US 2005/0089327 A1 · Dynamic route discovery for optical switched networks

Abstract

An architecture and method for performing dynamic route discovery and variable time slot reservation provisioning within optical-switched networks. The method employs extensions to the RSVP-TE signaling protocol, which uses various messages to reserve network resources. Under an overlay routing embodiment, network resources are reserved via a resource reservation message that is sent hop-by-hop between switching nodes, wherein the next hops are dynamically selected based on routing tree tables in the switching nodes. The concatenation of hops forms the route for the reserved lightpath. The resource reservation request is passed between nodes defined by a dynamically routed path, and resource availability is confirmed for the entire lightpath prior to confirming the resource reservations.

Claims29

Dependent claims

A method comprising:

dynamically discovering an available lightpath route comprising a concatenation of a plurality of lightpath segments connected via respective nodes along a route spanning from a source edge node to a destination edge node and including at least one switching node in an optical switched network;
and
reserving network resources to enable transmission of data between the source and destination nodes along the lightpath route during a scheduled time slot, wherein reservation of the network resources causes said at least one switching node and the source and destination edge nodes to be configured so as to form a virtual optical-switched circuit between the source and destination edge nodes during the scheduled time slot.

A switching node apparatus for use in an optical switched network, comprising:

optical switch fabric, having at least one input fiber port and at least one output fiber port;
and
a control unit, operatively coupled to control the optical switch fabric, including at least one processor and a first storage device operatively coupled to said at least one processor containing machine-executable instructions, which when executed by said at least one processor perform operations, including:
generating a routing tree table identifying applicable routes to route data between the switching node apparatus when implemented as a first node in an optical switched network and other nodes in the optical switched network;
maintaining a resource reservation table including reservations of switching node apparatus resources for scheduled time slots;
receiving a lightpath resource reservation request from a second node, said resource reservation request including data identifying an address of a destination node and a scheduled time slot for which resources for the switching node apparatus are requested to be reserved for a lightpath traversing a plurality of nodes from a source node to the destination node;
dynamically determining a third node comprising a next hop node for the lightpath based on routing information contained in the routing tree table and resource availability determined from the resource reservation table;
and
forwarding the lightpath resource reservation request to the next hop node;
and
reserving network resources corresponding to the lightpath resource reservation request to support routing of data through the switching node apparatus for the scheduled time slot.

8 more elements

A machine-readable medium to provide instructions, which when executed by a processor in a switching node apparatus comprising a first node in an optical switched network, cause the switching node apparatus to perform operations comprising:

generating a routing tree table identifying applicable routes to route data between the switching node apparatus when implemented as a first node in an optical switched network and other nodes in the optical switched network;
maintaining a resource reservation table including reservations of switching node apparatus resources for scheduled time slots;
receiving a lightpath resource reservation request from a second node, said resource reservation request including data identifying an address of a destination node and a scheduled time slot for which resources for the switching node apparatus are requested to be reserved for a lightpath traversing a plurality of nodes from a source node to the destination node;
dynamically determining a third node comprising a next hop node for the lightpath based on routing information contained in the routing tree table and resource availability determined from the resource reservation table;
and
forwarding the lightpath resource reservation request to the next hop node;
and
reserving network resources corresponding to the lightpath resource reservation request to support routing of data through the switching node apparatus for the scheduled time slot.

5 more elements

Dependencies are inferred from the claim text.

Dynamic route discovery for optical switched networks

Life of this patent

Dynamic route discovery for optical switched networks

Life of this patent

Abstract

Claims29