Device and method for interconnecting distant networks through dynamically allocated bandwidth

• US 6,658,457 B2
• Filed: 11/18/1999
• Issued: 12/02/2003
• Est. Priority Date: 03/19/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nishikawa, Hiroshi, Suzuki, Ayako, Motoyama, Hideyuki
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): DINH, KHANH Q
• Application Number:
  US09/442,883
• Publication Number:
  US 20030187934A1
• Time in Patent Office: 1,475 Days
• Field of Search: 709/206, 709/217, 709/222, 709/224, 709/225, 709/227, 709/228, 709/230, 370/223, 370/230, 370/468
• US Class Current: 709/206
• CPC Class Codes: H04L 12/5602 Bandwidth control in ATM Networks, e.g. leaky bucket

Abstract

An internetworking device and method which interconnects distant networks through an intermediary transport network, employing a bandwidth allocating mechanism to enable efficient and transparent LAN-to-LAN communication. A network interface unit provides communication interface functions to link with each network to be connected. Data traffic between the networks is observed by a traffic monitor and reported to a bandwidth allocation controller. A bandwidth resource database stores information on the usage of bandwidth resources. When a certain node in one network attempts to send data packets toward the other network, the bandwidth allocation controller dynamically allocates sufficient bandwidth resources to the requested connection, based on the reported data traffic and the information stored in the bandwidth resource database. With the allocated bandwidth, packets are transported to the destination under the control of a communication controller.

Claims

1. An internetworking device which connects a first network to a second network through a transport network that conforms to SONET or SDH standards, the transport network being assigned a predetermined amount of SONET or SDH path resources, the internetworking device comprising:

network interface means for providing a communication interface to link with the first network;

traffic monitoring means for monitoring data traffic from the first network to the second network;

bandwidth resource information storage means for storing information on path resources of the transport network;

bandwidth allocating means for dynamically increasing bandwidth of the transport network by allocating an additional path to the transport network, consulting said bandwidth resource information storage means, when said traffic monitoring means detects increasing data traffic from the first network; and

communication control means for controlling data transport from the first network to the second network using the increased bandwidth of the transport network.

2. The internetworking device according to claim 1, wherein said traffic monitoring means foresees an increase in the data traffic when the first network shows activities of such an application that tends to produce a large amount of network traffic.

3. The internetworking device according to claim 1, wherein said traffic monitoring means monitors the data traffic by watching an occupancy level of a buffer memory temporarily storing the data streams being transported from the first network to the second network.

4. The internetworking device according to claim 1, wherein said traffic monitoring means monitors the data traffic by watching packet intervals of the data streams being transported from the first network to the second network.

5. The internetworking device according to claim 1, wherein said traffic monitoring means receives a traffic request message which specifies a desired bandwidth.

6. The internetworking device according to claim 1, wherein said bandwidth allocating means allocates the additional path according to parameters given by a user of the networks.

7. The internetworking device according to claim 1, wherein said bandwidth allocating means dynamically allocates a combination of additional paths to the transport network when the data traffic is high.

8. The internetworking device according to claim 1, wherein said bandwidth allocating means dynamically reallocates a path with a higher bitrate when the data traffic is high.

9. The internetworking device according to claim 1, wherein:

the transport network provides redundant transmission subsystems including a working subsystem and a protection subsystem; and

said bandwidth allocating means allocates paths on the protection subsystem when the data traffic is high.

10. The internetworking device according to claim 1, wherein said bandwidth allocating means allocates a predetermined path resource to the data traffic related to a particular node on the networks.

11. The internetworking device according to claim 1, wherein said bandwidth allocating means dynamically allocates a path on a protection ring to transport the data streams, when the transport network is of Uni-directional Path Switched Ring (UPSR) configuration.

12. The internetworking device according to claim 1, wherein said bandwidth allocating means dynamically allocates a free time slot as a bandwidth resource to transport the data streams, when the transport network is of Bi-directional Line Switched Ring (BLSR) configuration.

13. The internetworking device according to claim 1, further comprising phase compensation means for correcting alignment of the data streams by compensating for phase variations caused by traveling over different paths.

14. An internetworking method to connect a first network to a second network through a transport network that conforms to SONET or SDH standards, the transport network being assigned a predetermined amount of SONET or SDH path resources, the method comprising the steps of:

(a) providing a communication interface to link with the first network;

(b) monitoring data traffic from the first network to the second network;

(c) providing a database storing information on path resources of the transport network;

(d) dynamically increasing bandwidth of the transport network by allocating an additional path to the transport network, consulting the database of path resource information, when increasing data traffic from the first network is detected; and

(e) controlling data transport from the first network to the second network using the increased bandwidth of the transport network.

15. The internetworking method according to claim 14, wherein said step (d) of bandwidth allocation dynamically allocates the additional path according to parameters given by a user of the networks.

16. The internetworking method according to claim 14, wherein said step (d) of bandwidth allocation uses a protection subsystem as an additional path a resource to be allocated, when the transport network provides redundant transmission subsystems.