Push network

Details Push network Push network

2000-01-24

2004-06-29

Vincent, David (Department: 2661)

Multiplex communications

Pathfinding or routing

Switching a message which includes an address header

C370S432000

Reexamination Certificate

active

06757283

ABSTRACT:

CROSS REFERENCE TO RELATED APPLICATIONS
The present invention claims priority from Japanese Patent Applications No.11-015872 filed Jan. 25, 1999, No.11-015877 filed Jan. 25, 1999, No.11-096940 filed Apr. 2, 1999, No.11-096945 filed Apr. 2, 1999 and No.11-098101 filed Apr. 5, 1999, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention can be utilized for a push service which copies and distributes content to a plurality of destinations. In this specification, “push service” signifies a service which copies and distributes, to a plurality of user terminals, a packet sent by an information providing terminal, wherein the information providing terminal can transfer packets at a regular interval or at a prescribed time without knowing the state of the user terminals. Users can operate the user terminals whenever they wish and can extract the information that has been distributed.
2. Description of Related Art
FIGS. 44
,
45
and
46
serve to explain the configuration of a conventional datagram network, indicating respectively the configuration of a conventional packet, a conventional network and a conventional multicast packet. The network shown in
FIG. 45
has router
30
which has routing table
20
, and when a packet with address DA as shown in
FIG. 44
is sent into the network from a source, router
30
passes this packet if the address in question is downstream of the router.
There is only one such address in the network and if it is desired to send the packet to a plurality of addresses, a plurality of copies of the packet are formed as indicated in
FIG. 46
, and these are sent within the network after respective addresses have been added (DA
1
, DA
4
, . . . , DA
7
).
It is anticipated that future multimedia networks will see an increase in push services and that this will be accompanied by an increase in traffic comprising packets being multicast to a plurality of destinations. Networks of the sort described hitherto will not be able to deal with this situation efficiently. Push services have recently been increasing on the Internet as well, and content ranging from weather forecasts to the latest technical news is now being automatically distributed. However, this kind of service cannot operate efficiently over point-to-point networks that use conventional unique addresses.
For example, a packet sent from a source has to be copied and the addresses of a plurality of destinations have to be respectively added to the copied packets. In other words, it is necessary to generate a large number of packets to which as many different addresses as there are destinations have been added, and it takes time to generate such packets.
Moreover, in a situation where the destinations to which a packet is to be distributed are not fixed but are constantly changing, it is difficult for the source to ascertain these changes in real time, with the result that a packet may be generated for an address that has already been released. Alternatively, it may be impossible to generate a packet for a newly added address.
Another consequence can be that information which users did not request is distributed, or that information with the desired content is not distributed at all. Because information with undesired content will end up being deleted by users without being utilized, such information constitutes redundant traffic for the distribution network.
Given this background technology, it is an object of this invention to provide a push network capable of generating, by simple means, packets for use in a push service. It is a further object of this invention to provide a push network capable of responding in real time to changes in the addresses to which a packet is to be distributed. It is yet another object of this invention to provide a push network which ensures that only information with content and/or of a category which users desire is distributed. A further object of the invention is to provide a push network capable of efficiently transferring push service traffic. Yet another object of this invention is to provide a push network capable of making effective use of the memory resources in each node of a distribution network.
SUMMARY OF THE INVENTION
The principal distinguishing features of this invention are as follows. Firstly, it adds to a packet a content identifier for identifying the content, or, if a category to which the content belongs can be identified, one or both of a content identifier and a category identifier for identifying the category to which the content belongs. Secondly, a user registers in advance in the distribution network content identifier related information, or one or both of content identifier related information and category identifier related information, said information relating to the content and/or category which the user wishes to receive. Thirdly, the distribution network has content filters, or one or both of content filters and category filters, which pass packets with content, or with one or both of content and categories, wanted by a downstream user. This invention differs from the prior art in that the user sets the packet format, how the filter table is used, and the identifiers corresponding to the required content and/or category.
Namely, this invention is a push network comprising means for copying information held in a packet sent from an information providing terminal and for generating a plurality of packets with the same information, and means for distributing the packets thereby generated to a plurality of user terminals.
The distinguishing features of this invention are that it provides means for adding to a packet a content identifier for identifying the content of the information held in that packet, or for adding one or both of this content identifier and a category identifier for identifying the category to which the content belongs; and that the aforementioned distributing means comprises means for deciding, in accordance with the aforementioned content identifier, or in accordance with one or both of the aforementioned content identifier and category identifier, whether or not to distribute that packet to a given user terminal.
For example, means can be provided for adding a content identifier to a packet, and the distributing means can comprise means for deciding, in accordance with the content identifier, whether or not to distribute that packet to a given user terminal.
In this case, the decision means preferably includes a table, provided in correspondence with a destination, in which content identifier related information has been registered; and means for passing a packet if the content identifier added to that packet matches the content identifier related information registered in the table.
Means is preferably provided for registering content identifier related information in this table in accordance with notification from a user.
The result of these provisions is that it is not necessary to add, to each of a plurality of multicast packets, a respective and separate destination identifier uniquely assigned within the distribution network. Instead, it is sufficient to add the same identifier to the plurality of multicast packets, this identifier serving to identify the content of that packet, thereby simplifying the packet generation procedure.
Because the user constituting the destination can himself register in the table content identifier related information, the distribution network can recognize the content required by the user, so that transfer of useless packets can be avoided. As a result, increase in traffic is suppressed. Moreover, because the user does not receive useless packets, received information can be processed efficiently. Furthermore, because the user registers content in the distribution network, even if the situation of a user constituting a destination is constantly changing, the source can still distribute content without having to be aware of these changes.
It follows that use of a push network according to this invention ena

Affiliated with

Also associated with

Rating

Push network does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Push network, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Push network will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3300051