Lucent Technologies Inc.

Stevens Institute of Technology

Tai H Noh

Dhadesugoor R Vaman

Jon Anderson

Curtis J Newton

Jay D Bose

A layered bandwidth management system for transporting both STM and ATM traffic from customer circuit elements over a synchronous digital hierarchical (SDH (SONET)) transport network comprises a hybrid transport device for separately transporting STM and ATM traffic over separate first physical channels, the physical channels having fixed bandwidth allocations; a first bandwidth control device responsive to STM traffic contained in the first physical channel for directing STM traffic in fixed bandwidth allocations to a further destination; and, a second bandwidth control device responsive to ATM traffic contained in a separate first physical channel for switching the ATM traffic to a further destination, the second bandwidth control device capable of directing ATM traffic to the first physical channels for more efficient physical channel bandwidth utilization.

Layered bandwidth management in ATM/SDH (SONET) networks

A method and apparatus for the transparent, non-disruptable transfer of data, particularly multimedia data, through any packet-based network, such as an ATM network is provided. The method of the present invention includes the step of setting a primary path and a secondary path between nodes of a network, or of a network domain. Accordingly, when a switch or node establishes a Virtual Path (VP) to another switch with specified effective bandwidth, it also has an alternate VP that is available, although no bandwidth is actually used. The method of the present invention further includes the step of optimizing the available capacity of the system through management actions. For handling congestion and resource failures, the total effective bandwidth on each physical link is categorized in terms of idle capacity (unused or available), used capacity (for existing VPs), and spare capacity. When a resource failure occurs, the idle capacity is used for real-time switching of the VP and service is not disrupted. This is accomplished by an alarm indication management cell which is delivered when a resource problem is encountered. This management cell sets forth the secondary path and the bandwidth associated therewith. On the other hand, if idle capacity does not exist, the spare capacity is used, while the bandwidth of all other VPs is reconfigured using virtual bandwidth optimization. Therefore, service disruption does not occur. In a wireless, mobile network, the present invention monitors node movement and takes management actions on the basis of such node movement to prevent service disruption.

Transparant non-disruptable ATM network

A Virtual Path Group (VPG) technique that utilizes network elements (NEs), i.e., nodes, that are visible to ATM specific defects, and allows for fast ATM virtual connection/restoration with a minimum of processing. This is realized by employing a Virtual Path Group transport architecture comprises at least one (1) working route, one (1) protection route, and VPG bridge and selector functions at each end of the routes. It is applicable to 1+1, mesh and ring protection switching and is extensible to any virtual connection segment or end-to-end network (cross-subnetwork) virtual connections, and extensible to 1:1 and M:N protection switching. Additionally, the protection switching arrangement of the invention includes an architecture for the Virtual Path Group (VPG) concept in which the associations among individual ATM virtual channels (VP/VCs) and VPGs are maintained entirely within the network element management function. This allows VPG support to be added to ATM systems and networks with minimum change from current ATM standards. In particular, no changes are required to the Virtual Path Identifier/Virtual Channel Identifier (VPI/VCI) addresses carried within each ATM cell across ATM interfaces. Further, defect type indication is realized via a new, for example a F4, segment level Operation and Maintenance (OAM) cell, to initiate the appropriate restoration action downstream. The technique differentiates between physical layer and ATM layer defects. An algorithm is employed in an embodiment of the invention to determine appropriate VPG protection switch and signaling actions, driven by the F4 defect type OAM cells. Moreover, for interworking with physical layer protection (e.g. SONET Bi-Directional Line Switched Ring (BLSR)), a VPG protection holdoff function is employed at the VPG protection selector. A technical advantage of this protection switching invention is that it provides extremely fast protection switching of an extremely large number of ATM virtual connections.

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Manalapan, NJ, United States of America

Tai H Noh