Adaptive channel loading in WDM optical communication systems

An apparatus, comprising:

• a channel allocation controller capable of communicating with optical nodes of an optical network and for each one of a plurality of optical fiber paths, capable of allocating an optical wavelength channel in an optical spectrum to support optical communications between a pair of optical nodes over the one of the plurality of optical fiber paths on each optical fiber span thereof;
• wherein the channel allocation controller is configured to update a channel allocation table in response to allocating an optical wavelength channel, the channel allocation table indicating those of the optical wavelength channels allocated to the optical fiber spans of the optical network;
• wherein the channel allocation controller is configured to determine the optical wavelength channel to be allocated based on a state of the optical network as defined by the allocation table and to write to the channel allocation table an indication of widths of the optical wavelength channels allocated to the optical fiber spans;
• wherein the channel allocation controller is capable of allocating, to a first optical fiber path of the optical network, an optical wavelength channel of a different width than an optical wavelength channel already allocated to a second optical fiber path thereof;
• and
• wherein the channel allocation controller is configured to define a set of optical sub-bands to cover a part of the optical spectrum in response to a state of the allocation table satisfying a fullness property, the optical sub-bands being defined such that each of the allocated wavelength channels is located in one of the optical sub-bands.

A method comprising:

• for each one of a plurality of optical fiber paths in an optical network, allocating an optical wavelength channel in an optical spectrum such that the allocated optical wavelength channel is assigned to support optical communications over one of the optical fiber paths on each optical fiber span thereof;
• updating a channel allocation table in response to performing the allocating for one or more of the optical fiber paths, the channel allocation table indicating optical wavelength channels allocated to the optical fiber spans of the optical network, the act of allocating including determining the optical wavelength channel to be allocated based on a state of the optical network as defined by the channel allocation table;
• and
• defining a set of optical sub-bands to cover a part of the optical spectrum in response to a state of the channel allocation table satisfying a fullness property, the optical sub-bands being defined such that each of the allocated wavelength channels is located in one of the optical sub-bands.

An apparatus, comprising:

• a channel allocation controller capable of communicating with optical nodes of an optical network and for each one of a plurality of optical fiber paths, capable of allocating an optical wavelength channel in an optical spectrum to support optical communications between a pair of optical nodes over the one of the plurality of optical fiber paths on each optical fiber span thereof;
• and
• wherein the channel allocation controller is configured to update a channel allocation table in response to the allocating an optical wavelength channel, the channel allocation table indicating those of the optical wavelength channels allocated to the optical fiber spans of the optical network;
• wherein the channel allocation controller is configured to determine the optical wavelength channel to be allocated based on a state of the optical network as defined by the allocation table;
• and
• wherein the channel allocation controller is configured to define a set of optical sub-bands to cover a part of the optical spectrum in response to a state of the allocation table satisfying a fullness property, the optical sub-bands being defined such that each of the allocated wavelength channels is located in one of the optical sub-bands.