Distributed switch and connection control arrangement and method for digital communications network

• US 6,791,948 B1
• Filed: 12/27/1999
• Issued: 09/14/2004
• Est. Priority Date: 05/02/1998
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Emulex Corporation (Broadcom, Inc.)
• Inventors: Clayton, Shawn A., Godiwala, Nitin D., Desnoyers, Peter J.
• Primary Examiner(s): VANDERPUYE, KENNETH N
• Application Number:
  US09/347,709
• Time in Patent Office: 1,723 Days
• Field of Search: 370/254, 370/255, 370/256, 370/257, 370/408, 370/395.1, 370/238, 370/389, 370/351
• US Class Current: 370/254
• CPC Class Codes: H04L 45/02 Topology update or discovery

Abstract

A network includes devices such as computers and the like, interconnected by switching nodes. The devices are identified by globally-unique identifiers, such as Ethernet MAC addresses or the like. At least some of the devices are configured to determine the topology of the network. In determining the network topology, a device operates in a series of iterations, in each iteration transmitting a request message over a path to determine whether an additional entity is present in the network. If an additional entity is present at the end of the path defined in the request message, the entity will generate a response, which is provided to the device. The device, on receiving the response, will add information concerning the entity to a network topology database, which it maintains to define the topology of the database. At least some of the devices, as they discover additional switching nodes in the network, will attempt to configure the switching nodes. In that operation, the devices interact with the switching nodes in connection with a locking protocol to ensure that only one device attempts to configure each switching node. Each device, after it determines the network topology, and when it needs to transfer information with another device, can determine an appropriate route using the network topology information in its network topology database. After determining the appropriate route, the devices will load routing information into the switching nodes to enable them to forward messages containing the information to be transferred thereamong. Each device will provide to the other devices its globally-unique address, which the other devices use to identify the respective device.

Claims

1. A network comprising:

a plurality of network entities, including message generating devices and switching nodes, the switching nodes interconnecting the message generating devices to enable the message generating devices to transfer information thereamong,

A. each entity being configured to, in response to receipt of an identification request message directed thereto, generate an identification response message identifying the entity and providing reception path information identifying a path over which the entity received the identification request message and transmit the identification response message over the path; and

B. at least one device including a network topology database configured to store network topology information representative of the interconnection topology in the network and a network topology determination processor configured to determine network interconnection topology information for use in the network topology database, the network topology determination processor being configured to operate in a series of iterations, in each iteration enabling the device to transmit an identification request message over a path in the network to determine whether an entity is present in the network at the end of the path defined in the identification request message, the path extending over one or more entities, and, upon receipt of an identification response message responding to the identification request message, obtain the entity identification and path information therefrom for use in the network topology database.

2. A network as defined in claim 1 in which at least one device further includes a switching node configuration processor configured to, after receiving an identification response message from an entity, selectively initiate a configuration operation in connection with the entity to provide at least one operational parameter to the entity.

3. A network as defined in claim 2 in which switching node configuration processor initiates a configuration operation in connection with the entity if the entity is a switching node.

4. A network as defined in claim 3 in which the switching node configuration processor is configured to initially perform a locking operation to attempt to lock the switching node.

5. A method of facilitating discovery by a device connected to a network of network topology information, the network including a plurality of network entities, including message generating devices and switching nodes, the switching nodes interconnecting the message generating devices to enable the message generating devices to transfer information thereamong, the device being connected to one of said network entities, the method comprising the steps of, in at least one iteration:

A. enabling the device to transmit an identification request message over a path in the network to determine whether an entity is present in the network at the end of the path defined in the identification request message, the path extending over one or more entities;

B. in response to receipt by a first entity of an identification request message directed thereto, enabling the first entity to generate an identification response message identifying the first entity and provide reception path information identifying a path over which the first entity received the identification request message, and transmit the identification response message over the path to the device;

C. enabling the device, after receiving an identification response message, to obtain the first entity identification and path information therefrom for use in a network topology database; and

D. operating in a series of iterations, in each iteration enabling the device to transmit an identification request message along a path including the first entity to determine whether another entity is coupled to the first entity and, upon receipt of an identification response message responding to the identification request message, obtain entity identification and path information from the identification response message for use in the network topology database.

6. A method as defined in claim 5 in which the device is further enabled to, after receiving an identification response message from an entity, selectively initiate a configuration operation in connection with the entity to provide at least one operational parameter to the entity.

7. A method of facilitating discovery by a device connected to a network of network topology information, the network including a plurality of network entities, including message generating devices and switching nodes, the switching nodes interconnecting the message generating devices to enable the message generating devices to transfer information thereamong, the device being connected to one of said network entities, the method comprising the steps of, in at least one iteration:

A. enabling the device to transmit an identification request message over a path in the network to determine whether an entity is present in the network at the end of the path defined in the identification request message, the path extending over one or more entities;

B. in response to receipt by an entity of an identification request message directed thereto, enabling the entity to generate an identification response message identifying the entity and provide reception path information identifying a path over which the entity received the identification request message, and transmit the identification response message over the path;

C. enabling the device, after receiving an identification response message, to obtain the entity identification and path information therefrom for use in a network topology database;

D. after receiving an identification response message from an entity, enabling the device to selectively initiate a configuration operation in connection with the entity to provide at least one operational parameter to the entity; and

E. enabling the device to initiate a configuration operation in connection with the entity if the entity is a switching node.

8. A method as defined in claim 7 in which the device is enabled to initially perform a locking operation to attempt to lock the switching node.