US 2005/0030951 A1 · Reservation protocol signaling extensions for optical switched networks

Abstract

An architecture and method for performing coarse-grain reservation of lightpaths within wavelength-division-multiplexed (WDM) based photonic burst-switched (PBS) networks with variable time slot provisioning. The method employs extensions to the RSVP-TE signaling protocol, which uses various messages to reserve resources. A resource reservation request is passed between nodes during a downstream traversal of the lightpath route connecting a source node to a destination node via one or more switching nodes, wherein each node is queried to determine whether it has transmission resources (i.e., a lightpath segment) available during a future scheduled time period. Soft reservations are made for each lightpath segment that is available using information contained in a corresponding label. If all lightpath segments for a selected route are available, a reservation response message is sent back upstream along the route from the destination node to the source node. In response to receiving the response, the soft reservations are turned into hard reservations at each node.

Claims34

Dependent claims

A method for establishing a coarse-grained reservation of a lightpath traversing a plurality of connected lightpath segments between source and destination nodes in an optical switched network, comprising:

making a soft reservation of node resources supporting respective lightpath segments from among the plurality of lightpath segments, the soft reservation of the node resources corresponding to a scheduled time period for which the lightpath is requested to be reserved;
determining if adequate node resources are available for reservation during the scheduled time period to support traversal of the entire lightpath;
and
making a hard reservation of the node resources corresponding to the scheduled time period if adequate node resources are determined to be available.

1 more element

A switching 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:
receiving a resource reservation request from a first node, said resource reservation request including data pertaining to a first lightpath segment between the first node and the switching apparatus, which comprises a second node, and a scheduled time period for which resources for the switching apparatus are requested to be reserved;
and
making a soft reservation of resources supporting communication via the first lightpath segment for the scheduled time period;
receiving a reservation response;
and
changing the soft reservation of the resources supporting communication via the first lightpath segment to a hard reservation to commit the resources for the scheduled time period.

6 more elements

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

receiving a resource reservation request from a second node, said resource reservation request including data pertaining to a lightpath segment between the second node and the switching apparatus and a scheduled time period for which resources for the switching apparatus are requested to be reserved to support communication via the lightpath segment;
determining if resources are available to support communication via the lightpath segment during the scheduled time period, and if so,
making a soft reservation of resources supporting communication via the first lightpath segment for the scheduled time period;
receiving a reservation response;
and
changing the soft reservation of the resources supporting communication via the first lightpath segment to a hard reservation to commit the resources for the scheduled time period.

3 more elements

Dependencies are inferred from the claim text.

Reservation protocol signaling extensions for optical switched networks

Life of this patent

Reservation protocol signaling extensions for optical switched networks

Life of this patent

Abstract

Claims34