Ciena Corporation

Ciena Coporation

Ciena Luxembourg S.a.r.l.

Vagish Madrahalli

Richard W Conklin

Jeffrey Scott Moynihan

Neena Aluri

Alexander A Smith

Matthew William Connolly

John K Oltman

Bhavesh Nisar

Alessandro Fabbri

Lyndon Y Ong

Waseem Reyaz Khan

Gustav Larsson

Hongxing Meng

Yalin Wang

Iwan Kartawira

Kelai Shi

Kumaresh Malli

Purushothaman Saravanan

Jack Oltman

Steven P Curtis

Nilesh Patil

Satish Gopalakrishan

Xuan Zheng

Zhiwei Rong

Matt Connolly

Richard Conklin

A network element, in a control plane enabled network, configured to retain a connection's home path while the connection is on an alternate path includes interfaces communicatively coupled to the network to form one or more links; circuitry communicatively coupled to the interfaces, wherein the circuitry is configured to route one or more connections which originate on the network element to the one or more links via the interfaces, wherein each of the one or more connections has an associated home path, and for a connection of the one of more connections which is not on its associated home path, reserve bandwidth for the connection through the control plane on the associated home path.

Retention of a sub-network connection home path

Embodiments of the present invention provide a method and system for reserving a connection's home path resources and restoring the connection on a link that includes a reserved priority bandwidth. A bandwidth advertisement indicating that the reserved priority bandwidth is available is analyzed and a restoration request requesting to route the connection on the link is sent. The reserved priority bandwidth is used to route the connection when the connection has a reserved home path on the link. When the connection has a reserved home path not on the link, a determination is made as to whether a normal priority bandwidth on the link is available and whether the connection is unrestorable on another link. The reserved priority bandwidth is used to temporarily route the connection when normal priority bandwidth on the link is unavailable and the connection is unrestorable on another link.

The present disclosure provides dynamic service provisioning by creating embedded Optical Transport Network (OTN) ports on the fly during mesh restoration or circuit provisioning. These dynamically provisioned ports are referred to herein as 'fast paths' with all the management objects created in a 'slow path' so that they do not interfere with mesh restoration performance. During network failures, these dynamically created objects are deleted via the &#x201c;slow path&#x201d; and a new mesh path supports &#x201c;fast path&#x201d; creation of these objects. This results in substantial increase in mesh performance and also provides enhancements for operators allowing a &#x201c;Click and Go&#x201d; model to provision circuits across a network. This also reduces routing scaling issue as the routing itself is against the OTU level and not against the embedded lines.

Dynamic trail termination point creation for optical transport networks

An Optical Transport Network (OTN) mode management system includes a controller communicatively coupled to at least one OTN port. The controller is configured to operate an OTN line Optical channel Data Unit level k (ODUk) mode management system for the at least one OTN port, and the OTN line ODUk mode management system is configured to support different multiplexing scenarios on the OTN port with no loss of control plane packets on aggregated links. A network element includes at least one port with a plurality of lines associated therewith, a controller communicatively coupled to the at least one port, and an OTN line ODUk mode management system executed on the controller for managing the plurality of lines on the at least one port. A method includes configuring and dynamically managing modes of a plurality of OTN lines in a link.

Optical transport network line management system and methods

The present disclosure provides systems and methods for making latency measurements and using these measurements in routing in optical networks. In an exemplary embodiment, a method is defined whereby two nodes sharing a line automatically determine whether both nodes are capable of making a latency measurement and then which node will initiate and which node participates in making the latency measurement. In another exemplary embodiment, an on-demand latency measurement may be made between any two arbitrary nodes within a domain. Routing messages may be used to disseminate the latency of links via a signaling and routing protocol. Advantageously, the present invention provides measurement of latency and latency variation of customer circuits (i.e., SNCs) using an in-band, non-intrusive calculation with a high-degree of accuracy. Furthermore, the present invention may consider these calculations for circuit routing based on the latency and circuit acceptance based on maximum latency restrictions.

Systems and methods of measuring latency and routing thereon in optical networks

A method and system for determining timers in a High Level Data Link Control (HDLC) Traffic Manager (HTM) state machine are disclosed. According to one aspect, the invention provides for determining a transit delay between two nodes by sending a first packet having a delay measurement byte to a second node that is on a link between the first node and the second node. A measured delay value is determined based on the delay between a time of sending the first packet to the second node and receiving a second packet from the second node. The timer values of the HTM state machine are set based on the measured delay value.

Method and system for optical network smart timer management via delay measurement between spans

The present disclosure provides systems and methods for mesh restoration based on Associated Hop Designated Transit Lists (DTLs). The Associated Hop DTLs are calculated through a global restoration calculation (GRC) algorithm that can be run by a central controller in an offline manner. The restoration paths calculated by the GRC algorithm can then be pushed down to the originating nodes for each connection to utilize at the time of a given failure scenario. This GRC algorithm can be performed for each possible bundle failure in the network, where a bundle failure is determined by the set of all links which may fail together due to common shared risk, such as a common conduit or DWDM fiber. The globally calculated, contention free, restoration paths are then pushed down to each node in the network.

