Patents by Inventor Dinesh Mohan

Dinesh Mohan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20070268817
    Abstract: A method and system for protecting a service available on a broadcast domain. A sub-domain is established within the broadcast domain. The sub-domain includes a group of nodes used to provide a communication path to the service. A primary sub-domain maintenance association and a back-up sub-domain maintenance association are monitored. The primary and sub-domain maintenance associations are a set of primary and back-up paths, respectively, representing connectivity between nodes acting as edge nodes in the sub-domain. A fault is detected within the primary sub-domain maintenance association and a switch to the back-up sub-domain maintenance association occurs.
    Type: Application
    Filed: October 11, 2006
    Publication date: November 22, 2007
    Inventors: Gerald Smallegange, Dinesh Mohan, Marc Holness, Martin Charbonneau, Donald Ellis, Adrian Bashford
  • Patent number: 7249169
    Abstract: A multi-stratum multi-timescale control for self-governing networks provides automatic adaptation to temporal and spatial traffic changes and to network state changes. Microsecond timescale reacting through the routing function, a facet of the lowest stratum, allows a source node to choose the best available route from a sorted list of routes, and to collect information on the state of these routes. Millisecond timescale correcting through the resource allocation function, a facet of the intermediate stratum, allows the network to correct resource allocations based on requirements calculated by the routing function. Long-term provisioning through the provisioning function at the higher stratum allows the network to recommend resource augmentations, based on requirements reported by the resource allocation function. The control is implemented in the network through coordination across edge node controllers, core node controllers, and network controllers.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: July 24, 2007
    Assignee: Nortel Networks Limited
    Inventors: Francois J Blouin, Dinesh Mohan, Maged E Beshai
  • Publication number: 20070116045
    Abstract: Frames of customer traffic may be encapsulated by adding Mac-in-Mac (MiM) encapsulation fields for transportation of the frames over a portion of provider network. The MiM encapsulated traffic may be further encapsulated using VPLS by adding VPLS encapsulation fields for transportation of the frames over another portion of the provider network. The MiM encapsulations use provider network_MAC addresses which enables VPLS MAC learning to occur using provider network MAC address space. MiM tunnels are mapped to VPLS service instances which are assigned pseudowire tags for transportation over the VPLS portion of provider network. The MiM header is retained when the MiM encapsulated frames are transported over the VPLS portion of the provider network. As VPLS frames exit the core network, the VPLS encapsulation fields are removed to extract the original MiM encapsulated frames for further transportation over the MiM portion of the provider network.
    Type: Application
    Filed: September 30, 2006
    Publication date: May 24, 2007
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Hamid Brahim
  • Patent number: 7152115
    Abstract: A network can be organized for providing virtual private network services to customers into two regions. A network core for providing layer 2 transport and an associated number of logical provider edges. Each logical provider edge is partitioned into first and second portions. The first portion provides virtual private network services to customers. The second portion works with the core network to communicate with any other logical provider edge within the network. The first portion designated as the PE-Edge includes a group of functions such as a function for configuring optical Ethernet layer 2 virtual private network service, a function for service labeling, a function for ingress traffic management, and a function for information exchange between local VPN and core VPN.
    Type: Grant
    Filed: July 9, 2002
    Date of Patent: December 19, 2006
    Assignee: Nortel Networks Limited
    Inventors: Hamid H. Ould Brahim, Dinesh Mohan, Vasile Radoaca, Michael Chen
  • Publication number: 20060092847
    Abstract: Maintenance entities may be defined between customer and provider flow points to allow performance management to take place on an Ethernet network. The maintenance entities may be defined for access link, intra-domain, and inter-domain, and may be defined on a link or service basis. Performance parameters, including availability metrics, may be collected for the maintenance entities. The provision of such availability metrics in an Ethernet based solution to facilitate consistency of service management and operations for carriers transitioning to the Ethernet solution.
    Type: Application
    Filed: December 15, 2005
    Publication date: May 4, 2006
    Inventor: Dinesh Mohan
  • Publication number: 20060031482
    Abstract: Connectivity fault notification is provided by generating an alarm indication signal at a device that is logically adjacent to the fault, and forwarding the alarm indication signal upward through various levels to at least one client level entity. The alarm indication signal may be suppressed at any level for a service instance if service is restored at that level, or if a protection path prevents disruption of the service instance at that level, or auto-suppressed at an originating node based on number of times transmitted or elapsed time. The alarm indication signal may include a point of failure indicator such as the MAC address of the device that generates the alarm indication signal, or a failed resource identity such as an IEEE 802.1AB LLDP MAC Service Access Point (“MSAP”). Further, the alarm indication signal may be employed to trigger use of the protection path.
    Type: Application
    Filed: May 25, 2005
    Publication date: February 9, 2006
    Inventors: Dinesh Mohan, Marc Holness
  • Publication number: 20060002370
    Abstract: The two types of virtual local area networks (VLANs) may be defined: p-bits-Inferred-scheduling class VLAN (p-VLAN); and VLAN-ID-Only-Inferred-scheduling class VLANs (v-VLAN). As such, upon receipt of an Ethernet frame, the type of VLAN associated with the Ethernet frame may be determined. The type of VLAN provides the receiving node with an indication of a method of determining a scheduling class. A p-VLAN supports multiple scheduling classes. For a p-VLAN, the scheduling class and drop precedence for the received Ethernet frame may be determined based on a “service map” that describes the relationship between the p-bits and forwarding treatment. A v-VLAN supports a single scheduling class. As such, the scheduling class for a received Ethernet frame may be determined based on the VLAN-ID of the received Ethernet frame. The described VLAN QoS information may be configured or signaled across the network.
