JPH04349737A - Packet exchange system with broadcast service function - Google Patents

Abstract

PURPOSE:To relieve the load of large consumption of a resource of an exchange resulting from setting of one to one connection call by number of broadcast destinations when the broadcast service is realized in the packet exchange system. CONSTITUTION:A packet 10 desired to be distributed by the broadcast service of a layer 3 is given to a subordinate layer 2 through a broadcast service access point 51. The packet is composed into a frame 20 in the layer 2 and given to a subordinate ATM adaptation layer(AAL) through a broadcast service access point 52. The frame in the ATM adaptation layer is divided into a cell 30 and a broadcast identifier is written in a header at that time. An ATM exchange 40 distributes cells to a noticed broadcast destination from a system management 50 at setup.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet switching system, and more particularly to a packet switching system having a broadcasting service function.

0002

2. Description of the Related Art At present, there is no packet-switched device with a broadcasting service function. Therefore, when distributing data from an information sending source to multiple broadcasting partners, 1
There is a method in which 1 call is set for each broadcast destination.

0003

[Problems to be Solved by the Invention] In a method that uses conventional one-to-one packet switching technology to set up calls as many times as there are broadcast destinations, switching equipment resources are consumed significantly and transmission delays vary depending on the call. There is a problem.

0004

[Means for Solving the Problems] The packet switching system with a broadcasting service function of the present invention is a method for switching between layer 3 and layer 2 in a one-to-many packet communication service in which data from an information sending source is distributed to a plurality of parties. A first broadcast service access point is provided between the layer 2 and the ATM adaptation layer, and a second broadcast service access point is provided between the layer 2 and the ATM adaptation layer, and from the layer 3 to the first and second broadcast service access points. This configuration copies and distributes data delivered through the ATM layer at the ATM layer.

[0005]

[Operation] The packet switching system with broadcasting service function of the present invention uses the broadcasting function of an ATM switching device in the ATM layer. Therefore, first, a service access point for broadcasting service is defined between layer 3 and layer 2. From the perspective of layer 3, it is assumed that broadcasting services are performed when packets are passed to lower layers using this access point. Next, service access points for broadcasting services are similarly defined between layer 2 and the intra-layer 1 ATM adaptation layer. From the perspective of layer 2, it is assumed that a broadcast service is performed when frames are passed to the ATM adaptation layer using this access point. In the ATM adaptation layer, frames passed through the broadcast service access point are assembled into cells with broadcast service identifiers, and this is sent to the ATM switching equipment, where it is duplicated and distributed to the other party.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows the data flow and protocol layer of one embodiment of the present invention. A packet 10 to be distributed by the layer 3 broadcast service is passed to the lower layer 2 through the broadcast service access point 51. At Layer 2, this is assembled into a frame 20 and passed to the lower ATM Adaptation Layer (AAL) through the broadcast service access point 52 as well. In the ATM adaptation layer, this frame is divided into cells 30, and at this time a broadcast identifier is written in the header. A.T.
In the M switching device 40, the system management 5 at the time of call setup
A plurality of cells are distributed to the broadcasting destinations notified by 0.

Note that the service access point shown in FIG. 1 is different from the conventional service access point, which is an access point from a lower layer to an upper layer.Since the service request is from the upper layer to the lower layer, the lower layer is an access point from the upper layer. You will need to look at the header. In Figure 1, “
The broadcast service access point 51 sends "LCN in the packet header = x" to layer 2, and
I=y' is the broadcast access service point 52 to the ATM adaptation layer. Also, “V in the cell”
It is assumed that "VCI=Z" is a broadcast service provided to destinations A, B, and C, with "CI=Z" as a broadcast identifier. As a broadcasting service destination, the system management 50 is notified from layer 3 at the time of call setup, and the system management 50
then notifies the ATM switching device 40.

[0009]

[Effects of the Invention] As explained above, the present invention reduces the amount of information transferred in layers 2 and 3 because the processing of duplication and distribution, which can be said to be the operating principle of broadcasting services, is performed in the ATM layer, which is a lower layer. Yes, layer 2, layer 3
The load on processing capacity can be reduced. Furthermore, the transmission delay does not vary depending on the broadcast destination.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the data flow and protocol layer of one embodiment of the present invention.

[Explanation of symbols]

10 Packet 2 with LCN=x in packet header
0 Frame 3 with DLCI=y in frame header
0 Cell 40 with VCI=Z in cell header
ATM switching equipment 50 system management

Claims (1)

[Claims] Claim 1: In a one-to-many packet communication service in which data from an information transmission source is distributed to a plurality of parties, a first broadcast service access point is provided between layer 3 and layer 2; A second broadcasting service access point is also provided between the layer 3 and the ATM adaptation layer, and the data transferred from layer 3 through the first and second broadcasting service access points is replicated and distributed at the ATM layer. Characteristic packet switching method.