Methods and systems for mesh restoration based on associated hop designated transit lists

Apparatuses and methods for merging multiple domains into a merged domain and splitting a single domain into multiple domains in an Automatically Switched Optical Network (ASON) are disclosed. For merging, a node in a first domain can be identified to be a new Routing Controller (RC) for the merged domain. A second domain can be identified to be merged with the first domain. Nodes, including old RCs, in the first domain and the second domain are notified of the identity of the new RC in the merged domain. The topology of the old RC's domain is sent to the new RC. The new topology is computed by the new RC from the topology information given by the old RCs. The updated topology is distributed to nodes in the merged domain via the new RC.

Splitting and merging routing domains

The present disclosure provides absolute route diversity (ARD) for mesh restorable sub-network connection protection (MR-SNCP) services. ARD addresses concerns in MR-SNCP by providing absolute path diversity between both paths (e.g., peer Sub Network Connections (SNCs)) of an MR-SNCP connection. If an ARD condition is not met, the peer SNC is not mesh restored and the MR-SNCP works with just one single SNC. The advantage of this approach is to reuse the bandwidth saved from ARD for other MR-SNCP, i.e. more efficient bandwidth utilization due to ARD for other MR-SNCPs, and better service quality guarantee (protection) in terms of planning and managing the network bandwidth.

Systems and methods for absolute route diversity for mesh restorable connections

The present disclosure provides mesh restoration systems and methods with Optical Transport Network (OTN) links using a signaling and routing protocol, such as Optical Signaling and Routing Protocol (OSRP), Automatically Switched Optical Network (ASON), Generalized Multi Protocol Label Switching (GMPLS), and the like. The present invention includes an optical node, network, and method using the signaling and routing protocol for OTN lines of differing bandwidth granularities. The present invention utilizes OTN overhead for in-band signaling and may include capability for supporting SONET/SDH lines as well as OTN lines in the same system using the signaling and routing protocol.

Mesh restoration in optical transport networks

The present disclosure provides improvements with respect to in-band control plane signaling, virtualized channels, and tandem connection monitoring in optical networks utilizing Synchronous Optical Network (SONET), Synchronous Digital Hierarchy (SDH), Optical Transport Network (OTN), and the like. In an exemplary embodiment, the present disclosure includes an optical network operating a control plane with in-band signaling utilizing SONET/SDH path level overhead. In another exemplary embodiment, the present disclosure includes an optical network operating virtualized SONET/SDH or OTN channels with manually cross-connections at intermediate line terminating elements. In yet another exemplary embodiment, the present disclosure includes a tandem connection monitoring selection method across multiple operator domains.

Optical network in-band control plane signaling, virtualized channels, and tandem connection monitoring systems and methods

The present disclosure provides systems and methods for rapid circuit provisioning in Optical Transport Networks (OTN) using signaling and routing protocols thereby enabling fast mesh restoration. The present invention utilizes a shim layer between OTN messaging (e.g., GCC or High-Level Data Link Control (HDLC)) and the associated signaling and routing protocol (e.g., OSRP, GMPLS, etc.). If an ODUk Connection CTP or TTP needs to be created, the shim layer runs a fast 'OTN Setup' protocol, while buffering out going OTN messages. Incoming messages are still processed and do not require additional buffering. The purpose of the OTN Setup protocol is to allow the OTUk to re-frame on its client ODUk, while buffering out-going messages. When re-framing completes, buffers are released and the OTN messaging resumes without dropping any of the signaling frames.

Systems and methods for rapid optical transport network circuit provisioning

The present invention provides systems and methods for abstracting a network topology into virtual links and supporting both generic and instantiated virtualized links for linking a virtualized topology with actual resources within a domain, providing security over network topology information, providing control over the allocation of resources, and reducing the complexity of advertising.

System and method for supporting virtualized links at an exterior network-to-network interface

The present invention provides systems and methods to mix In-Band (IB) and Out-of-Band (OOB) signaling mechanisms under the Private Network-to-Network (PNNI) protocol for optical control plane connectivity. The present invention provides mechanisms for establishing and controlling OOB control plane communications. By default, the mechanisms treat all links as IB to discover nodes and links using IB mechanisms. For any blocked links, the link can be configured as OOB if there is a data communication network (DCN) connection to the remote node.

Systems and methods for private network-to-network interface out-of-band signaling and path blocking

Systems and methods for connections on an Automatically Switched Optical Network (ASON) network including an ASON database and path computation algorithm, mechanisms for Ethernet connections over ASON, and mechanisms for label negotiation for SNCs are provided. Advantageously, the present invention provides mechanisms for ASON path computation and virtual topology management, Ethernet connection establishment, modification, and deletion in ASON networks, and label negotiation without requiring binding and releasing of connections before label negotiation.

Growing community of inventors

Woodstock, GA, United States of America

Vagish Madrahalli