Abstract: According to the present invention, a technique for delivering content over a network having endpoints and nodes that store content is provided. In one embodiment, the technique is realized by first launching a request for content from a requesting end point. Then propagating the request over the network to the nodes. While the request propagates, it leaves a trail at the nodes and, when content matching the request is located, a copy of the content is returned to the requesting endpoint over the trail left by the request.

Abstract: A method and apparatus for controlling congestion at a node in a data network. The node includes an input for receiving traffic units from the network, an output for releasing traffic units to the network and a control unit. The control unit is responsible for estimating a level of data occupancy of at least a portion of the network by looking at the traffic units received at the input from a remote node in the network. When the data occupancy level reaches a certain threshold, the node issues a control signal to the remote node such that the remote node lowers its rate of traffic units input in the network. By estimating the network data occupancy level, congestion at the node can be effectively foreseen and controlled.

Abstract: According to the present invention, a technique for delivering content over a network having endpoints and nodes that store content is provided. In one embodiment, the technique is realized by first launching a request for content from a requesting end point. Then propagating the request over the network to the nodes. While the request propagates, it leaves a trail at the nodes and, when content matching the request is located, a copy of the content is returned to the requesting endpoint over the trail left by the request.

Abstract: The present invention relates to a lossy switch for processing data units, for example IP data packets. The switch can be implemented as a contained network that includes a plurality of input ports, a plurality of output ports and a lossy switch fabric capable of establishing logical pathways to interconnect a certain input port with a certain output port. A characterizing element of the switch is its ability to control the discard of data packets at a transport point within the switch. This control mechanism prevents and reduces congestion which may occur within the switch fabric and at the level of the input and output ports. The system also supports priorities, routing HI priority request data packets over the switch fabric before LO priority request data packets, and discarding LO priority data packets first when controlling congestion.