System for personalized information distribution

System for personalized information distribution (PID) from an information source server (1) to several user terminals (2) via an information distribution network (3) comprising several active nodes (4), forming a PID-tree (5). The active nodes comprise distribution control means (6) setting the information distribution process in the relevant active node in accordance with local distribution parameters (parm). The distribution parameters are manageable via said network by distribution control codes (dcc) originated by said user terminals or by other active nodes in the PID-tree. For setting-up or modifying the respective PID-path for the distribution of information from the information source server to the respective user terminal, the user terminal transmits its distribution control code to the first and—as far as necessary—further active nodes of the PID-path between the user terminal and the information source server and sets the active node's distribution control means according the user's capabilities and preferences.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a system for personalized information distribution (PID) from an information source server to several user terminals via an information distribution network.

The proposed PID service aims to provide tailor-made information distribution to receivers using different devices, access technologies and access speeds. Examples of PID services are live television in a user's own format/speed and language, real-time stock exchange information of your favorite stocks on various devices, or distribution of a video stream to many end-users with different access technologies, access speeds, and various requirements regarding QoS.

2. Description of the Prior Art

In current IP networks, it is difficult to distribute information, e.g., a video stream, to many end-users with different access technologies and access speeds. Some possible solutions are:sending multiple videostreams with different quality classes (e.g., 33 kbps on PSTN, 64 kbps on TSDN, 500 kbps on ADSL, etc.);sending the videostream with the lowest quality and decreasing the service f or the end-users connected with higher speeds;selective discard of information elements, e.g., low priority videoframes in hierarchically encoded schemes. These solutions can be implemented using traditional point-to-point IP, or using IP-multicasting. The former is resource-intensive, but mechanisms for quality differentiation exist; the latter is resource efficient, but the creation and management of large multicast is complex. Moreover, until now IP-multicast only supports best-effort.

SUMMARY OF THE INVENTION

According to the present invention an active solution for PID is proposed, applicable to video and or other content distribution. In this solution, content is generated by a (single) source in a single format/quality, and distributed through the network to the end-users using a PID-tree consisting of paths (branches) with “active nodes” (also called “active network nodes ” or “active (network) servers”) . The end-users may have different access capabilities like PSTN, ISDN, ADSL and LAN, and may have different terminal capabilities, for instance color or black/white display etc. or other Quality-of-Service parameters. The appropriate (not necessarily all) active nodes run “PID Active Components” (PACs) which function as distribution control (or processing) means which, inherently to the active node or active network technology, can be set and manipulated from outside the respective active node, via the network. The PACs can be set by user terminals and by each of the active nodes. In particular for the distribution of information via said PID-trees, the PACs may be composed of a specific configuration of replication (‘R’) and transcoding (‘T’), while additional Basic Building Blocks (EBB) may be added. Setup of the delivery tree, i.e., the PID-tree, is executed fully distributed and is governed by an advertise-subscribe model: content will be advertised using existing end-user mechanisms, e.g., via a webpage (of the relevant PID service provider), and end-users can subscribe to specific content. The “algorithm” for the setup or modification of the PID-tree will be discussed below.

Summarizing, the invention refers to a system for personalized information distribution (PID) from an information source server to several user terminals via an information distribution network, where, according to the invention, the network comprises several active nodes, the information being distributed to the terminals via a PID-tree comprising respective PID-paths between respective user terminals and the information source server, each PID-path comprising one or more of the active nodes, while the active nodes comprise distribution control means for setting the information distribution process in the relevant active node in accordance with local distribution parameters, the distribution parameters being manageable via the network by means of distribution control codes originated by the user terminals or by other active nodes. For setting-up or modifying the respective PID-path for the distribution of information from the information source server to the respective user terminal, according to a further elaboration of the invention, the user terminal transmits a subscription message, containing a distribution control code to the first active node of the PID-path between the user terminal and the information source server, the distribution control code representing the user terminal's capability parameters and/or the user's preferences parameters like QoS, bandwidth, screen mode etc. The control code, after being received by the first active node, is compared in the distribution control means with the local distribution parameters already set (if not explicitly set, the parameters may have default values) in the distribution control means, while the parameters are amended by the control codes in conformity with the user terminal's capability parameters and/or the user's preferences parameters if the local distribution parameters set in the active node do not match those user terminal's capability parameters and/or the user's preferences parameters. When they do match, it may be unnecessary to amend the distribution parameters in any of next upstream active nodes. When the set local parameters are amended, the next upstream active node has to be investigated to determine whether its local parameters do or do not match the user terminal's or user's parameters. According to the invention, in that case, insofar applicable with respect to the number of intermediate active nodes in the relevant PID-path, in one or more sequential steps, a further distribution control code (which may be equal to the control code already mentioned), representing the last active node's new local distribution parameters is always forwarded to the next intermediate active node in the relevant PID-path between the user terminal and the information source server, in which next intermediate active node its distribution parameters, set in its distribution control means, are compared, by those distribution control means, with the parameters as represented by the control code received from the preceding active node and are, if applicable, brought into conformity with the parameters represented by that control code. So, according to the above “algorithm”, the distribution parameters in each PID-branch used for downstream distribution of information from the information source to the users is set in an upstream process, initiated by the user terminal, which sends its desired distribution (transmission) parameters to the first, most downstream, active node in the distribution chain (PID-path), setting the node's distribution parameters (QoS, bandwidth etc.) as desired by the terminal, after which the most downstream node, aware of the PID-path, successively investigates its predecessor in the PID-path whether they are fit for downstream distribution the source server's information in accordance with the user (terminal)'s desires, represented by the upstream forwarded distribution control code.

