Abstract: A data transmitter 10 transmits packets each with a sequence number and a priority added. A data receiver 20 detects any packet loss by referring to the sequence numbers added to the packets, and if detecting any packet of high priority as having been lost, requests for packet retransmission. Based on information about thus detected packet loss, the data receiver 20 generates and transmits an RR packet 110 indicating the packet reception state. The data transmitter 10 extracts from the RR packet 110 a packet loss ratio 200, and therewith, changes manners of priority assignment. The manners are so changed that the packet of high priority is found with a lower ratio when the packet loss ratio 200 is high, and when the packet loss ratio 200 is low, found with a higher ratio.

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The technique effects survivability and security of the optical networks by encompassing conventional electronic security with an optical security layer by generating replicated versions of the input data payload at the input node, and the transmission of each of the replicated versions over a corresponding one of the plurality of links. Moreover, each of the links is composed of multiple wavelengths to propagate optical signals or optical packets, and each of the replicated versions of the data payload may be propagated over a selected one of the wavelengths in each corresponding one of the plurality of links.

Abstract: A method for controlling data transmission over a network includes receiving a succession of data packets from a packet input at a potentially variable input rate, each packet in the succession potentially having a respective, non-uniform packet size. For each of the packets in the succession, the respective packet size is compared to a transmission credit allocated to the input. If the allocated credit is sufficient, compared to the respective packet size, the packet is transmitted over the network at a peak transmission rate predetermined by the network. If the allocated credit is insufficient, compared to the respective size, at least a portion of the packet is transmitted over the network at a rate no greater than a sustainable transmission rate predetermined by the network, which sustainable transmission rate is less than the peak transmission rate.

Abstract: A transmission method and apparatus for detecting the format of data when data is absent from the transmission packets. In situations where data to be transmitted via a predetermined network (e.g., IEEE 1394) is absent (i.e., missing, incomplete, intentionally blank, or not ready to be transmitted), the transmission method allows for the format of the absent data to be determined by the receiving side. According to this transmission method, the data transmission packets include a label section that indicates the format of the data or the absence of data. When the label section indicates an absence of data, a label group section is included in the data transmission packet to indicate the format of the data which is absent. This allows the receiving side to determine the format of the data that it should be receiving.

Abstract: A system and method for assembling multiple multicast data packets into a multicast burst according to multiple multicast burstification classes and switching the multicast burst through an optical burst switched network. To switch multicast data packets through an optical burst switched network according to the present invention, multicast data packets are first assembled into a multicast burst at an electronic ingress edge router according to a plurality of multicast burstification classes. The multicast burst is then switched through the optical burst-switched network to the destined electronic egress edge routers, disassembled back into multicast data packets and transmitted to multiple destinations.

Abstract: Each node (130) of a SONET bidirectional line switch ring (BLSR)(120) generates a squelch table. Squelch table generation does not require a separate computer connected to the node. Each node also generates a payload table indicating a type of a synchronous transport signals (STS) on each link (140) in the ring. The payload table allows each node to quickly determine the STS type on the protection channels when a ring switch occurs.

Abstract: Providing different levels of quality of service for different data flows being transported over a data link requires a very fast way to schedule individual packets for forwarding on the data link. The invention provides scheduling methods which give preference to higher priority packets while treating lower priority packets fairly. The methods can provide shorter latencies for higher priority packets than can many prior scheduling methods. The methods and apparatus of the invention are readily adaptable for use with scheduling rules provided in the form of hierarchical policy trees.

Abstract: A system, device, and method for transitioning from DVMRP to BGMP for interdomain multicast routing over the Internet multicast backbone (Mbone) switches the Mbone DVMRP distribution tree, piece by piece, into BGMP distribution trees. Each piece is a contiguous BGMP regional tree. The routers in the regional BGMP tree run an extended BGMP protocol. The root of the regional BGMP tree also runs DVMRP, and joins the Mbone DVMRP distribution tree in order to receive multicast packets and forward the multicast packets over the regional BGMP tree. The extended BGMP protocol ensures that no fowarding loops are created between the Mbone DVMRP distribution tree and the regional BGMP tree.