Alcatel Lucent

Alcatel

Tropic Networks Inc.

Bijan Raahemi

Bashar Said Bou-Diab

Fernando Cuervo

Jonathan Dean Segel

Kizito Gysbertus Antonius Van Asten

Sudhakar Ganti

Thomas George Zboril

Edward Aung Kyi Maung

Instead of implementing per flow measurement at every interface of every IGMP Router or Snooping Proxy in the aggregation network, as in the prior art 'per flow measurement' approaches, the present invention relates to a scheme where the IGMP Router or Snooping Proxy tracks the multicast subscription of each host (for IGMPv3) or subnet (for IGMPv1 and IGMPv2) and stores the information such as host id, the time the host joined a channel, the duration of the channel delivery, etc. in a database. This database (MIB) can then be pulled by a network management tool using SNMP or WSDM MUWS. According to the invention a mechanism for multicast host authorization is also provided.

Multicast host authorization tracking, and accounting

Priority-based access systems and methods for shared communication media are provided. The priority and a corresponding weight of traffic to be transmitted on a shared communication medium are determined. This determination may be made, for example, before a first attempt to transmit the traffic, or before a subsequent traffic transmission attempt following an unsuccessful transmission attempt. The weight controls a rate of change of an exponential delay range limit factor in proportion to a number of attempts to transmit the traffic. The resultant weighted delay range limit factor is used to determine a range of delays from which a delay is selected. A transmission back-off time is then determined based on the selected delay.

Access systems and methods for a shared communication medium

A system for providing resilient multimedia broadcasting services over a VPLS network is described. A Network Management System (NMS) calculates disjoint minimum cost trees using the Steiner algorithm, executed with extra steps to result in disjoint trees. Destination PE routers in the VPLS network are connected to the disjoint trees so that they can be serviced by either tree in case of a fault. Each of the disjoint trees is provisioned with enough bandwidth to carry all of the services provided by the VPLS network. Under normal operation, however, the services are distributed evenly over the trees. In the event of a fault, the services on a faulty tree are switched to another tree using split horizon bridging. Each Steiner tree can also be realized using point-to-multipoint LSPs which is fully protected by a precomputed point-to-multipoint LSP.

Resiliency in minimum cost tree-based VPLS architecture

Error correction on high speed interconnection links&#x2014;backplane or extended wires (cable, optical fiber)&#x2014;is exhaustively considered by many telecommunication vendors, especially those who offer 'scalable router' products. Since the 64b/66b encoding scheme is a strong candidate of high speed interconnection protocol, error correction on 64b/66b encoded links is of interest. Although the IEEE 802.3 10G Ethernet standard does not specifically refer to packet loss, it can be shown that even only a single-bit error correction can significantly enhance the quality of the link. The present invention presents a simple and fast error-correction scheme that can be used in conjunction with the 64b/66b encoding in products where intra-board (chip-to-chip) or inter-shelf interconnections of high speed elements are required. It utilizes the CRC16 to optimize on error detection, correction, or both: it detects and corrects all single-bit errors and detects all multiple-bit errors.

Error correction on M-bit encoded links

64/66b encoding (IEEE 802.3ae Standard for 10 Gigabit Ethernet) is based on a self-synchronous scrambler which inherently duplicates errors occurring in the transmission line. An error carryover indicator ECI vector is used to correct duplicated errors crossing the codeword boundary and entering into the next codeword. The ECI vector is updated for each codeword C(i) to provide the position of the erroneous bit(s) carried over to the next codeword C(i+1). The codeword C(i+1) is corrected by XOR-ing it with the ECI vector.

Accounting for error carryover in error correction on M-bit encoded links

A method for transmission of digital data in a form of data packets through links carrying data packets with error correction, includes the steps of enveloping a sent packet data, first with an error detection scheme, and secondly with an error correction scheme. The error correction applies to both the sent packet data and to the error detection field. If an error in either of these fields occurs, the error correction scheme attempts to correct it. Error correction may fail in which case the packet is dropped. If error correction does not fail, there is still a possibility that there was an error which error correction did not correct correctly, or did not detect at all because the power of the correction scheme was exceeded. In these cases, the error detection scheme provides a method or means to detect such errors and drop the packet. Corresponding interconnect system with error correction, encode and decode for such are also provided.

Growing community of inventors

Ottawa, Canada

Bijan Raahemi