Nortel Networks Corporation

Ciena Corporation

Ciena Luxembourg S.a.r.l.

Chris Ramsden

Marc Holness

Simon P Parry

Bashar Abdullah

Martin Soukup

Craig Warren Parker

Sharon Chisholm

Marc-Andre Rochon

Philip Christian

April Pennisi

Colin Murgatroyd

Walter Collins

James Alves

Charles Gale

Doug Trump

Simon Parry

A system for controlling packet forwarding through a point-to-point (p2p) connection between first and second end nodes of a packet network domain having a mesh topology. The system comprises a sub-ring network instantiated in the network domain, the sub-ring network comprising a pair of topologically diverse ring spans extending between the first and second end nodes. Each of the end nodes is controlled to forward packets of the p2p connection through the sub-ring network in accordance with a ring network routing scheme, and an intermediate node traversed by one of the ring spans is controlled to forward packets of the p2p connection through the ring span in accordance with a linear path routing scheme.

Linear route protection

A method and network for adapting a network management protocol (e.g., TL-1) for various transmission protocol terminologies (e.g., SDH and SONET). A network element operates in one transmission protocol mode and sends network management messages to a network management device in a managing terminology based on another transmission protocol mode. The network management device then translates the network management messages to be presented in a user interface at the network management device to an operating terminology based on the operating transmission protocol mode used by the network element.

Method and network for adapting a transaction language for network elements

A method of performance monitoring and a processor for performance monitoring in a communications network are provided. A signal is monitored over time by allocating a current signal quality characterization to the signal, selected from at least two such signal quality characterizations, such as perfect time, errored time and unavailable time. A plurality of time intervals making up a continuous succession of such time intervals are identified, such that a current time interval is terminated and a next time interval is initiated each time the signal quality characterization allocated to the signal changes. Then, a record of each identified time interval is generated and can be used to generate a performance log. Selected records may be manipulated to reduce the amount of memory required to store the records while intelligently degrading their accuracy.

Performance monitoring in a communications network

Data for inclusion in a probable cause field of a telecommunications network alarm indication message is structured to comprise first and second delimited data elements respectively indicating first and second predetermined (ie standardized) probable cause codes, the first and second predetermined probable cause codes relating to one or more characteristics of an event occurring or having occurred in a telecommunications network. Methods, apparatus and computer programs for generating and for processing such data is provided as well as signals representing such data.

Probable cause fields in telecommunications network alarm indication messages

To provide a graphic user interface, supported by HTML or Java script, to a personal computer () for the control of SONET/SDH network elements (), an RS-232 port of a PC is used to establish a PPP session to a remote access server, RAS (). The network element () is therefore configured to imitate a modem, and to route PPP packets into its related management system across an optical ring (). The management system may include an intermediate network manager () and a DHCP server (). Once legitimacy of the PC is established through the IP session, the PC is provided with an IP address to invoke the PC's IP stack. Subsequently, IP is communicated across the PPP session, with the RAS () configured to terminate the PPP session and forward IP packets into an IP network (). IP packets (), received at a web server (), are converted into command line interface (CLI) messagesand are sent directly to the network manager () within an IP packet. The network manager () terminated the IP packet and re-packages the CLI messages into an optical carrier format () for relay to an addressed network element (). The addressed network element (), which is responsive to the CLI messages from a management perspective, then alters its set-up or functionality accordingly. Complex text-based CLI instructions are thus avoided by a field-based engineer through the use of a GUI supported by a PC having web-browser capabilities, with an typical architecture shown in FIG.

Optical communication network and method of remotely managing multiplexers

Growing community of inventors

Hertford, United Kingdom

Chris Ramsden