a configuration modification detection circuit for detecting the modification of the first topology. A configuration policy maintenance circuit is provided for storing policies related to reconfiguring the switching devices upon the modification of the first topology. Further, a policy evaluation circuit is provided for determining which end-stations and ports should be grouped together in a first manner. Lastly, a reconfiguration circuit is provided for reconfiguring the switching devices in the network to enable end-stations and ports to be grouped in the first manner.

In implemented embodiments, the reconfiguring includes assigning newly-coupled end-stations in the networking system to virtual networks according to the policies. This process includes reconfiguring the switching devices to interconnect the end-stations and to assign the end-stations to the virtual local area networks (VLANs). The configuration modification detection circuit is implemented in one embodiment as a polling circuit for polling the switching devices in the network to determine the modification of the first topology. In another embodiment, it is implemented via traps wherein a trap reception circuit is provided for receiving traps generated by the switching devices in the network upon the modification of the first topology. Modification of the first topology may include a first end-station being removed from the network, being moved in the network, or being added to the network. Modification of the first topology may also include modification of interconnections between switching devices. If an end-station moves, network services formerly provided to the end-station may be automatically provided at its new location via the automatic reconfiguration of effected network switching devices. Predetermined network services may be made available to a new station via automatic reconfiguration of networking switching devices connected to the new station and deletion of VLAN's from effected network switching devices may be performed upon removal of end-stations.

In implemented embodiments, the policies include a member policy table specifying which end-stations should or should not be coupled together to form virtual networks. Policies may also include an override policy table specifying that certain of the end-stations should not be reconfigured. For certain policies, end-stations may be specified using certain attributes such as hardware (e.g. MAC), asynchronous transfer mode (ATM), or network address (e.g. internet protocol �IP! or IPX address), or specified ports which should be grouped together to form a VLAN. Any other attributes which may be obtained from end-stations may be used for defining policies. The policies may also include an automatic policy table specifying that VLANs should be created automatically for end-stations having certain common attributes (e.g. in the same subnet). Such policies may be defined and maintained by a user (e.g. a network manager) at a network management station for automatic implementation during network operation.

Other objects, features and advantages of the present invention will be apparent from the accompanying description and figures which follow below.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitation in the figures of the accompanying in which like references indicate like elements and in which:

FIGS. 1a and 1b illustrate block diagrams of switched inter-networks in which embodiments of the present invention may be implemented.

FIG. 2 shows a block diagram of a network device in which certain of the processes of the present invention may be implemented.

FIG. 3 shows a block diagram of processes which are active in implemented embodiments of the present invention.

FIG. 4 shows a block diagram of various processes active in an auto-configuration process.

FIGS. 5-10 show various tables which are maintained for automatic configuration of virtual local area networks in a switched networking system.

FIG. 11 shows a flowchart of the virtual auto-configuration daemon process main loop.

FIG. 12 shows a flowchart of the polling process which is used in implemented embodiments of the present invention.

FIG. 13 shows the interrelationship of the policy evaluation module with the policies and polled network data which is obtained in implemented embodiments of the present invention.

FIG. 14 shows the relationship between the policy evaluation module and the various policy tables which are maintained in implemented embodiments of the present invention.

FIGS. 15a-15b show a flowchart of the policy evaluation process.

FIG. 16 shows a flowchart of the virtual local area network creation/addition process in a single hub.

FIG. 17 shows a VLAN extension process which is performed in a networking system.

FIG. 18 shows a VLAN contraction process used in implemented embodiments of the present invention.

FIG. 19 shows an example of adding a new end-station to an inter-networking system.

FIG. 20 shows an example of moving an end-station in an inter-networking system.

DETAILED DESCRIPTION

Implemented embodiments of the present invention include methods and apparatus for automatic configuration of switched networks implementing virtual local area networks (VLANs). For the remainder of this application, as will be discussed, reference will be made to certain networking devices such as "concentrators" or "hubs" which have a plurality of plug-in modules which each have ports for connecting to different types of network cables such as fiber optic cable, unshielded twisted pair cable and shielded twisted pair cable. Reference is specifically made to U.S. Pat. No. 5,226,120 of Brown et al., (hereinafter "Brown") issued on Jul. 6, 1993, which shows in detail certain hardware structures for implementing such devices as "concentrators" and/or "hubs." The techniques to be described here are implemented in a software implementation in central processing unit(s) of device(s) in a switched networking system such as described in Brown. Although the present invention will primarily be directed towards a method which is implemented in a software code implementation which is executed at run-time in a single device and which interacts with software for communication in other networking devices, it can be appreciated by one skilled in the art that these may be implemented in any variety of dedicated hardware devices in a networking device including, but not limited to, discrete logic circuits, large sca