Cisco Technology, Inc.

David Bianchi

Maurizio Gazzola

Gilberto Loprieno

Luca Della Chiesa

Gabriele Maria Galimberti

Stefano Binetti

Giovanni Martinelli

Giovanni Tandi

Stefano Piciaccia

Anand Girish Parthasarathy

Ornan Alexander Gerstel

Alberto Arnaldo Tanzi

Giacomo Losio

Ya Xu

Emanuela Grandi

Moustafa Kattan

Maruizio Gazzola

Jeffrey Douglas Maddox

Ronald Dale Johnson, Jr

Jr Ronald Dale Johnson

An optical network packet configured to transmit over an optical communication link from a first optical network having a first control plane to a second optical network having a second control plane is generated. Generating the optical network packet comprises generating the packet configured to be transmitted from the first optical network to the second optical network in the optical domain.

Optical multiplex level and optical channel layer server trails in wavelength switched optical networks

Techniques are provided for using light path priority of service information in an optical network. At a node in the optical network, priority of service information is stored for a plurality of light paths used in the optical network. The node serves traffic in the optical network using the plurality of light paths based on the priority of service information. These techniques provide for prioritizing light paths (wavelengths) for scenarios such as restoration, congestion and resource contention.

Light path priority in dense wavelength division multiplexed networks

In an OTN (Optical Transport Network), an OTN interface of a network element may receive a BDI (Backwards Defect Indicator) signal from a far end network element to which OTN frames are being transmitted. A BDI signal indicates the occurrence of a unidirectional failure in the transmission of OTN frames to which the far end network element responds by switching its routing to the network element. The OTN interface generates an AIS (Alarm Indication Signal) for its network element so that the network element switches network communication channels to the far end network element to ensure bidirectional switching upon a unidirectional failure.

Response to OTUk-BDI for OTN interfaces to restore bidirectional communications

Techniques and a control architecture (apparatus and logic) are provided for an adaptive hybrid DWDM-aware computation scheme. The architecture is one that is a hybrid of a centralized control scheme and a distributed control scheme that performs adaptive physical impairment computations for an optical network. A central control server is connected to multiple client control devices each of which resides in a node in a dense wavelength division multiplexed (DWDM) optical network, wherein each client control device is part of an optical control plane associated with the optical network. The control server obtains data for path route analysis from the client control devices. The control server then determines optical feasibility of at least one path route from a source node to a destination node from optical parametric information based on the data obtained from multiple client control devices and without real-time communication between the central control server and the multiple client control devices while performing the optical feasibility computations.

Adaptive hybrid optical control plane determination of lightpaths in a DWDM network

Various example embodiments are disclosed. According to an example embodiment, a method may include receiving a resource request for optical resources within a wavelength division multiplexed (WDM) optical network; comparing one or more parameters of the resource request to a list of pre-validated paths for the WDM optical network, each pre-validated path identifying an optically feasible label switched path between a source node and a destination node; determining that there is a pre-validated path on the list that matches the one or more parameters of the optical resource request; and sending a message to request a reservation of resources along the matching pre-validated path.

Use of pre-validated paths in a WDM network

Methods and apparatus for efficiently allowing protection switch information to be communicated on bidirectional lines are disclosed. According to one aspect of the present invention, a method for communicating protection switch information from a first network element to a second network element across bidirectional links that include at least one working line and a protection line involves obtaining a generic framing procedure GFP frame at the first network element. The GFP frame has a payload area with a client payload field. The method also includes defining a command field associated with the GFP frame that is in the payload area but not in the client payload field, and storing protection switch information in the command field.

Smart mechanism for multi-client bidirectional optical channel protection scheme

In one embodiment, a SONET/SDH over Ethernet demapping point utilizes a pointer offset mechanism for clock recovery and timing. The pointer offset is determined by the difference between a client clock and a reference clock.

Pointer offset mechanism enabling cost effective SONET/SDH mapping/demapping over ethernet

Techniques are provided for detecting at a controller associated with a physical layer of a network an occurrence of a failure within the physical layer of the network. In response to detecting the failure, the controller sends messages to at least first and second nodes in a transport layer of the network, where the messages are configured to indicate normal operations in the physical layer so as to prevent execution of transport layer protection processes for a period of time.

Smart protection escalation mechanism prevention

Systems and methods for unidirectional communication in an optical network employing bidirectional transponders are provided. The modulation and amplification capabilities of the bidirectional transponder are used to forward information to the next node. In this way a highly cost-effective 'drop and continue' architecture is provided. In one implementation, the client-side output of the bidirectional transponder is looped back to the client-side input using, e.g., a Y-cable fiber. In this way, a unidirectional signal present on a network-side input wavelength to the transponder is presented both on a network-side output wavelength of the transponder and at the same time to a client. The modulation and amplification capabilities of the bidirectional transponder are thus exploited in forwarding the unidirectional signal to the next node.

Unidirectional drop and continue using bidirectional transponder

Systems and methods for operating transponders that automatically accommodate multiple received signal types. The different signal types may include different clients such as, e.g., SONET/SDH, G.709, 10 Gigabit Ethernet, etc. as well as different data rates. A transponder can automatically detect the client signal type and data rate and respond by processing the received signal appropriately, notifying a control processor, and invoking an appropriate performance monitoring method. This maximizes the network operator's flexibility and ease of configuration.

Automatic selection of the performance monitoring based on client type

Methods and apparatus for allowing a dense wave division multiplexing (DWDM) line card w to function as an add/drop multiplexer (ADM), a transponder, and a muxponder are disclosed. According to one aspect of the present invention, a line card suitable for use in a network to aggregate signals of different line rates for transport includes a first arrangement having ADM functionality, a second arrangement having transponder functionality, and a third arrangement having muxponder functionality. The line card also includes hardware that facilitates communication between the arrangements, as well as a plurality of ports arranged to receive a signal and to provide the signal to the hardware.

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Cambiago, Italy

David Bianchi