Detection of a relative location of a network device using a multicast packet processed only by hubs

• US 5,421,024 A
• Filed: 08/30/1993
• Issued: 05/30/1995
• Est. Priority Date: 04/30/1991
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Black, Chuck A., Faulk, Robert L. Jr.
• Primary Examiner(s): Bowler, Alyssa H.
• Assistant Examiner(s): GECKIL, MEHMET B
• Application Number:
  US08/114,116
• Time in Patent Office: 638 Days
• Field of Search: 395/200, 395/800, 370/85.12, 370/85.13, 370/85.15
• US Class Current: 709/223
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04L 45/36 Backward learning

Abstract

Within a network, which includes hubs and bridges, the relative location of a first device with respect to a subset of hubs on the network is determined. In response to an instruction, the first device broadcasts a multicast packet. The multicast packet crosses bridges and is processed only by hubs. When a hub receives the multicast packet from the first device, the hub records a first port of the hub over which the second device received the multicast packet. The subset of hubs may then be interrogated to determine over which port of each of the subset of hubs the multicast packet was received.

Claims

1. Within a network which includes hubs for connecting network stations within local networks and bridges for providing connection between local networks, a method comprising the step of:

(a) detecting, by a mapping application within a first network station, a relative location of a first hub with respect to a subset of hubs and bridges on the network, the first network station being included in the network, including the substeps of,

(a.1) instructing, by the mapping application within the first network station, each hub and bridge within the subset of hubs and bridges to listen for multicast packets from the first hub,

(a.2) instructing, by the mapping application within the first network station, the first hub to broadcast a multicast packet, the multicast packet crossing bridges and being processed only by hubs and bridges,

(a.3) when one of the subset of hubs and bridges receives the multicast packet from the first hub, recording, by the one of the subset of hubs and bridges, a first port over which the multicast packet was received, and

(a.4) interrogating, by the mapping application within the first network station, the subset of hubs and bridges to determine over which port of each of the subset of hubs and bridges the multicast packet was received.

2. A network comprising:

a plurality of interconnected hubs and bridges, the hubs connecting network stations within local networks and the bridges providing connection between local networks, each hub and bridge including

means for detecting over what port a packet is received, and

recording means for, when a multicast packet is received, recording a first port over which the multicast packet is received; and

,

a first network station having a mapping application, the mapping application determining relative location of a first hub with respect to a subset of hubs and bridges on the network, the mapping application including

means for directing the subset of hubs and bridges to listen for a multicast message from the first hub,

means for instructing the first hub to broadcast a multicast packet, wherein the multicast packet is processed only by hubs and the multicast packet goes through the bridges, and

interrogating means for interrogating the subset of hubs and bridges to determine over which port of each of the subset of hubs and bridges the multicast packet was received.