KR100426519B1 - Multicast Packet Communication Method of Mobile Communication Device - Google Patents

Abstract

The present invention relates to a multicast packet communication method using a mobile communication terminal, comprising: a first step in which at least one mobile communication terminal receives an IP address through a packet data service; and a sending terminal has a class D multicast IP address. A second step of creating a multicast group by designating a multicast group, and transmitting and notifying information on the generated multicast IP address to a mobile communication terminal of one or more receivers; And a fourth step of transmitting a data packet of the first step, and one or more receiver terminals having obtained the multicast IP address join the corresponding multicast group and receive the transmitted data packet.

The present invention enables 1: n packet communication using a mobile communication terminal, which enables not only to transmit multimedia data in one terminal to a plurality of other terminals at a time, but also teleconference such as video or audio conference. The mobile communication terminal can be used.

Description

Multicast packet communication method using mobile communication terminal {Multicast Packet Communication Method of Mobile Communication Device}

The present invention implements a multicast packet communication method using a mobile communication terminal, and more specifically, data held by a sender's terminal by implementing multicasting between mobile communication terminals that are assigned an IP using a packet data service (multimedia contents). The present invention relates to a method for sharing a transmission to a specific plurality of recipient mobile communication terminals.

Recently, with the widespread use of mobile communication services, almost all citizens are provided with one or more mobile communication services. These mobile communication services are expanding to basic voice calls, text and voice message transmission and reception, wireless Internet services, and contents for mobile communication terminals.

In particular, the wireless Internet service may receive a fixed or dynamic IP address by requesting a gateway and transmit / receive packet data with another server or client using the IP address. It is applied to various fields such as online games, content download, and information search.

In such a wireless Internet service using a terminal, only a unicast scheme in which a sender and a receiver communicate one-to-one is used. That is, a packet is transmitted by designating an IP address of one destination host through a transfer control protocol (TCP) or a user datagram protocol (UDP).

Meanwhile, in addition to the unicast method, the Internet communication using a computer system includes a broadcast method that propagates a packet as if it is broadcast to a large number of unspecified persons, and a multicast method in which a sender delivers a packet to a specific number of recipients. The method is used.

Among these, multicast transmits the desired data packet to the multicast IP address by the sender's computer system using the D class among the IP classes, and then delivers the data packet to the multiple hosts to be received by using the multicast router and tunneling. do.

This multicast method is useful for conferencing (voice and video conferences) among users belonging to a specific group or sharing data with each other while reducing network load by simultaneously copying and transferring information from one system to multiple systems. It can be used to.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and by implementing a multicast of a mobile communication terminal that can use the Internet packet service, to provide a method for sharing multimedia data or performing video conferencing between multiple terminals, etc. For sake.

An object of the present invention is to provide a method for implementing IP multicast using a mobile communication terminal.

Another object of the present invention is to provide various services such as sharing (forwarding) (multimedia) data, teleconferencing, and remote lecture by implementing IP multicast of a mobile communication terminal.

1 shows the overall configuration of a system for implementing the method according to the invention.

2 shows an overall flow diagram for implementing the method according to the invention.

In order to achieve the object as described above, the present invention

A first step in which at least one mobile communication terminal is given an IP address through a packet data service;

A second step of the sending terminal designating a multicast IP address of class D to generate a multicast group, and transmitting and notifying the information on the generated multicast IP address to one or more receivers' mobile communication terminals;

A third step of sending, by the transmitting terminal, a predetermined data packet to the set multicast IP address;

And a fourth step of joining the multicast group with at least one receiver terminal having obtained the multicast IP address in the second step, and receiving the transmitted data packet.

In addition, if the receiver no longer wants to receive data, the receiver may further include a fifth step of leaving the multicast group.

The method of notifying the multicast IP address generated in the second step may use a short message service, and the receiver searches for the multicast IP address by using the Session Directory (SDR) program without the sender actively notifying. You may extract.

In order to transmit desired data to the generated multicast group, the transmitting terminal may make the data to be transmitted into a UDP packet and transmit the data to the multicast group address. When a host sends UDP packets to this multicast group, the multicast routers forward all the multicast subscribing hosts that they manage to receive the packets.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

1 shows the overall configuration of a system for implementing the method according to the invention.

