JP2003198553A - Simultaneous command communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a server to surely receive command reception confirmation data from a client by avoiding the collision of packets when returning the command reception confirmation data in response to simultaneous command data receiving from the server by UDP packets by a plurality of clients. <P>SOLUTION: In order to avoid the occurrence of the collision caused by the simultaneous transmission of command reception confirmations from the plurality of clients to the server, after the end of simultaneous command data transmission, the server transmits a command reception confirmation request packet. With the receiving time of this packet as a reference, each of clients generates a delay time determined by the intrinsic number of a present station by itself and transmits the command reception confirmation data to the server successively while having a time difference. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simultaneous command communication system.

[0002]

2. Description of the Related Art Internet Protocol (hereinafter referred to as IP
In a network using (for abbreviated), for example, the communication procedure as a means for a data distribution source to simultaneously distribute the same image data to a plurality of parties adopts a User Datagram Protocol (hereinafter abbreviated as UDP). is doing. The protocol is generally called a postcard method, and in communication in a relatively small local area network, the communication speed is high because it is a method of communicating without obtaining the consent of the communication partner, and it is simultaneously distributed to many partners. It is an effective protocol as a means to do. On the other hand, for example, when applied to a disaster prevention wireless system, in simultaneous command communication, a control station is installed in a terminal station that receives the command data transmitted from a server installed in the control station. It is mandatory to get the order confirmation data from the client. When multiple clients send back the order confirmation data to the server at the same time, the order confirmation data collides, and the server of the control station, which is the source of the simultaneous command, cannot receive the order confirmation data normally. .

[0003]

When the client of the terminal station sends a UDP packet as a response means to the simultaneous command data distribution from the server of the control station, a plurality of clients can simultaneously or independently receive the acceptance confirmation data. U
When a DP packet is returned, the UDP packet collision may occur, and the server may not normally receive the UDP packet. An object of the present invention is to avoid collision between the packets when a plurality of clients return the acceptance confirmation data for receiving the simultaneous command data from the server in a UDP packet, and to receive the acceptance confirmation data from the clients in the server. It is necessary to ensure reception.

[0004]

In order to solve the above problems, a simultaneous command channel is provided for simultaneous command data distribution from a server to a plurality of clients, and when a client receives the distribution data. After setting up a response channel for replying to the confirmation data and receiving the simultaneous command data from the server to multiple clients,
UD requesting each client to return receipt confirmation data
A means for creating and transmitting a P packet is provided, and each of the clients has a predetermined response sequence number of its own station based on the UDP packet reception time of the acceptance confirmation request distributed by the server from the simultaneous command. According to the above, UDP packets of acceptance confirmation data are sequentially transmitted to the response channel.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS.
2 will be described. FIG. 1 shows a network according to an embodiment of the present invention.
FIG. 2 is the server and client of FIG.
It is a figure showing exchange of data or a command between them.
1 is a server installed in the control station etc. 2 is installed in the terminal station etc.
A client installed, for example, a personal computer
3 is a group from the server 1 that transmits the simultaneous command data.
Broadcast command channel to client 2 and 4 for each client
It is a response channel from the host 2 to the server 1. Next action
Will be explained. Simultaneous command from server 1 to each client 2
UDP packet of "simultaneous command activation" using channel 3
To send. Next, in the same way as above,
UDP₁~ UDP_kSend in packets. here
And the UDP₁~ UDP_kPackets are commanded simultaneously
Is divided into a plurality of packets. Then as above
After sending the batch command data to be sent
"Request" UDP packet to all clients by simultaneous command
Send. A predetermined time T from the transmission₀And the first club
Client n from client 2-1 is n
To the UDP packet using the response channel 4
Reply in sequence. The order of the replies avoids collisions
Therefore, each of the clients 2-1 to 2-n has T₀, T
₀+ Τ, T₀+ 2τ, ..., T₀+ (N-1) τ delay
UDP of the order confirmation data to the server 1 with each space
Send a packet. The last client 2-n is T₀
(N-1) τ hours later, sending the order confirmation data to the server 1
When the server 1 receives the acceptance confirmation data,
Server 1 sends "end notification" to all clients 2.
Send UDP packet to each client by simultaneous command
Then, the communication sequence of the simultaneous command ends.

[0006]

The polling system in which the server and the client in the client system make inquiries to the clients sequentially from the server is used. However, the system of the present invention does not require inquiries. The collection time can be significantly reduced. Also, since communication using UDP packets is one of the standard procedures of the IP protocol, even if the makers in charge of the server and the client are different, it is possible to connect easily.

[Brief description of drawings]

FIG. 1 is a network configuration diagram of an embodiment of the present invention.

FIG. 2 is a sequence diagram of a simultaneous command communication operation according to an embodiment of the present invention.

[Explanation of symbols]

1: server, 2: client, 3: simultaneous command channel, 4: response channel

Claims (2)

[Claims] 1. In a simultaneous command communication system in a wired line or wireless line communication system composed of a server and a plurality of clients, a means for transmitting simultaneous command data from a server to each client, and each of the simultaneous command data. The means for receiving by the client, the means for transmitting the acceptance confirmation data indicating that each client has received the simultaneous command data to the server, and the means for the server receiving the acceptance confirmation data, the transmitting and receiving means. As the above, a simultaneous command communication method characterized by having a user datagram protocol packet. 2. The simultaneous command communication system according to claim 1, wherein when each client transmits acceptance confirmation data to the server, each client sets a delay time corresponding to a unique number of its own station with respect to a predetermined reference time. A simultaneous command communication system comprising means for generating and transmitting the acceptance confirmation data at a time when the delay time is added to the reference time.