System for inference of presence of network infrastructure devices

• US 7,307,962 B2
• Filed: 03/02/2001
• Issued: 12/11/2007
• Est. Priority Date: 03/02/2001
• Status: Expired due to Term

• Current Assignee: Valtrus Innovations Limited (f/k/a Dolya Holdco 9 Limited) (Key Patent Innovations Limited)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Pulsipher, Eric A
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Hom, Shick
• Application Number:
  US09/796,708
• Publication Number:
  US 20020124079A1
• Time in Patent Office: 2,475 Days
• Field of Search: 370/230, 370/236, 370/236.1, 370/236.2, 370/252, 370/254, 370/255, 709/202, 709/220, 709/223, 709/224, 709/225
• US Class Current: 370/254
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC

Abstract

A device discovery module of a network management software is utilized to discover the presence of layer-2 network devices. When enabled by a command from the network management software, the device discovery module may be configured to query or poll all network devices for information. The device discovery module may be configured to seek address information from an address resolution protocol (“ARP”) cache of a queried network device. The ARP cache may contain addresses, e.g., layer-2 address, of other network devices contacted by the queried network device. The device discovery module may be further configured to retrieve from the queried network device the port type and port configuration. After retrieving the address information, the device discovery module organizes the address information in an ordered list starting with the identified port of a network device and address information detected on the identified port. If the identified port has been identified as a single point-to-point connection, and there are multiple address detected on that port, this is an inference that there is a device connecting the remote device of the identified port with the devices of each address heard. Otherwise, if the identified port has been identified as a single point-to-point connection, and there is only one address detected, this is an inference that there are no intervening devices.

Claims

1. A method for determining a topology of a network comprising:

querying a plurality of known remote devices in the network for layer-2 address information, said layer-2 address information comprising layer-2 addresses detected at each port of said plurality of known remote devices;

querying at least a first of said plurality of known remote devices for a type of connection for at least a first port of the first known remote device;

inferring an unmapped remote device is physically connected to the first port of the first known remote device based on an identification that the first port has a point to point connection type and that the first port has detected a plurality of layer-2 addresses; and

inferring a direct connection between a second and a third remote device of said plurality of known remote devices in response to an identification of a single detected layer-2 address of said third known remote device for one port of said second known remote device.

2. The method of claim 1,

wherein querying at least a first of said plurality of known remote devices for a type of connection for at least a first port of the first known remote device comprises querying said plurality of known remote devices for port information, said port information comprising a type of connection for each port of each of said plurality of known remote devices;

and wherein the method further comprises;

storing in a memory said port information and said layer-2 address information for each of said plurality of known remote devices.

3. The method of claim 1, wherein querying said plurality of known remote devices for layer-2 address information comprises:

querying an address resolution protocol cache of each of said plurality of known remote devices for said layer-2 address information.

7. The method of claim 1, further comprising:

receiving a command to determine a configuration of said network, wherein said querying a plurality of known remote devices for layer-2 address information is performed in response to said receipt of said command.

8. The method of claim 2, further comprising:

displaying a network topology map including said known and unmapped remote devices in response to a second command to display said network topology map.

4. A system for determining a network topology, comprising:

at least one processor;

a memory coupled to said at least one processor; and

a network management software, residing in said memory and executing on at least one processor, configured to query a plurality of known remote devices in the network for a connection type for each port of said plurality of known remote devices and layer-2 address information, said layer-2 address information comprising layer-2 addresses detected at each port of said plurality of known remote devices, and to infer an unmapped remote device is physically connected to a first of said plurality of known remote devices based on an identification of a plurality of detected layer-2 addresses for a first port of said first remote devices and a determination that the first port of said first remote device has a point to point connection type; and

wherein said network management software is further configured to infer a direct connection between a second and a third remote device of said plurality of known remote devices in response to an identification of a single detected layer-2 address of said third known remote device for one port of said second known remote device.

5. The system of claim 4, wherein:

said network management software is further configured to query said plurality of known remote devices for port information, said port information comprising a type of connection for each port of each of said plurality of known remote devices, and to store in a memory said port information and said layer-2 address information for each of said plurality of known remote devices.

6. The system of claim 5, wherein:

said network management software is further configured to query an address resolution protocol cache of each of said plurality of known remote devices for said layer-2 address information.

11. The system of claim 4, wherein said network management software is further configured to receive a command to determine a configuration of said network, wherein said network management software queries a plurality of known remote devices for layer-2 address information is performed in response to said receipt of said command.

12. The system of claim 4, wherein said network management software is further configured to display a network topology map including said known and unmapped remote devices in response to a second command to display said network topology map.

9. A method for determining a topology of a network comprising:

querying a plurality of known remote devices in the network for layer-2 address information, said layer-2 address information comprising layer-2 addresses detected at each port of said plurality of known remote devices;

querying said plurality of known remote devices for port information, said port information comprising a type of connection for each port of each of said plurality of known remote devices;

storing in a memory said port information and said layer-2 address information for each of said plurality of known remote devices;

grouping said port information and said layer-2 address information for each remote device of said plurality of remote devices; and

inferring an unmapped remote device is physically connected to a first of said plurality of known remote devices based on an identification of a plurality of detected layer-2 addresses for a first port of said first remote device and a determination that the type of connection for the first port of said first remote device is a point to point connection type.

10. The method of claim 9, wherein grouping said port information and said layer-2 address information for each remote device of said plurality of remote devices comprises:

organizing said port information and said layer-2 address information in an ordered list starting with ports of said each remote device and said layer-2 address information detected on each of said ports.

13. A system for determining a network topology, comprising:

at least one processor;

a memory coupled to said at least one processor; and

a network management software, residing in said memory and executing on at least one processor, configured to query a plurality of known remote devices in the network for layer-2 address information, said layer-2 address information comprising layer-2 addresses detected at each port of said plurality of known remote devices;

wherein said network management software is further configured to query said plurality of known remote devices for port information, said port information comprising a type of connection for each port of each of said plurality of known remote devices, and to store in a memory said port information and said layer-2 address information for each of said plurality of known remote devices;

wherein said network management software is further configured to group said port information and said layer-2 address information for each remote device of said plurality of remote devices; and

wherein said network management software is further configured to infer an unmapped remote device is physically connected to a first of said plurality of known remote devices based on an identification of a plurality of detected layer-2 addresses for a first port of said first remote devices and a determination that the first port of said first remote device has a point to point connection type.

14. The method of claim 13, wherein said network management software is further configured to organize said port information and said layer-2 address information in an ordered list starting with ports of said each remote device and said layer-2 address information detected on each of said ports.

15. A system for determining a network topology, comprising:

means for querying a plurality of known remote devices in the network for a connection type for each port of said plurality of known remote devices and layer-2 address information, said layer-2 address information comprises layer-2 addresses detected at each port of said plurality of known remote devices; and

means for inferring an unmapped remote device is physically connected to a first of said plurality of known remote devices based on an identification of a plurality of detected layer-2 addresses for a first port of said first remote device and a determination that the first port of said first remote device has a point to point connection type; and

means for inferring a direct connection between a second and a third remote device of said plurality of known remote devices in response to an identification of a single detected layer-2 address of said third known remote device for one port of said second known remote device.