    Type: Application
    Filed: June 30, 2005
    Publication date: January 5, 2006
    Inventors: Sameh Rabie, Osama Aboul-Magd, Dinesh Mohan
  • Publication number: 20050099954
    Abstract: Network topography may be discovered by a network element on an Ethernet network by collecting connectivity check messages periodically issued by other network elements on the network and using the information gleaned from those messages to build a topography database. Since the connectivity check messages may be link level or service instance based, the topography database may include network topography as well as service topography on the Ethernet network. Ethernet OAM loopback frames may also be used to cause network elements on the Ethernet network to issue response frames directed to the initiating network element. By collecting responses from the responding network elements, the initiating network element can build a topography database of network elements on the Ethernet network. This topography database may show the overall network topography or service instances on the network, and may provide visibility within one or more domains.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 12, 2005
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Timothy Mancour, Marc Holness
  • Publication number: 20050099952
    Abstract: Maintenance entities may be defined between customer and provider flow points to allow performance management to take place on an Ethernet network. The maintenance entities may be defined for access link, intra-domain, and inter-domain, and may be defined on a link or service basis. The maintenance entities may be used to monitor performance within a network or across networks, and may be used to monitor various performance parameters, such as frame loss, frame delay, frame delay variation, availability, errored frame seconds, service status, frame throughput, the number of frames transmitted, received or dropped, the status of a loopback interface, the amount of time a service has been unavailable, and many other parameters. Several management mechanisms may be used, and the measurements may be collected using a solicited collection method, in which a responses are required and collected, or an unsolicited collection method in which a response is not required.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 12, 2005
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Marc Holness
  • Publication number: 20050099955
    Abstract: Ethernet OAM may be used to trace a path on an Ethernet network. If the path reaches the destination, there is no fault. If the path doesn't reach the destination, the network element farthest along the path is adjacent the fault. The path trace may be used from both ends of a given path to confirm the presence of a single fault or to determine the likelihood of multiple faults on the path. A path trace Ethernet OAM frame may be issued on the network with instructions that network elements with knowledge of a destination address should respond. If a network element knows the destination address, the receiving network element responds to the initiating network element with a unicast OAM frame and forwards the OAM frame if possible. The sequence of unicast response frames allows the initiating network element to build a path through the network toward the destination element and identify where the path stops.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 12, 2005
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Timothy Mancour, Marc Holness
  • Publication number: 20050099951
    Abstract: Ethernet OAM connectivity check may be used to detect connectivity failures across a given pair of network elements on an Ethernet network. Connectivity check frames are generated and sent to a specific unicast DA or to a multicast DA. Once a network element begins to receive connectivity check frames, it expects to continue to receive further periodic connectivity check frames from that network element. If the network element stops receiving periodic connectivity check frames, it detects that connectivity to the sending network element is broken. Once a fault is identified, the fault may be verified using a loopback function, which causes a network element receiving an Ethernet frame to transmit a corresponding frame back to the original network element. Loopback may be intrusive such that all received frames are looped back except OAM frames, or non-intrusive where only OAM frames are looped back.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 12, 2005
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Timothy Mancour, Marc Holness
  • Publication number: 20050099949
    Abstract: Ethernet OAM domains may be defined by defining reference points on the Ethernet network and using the reference points to insert and extract Ethernet OAM flows. The reference points may be network elements at the edge of a provider's domain, customer elements, or network elements configured to perform OAM flow handoffs between domains. By defining OAM multicast addresses and OAM flow identifiers, and allowing the reference points to be addressed by the multicast address and filtering to be performed by the reference points based on the OAM flow identifiers, OAM flows may be defined on the network. For example, customer-customer OAM flows may be defined, intra-provider and inter-provider OAM flows may be defined, and various segment OAM flows may be defined. An OAM frame format is provided to enable the OAM flows to be carried in a conventional Ethernet network.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 12, 2005
    Applicant: Nortel Networks Limited
    Inventors: Dinesh Mohan, Timothy Mancour, Marc Holness
  • Publication number: 20030126246
    Abstract: A multi-stratum multi-timescale control for self-governing networks provides automatic adaptation to temporal and spatial traffic changes and to network state changes. Microsecond timescale reacting through the routing function, a facet of the lowest stratum, allows a source node to choose the best available route from a sorted list of routes, and to collect information on the state of these routes. Millisecond timescale correcting through the resource allocation function, a facet of the intermediate stratum, allows the network to correct resource allocations based on requirements calculated by the routing function. Long-term provisioning through the provisioning function at the higher stratum allows the network to recommend resource augmentations, based on requirements reported by the resource allocation function. The control is implemented in the network through coordination across edge node controllers, core node controllers, and network controllers.
    Type: Application
    Filed: December 28, 2001
    Publication date: July 3, 2003
    Inventors: Francois J. Blouin, Dinesh Mohan, Maged E. Beshai
  • Publication number: 20030018820
    Abstract: A network can be organized for providing virtual private network services to customers into two regions. A network core for providing layer 2 transport and an associated number of logical provider edges. Each logical provider edge is partitioned into first and second portions. The first portion provides virtual private network services to customers. The second portion works with the core network to communicate with any other logical provider edge within the network. The first portion designated as the PE-Edge includes a group of functions such as a function for configuring optical Ethernet layer 2 virtual private network service, a function for service labeling, a function for ingress traffic management, and a function for information exchange between local VPN and core VPN.
    Type: Application
    Filed: July 9, 2002
    Publication date: January 23, 2003
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: Hamid Ould-Brahim, Vasile Radoaca, Dinesh Mohan, Michael Chen