Abstract: A network switch as well as methods, systems and computer program products for controlling congestion at a granularity of less than a link are provided. Such finer granularity may be provided by pausing traffic at a source port level of a network switch. The network switch which transmitted a message which resulted in congestion being detected is notified of the congestion and pauses the communications from the source port of the message while maintaining communications over the link from other source ports. Such source port level congestion control may be provided by a network switch having a sub-queue of its output queues where each sub-queue corresponds to an input port. Source port level pausing of transmissions may then be provided by pausing the sub-queue associated with a source port.

Abstract: Described is a scalable interface including a plurality of 2-bit transmission channels. An encoder partitions a digital bit stream into 3 bits which are coded into 4 bits with each pair of bits in each 4 bit pattern transmitted via back-to-back clock cycles on separate ones of the channels.

Abstract: Methods, systems and computer program products are provided for which associate physical links of a network device to aggregator ports of the network device where there are more physical links of the network device capable of aggregation than aggregator ports of the network device. Physical links are associated with the aggregator ports of the network device based on a session invariant characteristic of the physical links until either all of the aggregator ports of the network device have been associated with physical links or all of the physical links capable of aggregation have been associated with an aggregator port. The remaining physical links are then utilized as single links to the network device irrespective of the physical link's capability to aggregate.

Abstract: Described is a scalable interface including a plurality of 2-bit transmission channels. An encoder partitions a digital bit stream into 3 bits which are coded into 4 bits with each pair of bits in each 4 bit pattern transmitted via back-to-back clock cycles on separate ones of the channels.

Abstract: In pause time based flow control systems having station-level granularity, a station or switch may detect congestion or incipient congestion and send a flow control frame to an upstream station, commanding that upstream station to temporarily stop (pause) sending data for a period of time specified in the flow control frame. The traffic pause gives the downstream station time to empty its buffers of at least some of the excess traffic it has been receiving. Since each downstream station operates independently in generating flow control frames, it is possible for the same upstream station to receive multiple, overlapping pause commands. If an upstream station which is already paused receives subsequent flow control frames from the same downstream station that triggered the pause, the upstream station's pause timer is rewritten using the pause times in the successive flow control frames.

Abstract: A 2-bit communication channel is made to transmit complex data patterns by partitioning a digital string into 3-bit binary patterns which are encoded into 4 bits binary pattern and transmitted over the 2-bit communication channel in pairs using adjacent clock cycles on the 2-bit channel. Pre-defined ones of the 4-bit encoded data structures are used for framing on the channel and cannot be used to transmit data.

Abstract: When multi-destination traffic is distributed through a host or switch, the decision to distribute each frame is performed by each egress port and not the ingress port. Within a link aggregation group, the multi-destination frame is sent to each of the egress ports within the link aggregation group. Each of such ports will then determine whether it should re-transmit the frame. If not, the frame is discarded.

Abstract: A data processing system and method in a computer network are disclosed for improving performance of a link aggregation system included in the network. Parameters are established which are utilized to determine performance criteria of the link aggregation system. A performance of the link aggregation system is determined by determining the performance criteria. The performance of the link aggregation system changes in response to a flow traffic burden on the link aggregation system changing. The link aggregation system dynamically modifies the parameters in response to the changing performance of the link aggregation system. The link aggregation system is self-tuning and capable of automatically adjusting to a changing flow traffic burden on the link aggregation system.

Abstract: Components of an Ethernet communication system are placed in low power modes when such low power modes are feasible and permitted. The auto-negotiation next page feature of the Ethernet standard is utilized to exchange signals indicating that both ends of the system are capable of a low power mode. If capable and conditions for low system power usage permit, then the auto-negotiation feature is used to signal the eligibility of both ends of the system to enter a low power mode at which time the low power mode is activated. The system remains in the low power mode until data is to be transmitted.

Abstract: A 2-bit communication channel is made to transmit complex data patterns by partitioning a digital string into 3-bit binary patterns which are encoded into 4 bits binary pattern and transmitted over the 2-bit communication channel in pairs using adjacent clock cycles on the 2-bit channel. Pre-defined ones of the 4-bit encoded data structures are used for framing on the channel and cannot be used to transmit data.

Abstract: An improved method and apparatus are provided for queuing and triggering the flow of data across ATM networks. A connection is established between an insertion server and a client multiplexer. The insertion server prepares a timing response and establishes a transmit queue threshold for a pending trigger point for inserting data. The insertion server enqueues data. Responsive to receiving a timing request from the client multiplexer, the insertion server sends the timing response. Responsive to receiving a stream request from the client multiplexer, the insertion server transfers the enqueued data. The client multiplexer includes a timer for identifying an offset time between sending the timing request and receiving a timing response from the insertion server. The client multiplexer uses the offset time to set a count down timer for sending the stream request. The client multiplexer processes the data transferred by the insertion server and optionally sends a stop stream command to the insertion server.

Abstract: An improvement in the Open Systems Interconnection model in which Service Access Points can be established directly between peer entities in the same layer of a protocol stack. This direct seamless peer-to-peer communication is vastly superior to the use of a higher level relay function to set up and manage the communication path. In particular, setup messages are exchanged between the peer entities and a higher layer to create the Service Access Point between the peer entities. The setup and management capabilities are contained in each of the peer entities and hence no relay function is required after the peer Service Access Point, substantially speeding up the communication and reducing the management overhead.

Abstract: Method and apparatus are provided for segmenting a multiple program multimedia digital data stream for transmission over a distribution communications network. Each program multimedia digital data stream includes sequential transport system (TS) packets with program clock references (PCRs) at a set time interval and a program identification (PID) associated with the PCRs. The multiple program multimedia digital data stream is received. The TS packets are decoded to identify the program clock references (PCRs). A selected number N of TS packets are identified. The multimedia digital data stream into frames responsive to both the identified number N of TS packets and the identified PCRs. A program identification (PID) associated with one of the PCRs is selected for timing the transmission of segmented multiple program multimedia digital data stream.