摘要:
Disclosed herein is a connection bandwidth management process and system for use in a high speed packet switching network. The network comprises a plurality of switching nodes interconnected through a plurality of communication links. Each of the switching nodes comprises means for switching packets from at least one input link to at least one output link. Each of the output links are coupled to at least one buffer in the switching node for queuing packets before they are transmitted over the output link. Each of the communication links supports the traffic of a plurality of user connections statistically multiplexed over the link. Each user connection is allocated an initial agreed-upon bandwidth through the network, with each of the communication links being possibly oversubscribed.
摘要:
A method for establishing a network connection through a link issuing from a physical port is disclosed. The link has an aggregation of connections. The network connection has a required capacity. The method first computes, from mean bit rates of the aggregation of connections, a mean aggregate bit rate over the aggregation of connections. The method secondly computes, from burst durations from the aggregation of connections, a mean aggregate burst duration over the aggregation of connections. The method thirdly computes an equivalent capacity required on the link by the aggregation of connections, the equivalent capacity being a function of the mean aggregate bit rate and the mean aggregate burst duration. The method fourthly computes an aggregate equivalent capacity, the aggregate equivalent capacity being a function of the equivalent capacity and the required capacity of the connection. The method fifthly computes a bandwidth that would be reserved on the link after establishing the connection, the bandwidth being a minimum of a Gaussian approximation and the aggregate equivalent capacity. Then the network connection is established if the bandwidth is less than or equal to a total capacity for the link.
摘要:
A method and system for optimizing transmission links bandwidth utilization in an Asynchronous Transfer Mode (ATM) packet switching network including switching nodes interconnected by high speed transmission links, said network being made to transport user data traffic including PTM traffic organized into variable length packets, each packet comprising a variable length data payload and an original fixed length PTM packet header. The original PTM header is converted into an ATM-like header including a flag (F) identifying the packet as being a PTM packet, a label indication made to orient the currently-considered PTM packet within the ATM network nodes, a count (CNT) field for storing the PTM payload length indication therein to enable locating the PTM payload end position and a Header Error Control (HEC) field for storing an ATM-like error control byte (HEC) therein, which enables transporting the PTM packets over the ATM network links without having to chop the PTM payload into predefined fixed length segments by adding dummy bits to the last segment if required.
摘要:
A system for coding voice signal to optimize bandwidth occupation in a High Speed Packet Switching network while ensuring best voice transmission quality.The voice signal is first encoded using a conventional GSM like RPE/LTP coder providing first sub-frames of coded signal and tagging these first sub-frames as being non-discardable. In addition, a convenient difference between an RPE/LTP provided signal and a corresponding synthesized image is performed (see 36) and is also block encoded into second sub-frames which second sub-frames are tagged as being discardable sub-frames. Said second sub-frames when concatenated to corresponding first sub-frames provide so-called multirate frames. Then, when transmitting said multirate frames over the High Speed packet switching network, dropping discardable tagged data enables solution network congestion situations in any network node and at random with no significant disturbing effect over the voice communication operation.
摘要:
An apparatus and method for multicasting messages stored in data buffers of a data storage. Each message is composed of data stored in a plurality of the data buffers. Each data buffer is controlled and mapped to a unique direct control block (DCB) which stores information characterizing the data buffer. By chaining the DCBs variable length, messages can be generated. Indirect control blocks (ICB) stores information characterizing the data or messages duplicated and points to a DCB. A field in the DCB carries a count representing the number of times the message is to be duplicated.
摘要:
A system adapts access to a packet switching network. A dynamic bandwidth adaptation continuously monitors the mean bit rate of a signal source and the loss probability of a connection in the network. A filtering means removes noise from the mean bit rate and loss probabilty. A test means determine whether the values fall within a pre-defined acceptable adaptation region in a mean bit rate, loss probability plane. Triggering means initiate bandwidth adaptation procedures when the values fall outside of the region which in turn, initiate means for acquiring a new connection bandwidth, and determining new parameters for the adaptation mechanism.
摘要:
A method and an apparatus for reducing the jitter and end-to-end delay on lines of a packet switching network conveying voice or video digitalized data for one or more connections between a local source and a remote source at a constant bit rate.The method and apparatus of the invention are for use in a voice or video processor of a voice or video processing server of a network node; the method and the apparatus provide a way of controlling the remote traffic rate from the remote source before accessing the processor without using an external clocking such as the network clock.The solution proposed by the invention consists in buffering the remote and local traffics to adapt the remote traffic rate to the local traffic rate, which is supposed having a limited jitter, while sequencing of the access of the buffered data to the processor.
摘要:
An improved access control system for a memory system in which memory locations can be allocated to virtual output queues dedicated to output ports from the system. The virtual queues can be used to handle data of different priorities. Thresholds are defined for the occupancy of the overall memory and of each virtual queue. The access control system regulates the acceptance of data stored in input adapters by determining whether a back pressure situation exists for the data's target output adapter for the class of traffic to which the data belongs. A single-bit access-controlling back pressure signal is generated as a function of the occupancy level of either the overall memory or of the virtual queue defined for the target output adapter.
摘要:
Method and system for adapting access to a packet switching network including a dynamic bandwidth adjustment mechanism which continuously monitors the mean bit rate of the signal source and the loss probability of the connection. These values are filtered to remove noise and then used to test whether the values fall within a pre-defined acceptable adaptation region in the mean bit rate, loss probability plane. Values falling outside of this region trigger bandwidth adaptation procedures which, in turn, result in acquiring a new connection bandwidth, and determining new parameters for the adaptation mechanism. Furthermore, the mechanism controls the number of connections that can be adapted by a single processor, given its processing capability. It ensures fairness between the connections in the sense that it prevents a single connection from using, on the average, a greater portion of the processor capacity than it should.
摘要:
Traffic congestion control is provided for a network node multiport switch capable of switching data packets of different priorities from input lines, via receive adapters, to output lines via transmit adapters. A spacing function is performed to limit the rate of data transfers through the switch in the absence of high priority data at the input lines and in the absence of a backpressure signal indicating the switch is congested at its output. If high priority data is detected or a backpressure signal has been generated, the data transfer rate is increased to deal with possible congestion.