DETAILED DESCRIPTION

FIG. 1, illustrating the present invention, shows an information source server1, distributing information to several user terminals2via an information distribution network3. The network3comprises several active nodes4, the information being distributed to the terminals2via a PID-tree5comprising respective PID-paths between the respective user terminals2and the information source server1. Each PID-path comprises one or more of the active nodes4; the active nodes comprise distribution control means6(“PAC” inFIG. 1a), the distribution parameters of which can be controlled via the network3by the user terminals2and mutually by the several active nodes.FIG. 1shows a PID-tree consisting of two active PID-paths,1-4f-4d-4a-2aand1-4f-4e-4c-2erespectively as the result of a (previous) subscription of an ADSL-user2aand an ISDN-user2eto the server's1information distribution service. This has led to the establishment of a replication building block (RBB) R1and transcoding building blocks (TBBs) T1and T2at active node4f(T1transcodes—resulting in bandwidth reduction—the downstream information stream to be fit for ADSL, T2in the same way for ISDN).

FIG. 1ashows schematically the function of the distribution control means6, also indicated as “PAC”, part of active nodes4. A distribution control code “dcc” is supplied to the PAC6after which the PAC compares the parameters as requested by the user and/or the user terminal2with the parameters (“parm”) as which are set in the active node at that moment. When the requested parameters differ from the locally set parameters, the local parameters will be brought into conformity with the requested parameters. Moreover, (a replica of the) distribution control code will be forwarded to the next active node in the PID-path towards the information source server1.

FIGS. 2 and 3show stepwise modifications to this PID-tree when adding users (activation of user terminals).FIG. 2illustrates the modifications when a PSTN-user2dis added to the PID-tree.

The relevant user terminal2dtransmits a distribution control code to the first active node of the PID-path between the user terminal and the information source server, viz, active node4c. The distribution control code dcc (FIG. 1a) represents the user terminal's capability parameters, viz. PSTN, and/or the user's preferences parameters, for instance a preferred use of low resolution video. The control code, after being received by the first active node4c, is compared in the distribution control means6(FIG. 1a) with the local distribution parameters parm (FIG. 1a) already set in the active node, viz, set to be fit for ISDN (terminal2e) . Now the parameters are amended by the control codes: (1) a replication building block R2is added and (2) a transcoding building block (TBB) T3is added, the latter being involved with reduction of the bandwidth from ISDN level—fit for terminal2e—to PSTN level, fit for terminal2d. While the PID-path between the terminal2dand the source server1comprises some more intermediate nodes, viz, the nodes4eand4f, in next step of the “set-up algorithm” a further distribution control code, representing the last active node's4cnew local distribution parameters, is forwarded to the next intermediate active node4ein the PID-path between the user terminal and the information source server1. In this intermediate active node4eits distribution parameters, set in its distribution control means are compared, by those distribution control means, with the parameters as represented by the control code received from the preceding active node4cand are brought into conformity with the parameters represented by the control code. In this case the distribution parameters do match the capability/preference parameters of ISDN terminal2eas well as PSTN terminal2d. For that reason the process is stopped, because the distribution parameters of active node4eare fit for terminals2dand2e. If the parameters would, however, not match the requested or desired terminal/user parameters, the process would be continued stepwise in one or more next steps, until the distribution parameters in the whole PID-branch match the requested terminal/user parameters.

FIG. 3illustrates the stepwise process according to the invention when a LAN-enabled terminal2crequests accession to the PID service. In the same way as described above, a distribution control code, representing the parameters fit for LAN terminal2cbandwidth, high video quality etc.) is sent to active node4b, which sets its distribution parameters —transmission bandwidth, Quality-of-Service, replication on/off, etc.—accordingly. A transcoding building block will not be necessary if LAN terminal2cis fit for the “full” output bandwidth of the source server1, while —as long as no additional terminals are actively connected to node4b—no replication building block is requested too. The distribution control code initiated by terminal2c—or a replica distribution control code, in each case a control code representing the terminal's and/or the user's requested capabilities and preferences—subsequently will be forwarded to active node4d. Comparing, in that node4d, the parameters set in the control means (PAC) of that node with the parameters as requested by the distribution control code, representing the LAN terminal2cand its user, will result in setting the parameters in node4dinto conformity with the requested parameters, including in this case the addition of a (new) replication BB, R3, to be involved with replicating the downstream information (packets) from the source towards ADSL terminal2aand LAN terminal2c. In a next step, under the control of the (replica of the) distribution control code, the parameters of node4fwill be brought into conformity with the (new) LAN terminal's2cspecifications and the already existing ADSL terminal's2aspecifications, resulting in a move of the transcoding BB T2involved with reduction from “full” bandwidth to ADSL bandwidth—from active node's4fPAC (control means) to the node's4dPAC. In other words, T2is removed from node4fand installed in node4d, enabling a “bandwidth split”: full bandwidth to LAN terminal2cand reduced bandwidth to ADSL terminal2a .