The entire system connects the Internet network 120 including one or more mobile communication terminals 110, one or more multicast routers 121, and a gateway (not shown), the mobile communication network 130, and the mobile communication network and the Internet network. It consists of a network (140).

The mobile communication terminal 110 should be able to use an IP-based packet data service (n-top service, etc.), and use the Internet Group Management Protocol (IGMP) and Internet Control Management Protocol (ICMP) to perform multicast. You must have an application installed to support it.

These applications can create multicast groups and send data packets to them, and request neighboring multicast routers to search for specific multimedia groups and join and leave them. The receiving function must be implemented.

In addition, a packet service support function of a general mobile communication terminal, that is, a function of receiving a fixed IP or a dynamic IP by connecting to an IWF / PDSN network or an exchange (MSC), and another Internet-enabled device (an external server or terminal having an IP) PPP session establishment, TCP session establishment, etc., and the function to packetize the data to be transmitted according to TCP or UDP, and to send to the router through the mobile communication network and the Internet network and the like.

As long as the above-described various functions are provided, the specific form of the mobile communication terminal is not limited and is a broad concept including all terminals such as GSM or CDMA type cellular phones, PCS, IMT-2000, PDA, handheld PCs, and the like.

The internet network 120 refers to a plurality of computer networks standardized by IP protocols, and includes a plurality of servers, clients, and routers for delivering packets. Some of these routers are multicast routers 121 that send a Host Membership Query to the local network under their management to discover which host groups contain multicast subscribers. And receiving a Host Membership Report sent from the host to the router in response thereto.

In addition, the Internet network 120 is responsible for the conversion between the data that can be recognized by the mobile communication terminal and the data transmitted from the Internet network according to a protocol adopted by the mobile communication terminal, for example, a wireless application protocol (WAP). A gateway (not shown) is further provided. Such a gateway may be implemented using, for example, a WAP gateway or the like.

The mobile communication network 130 includes at least one base station (BS) and a mobile communication exchange (MSC), and a detailed description thereof will be omitted.

The connection network 140 connecting the mobile communication network and the Internet network refers to a so-called inter-working function (IWF), and data between a physical computer network or a telephone network (PSTN) and a mobile communication network implementing the Internet network. It is in charge of the transformation.

2 shows an overall flow diagram for implementing the method according to the invention.

First, the sender obtains an IP address through a packet data service request of a terminal (S211). Next, a multicast group is generated by selecting one of the multicast IP addresses belonging to class D (S212). The IP address for multicast is selected from 224.0.0.0 to 239.255.255.255.

Next, the generated multicast group information is notified to a specific receiver (S213).

For this notification, the sender terminal may use a first method of creating a text message including a multicast IP address generated after the multicast group is generated and transmitting it to one or more preset receiver terminals (S214). When the receiver receives the text message, the receiver acquires an IP when the receiver wants to receive data from the sender, and joins the multicast group (S215 and S218).

Of course, without receiving the IP address for the multicast through active message transmission, the receiver acquires the IP address and then searches for and extracts the desired multicast IP address using the SDR program installed in the terminal. The scheme may be used (S216, S217).

Session Directory (SDR) refers to a program that displays a list of ongoing sessions (multicast groups) on the Internet (in particular, MBone, a network for multicast). This SDR can be used not only when the receiver searches for a desired multicast group, but also to prevent collisions of existing group addresses when the sender creates a multicast group. That is, a user who wants to create a multicast group can find out the IP address of a group that exists in advance using SDR, and select his multicast group IP address by avoiding it.

A receiving terminal receiving a text message including a multicast IP address or searching for a multicast group created by a sender using SDR designates the multicast IP address as a group address, and the IP module provided in the terminal. Joins the multicast group by requesting to join the desired group.

Such a join request can be performed by sending a message written using an appropriate program function, for example, a function such as JoinHostGroup (group-address, interface) to an adjacent multicast router.

When a new receiver terminal (host) joins a multicast group, the host sends an IGMP message to the neighboring multicast router to indicate that it is joined to the multicast group, and the router informs other multicast routers that are connected to each other. Give this information. This completes the multicast group join of the receiving terminal (S218).

Next, the sender selects data to be sent in a multicast manner and transmits the packet to the receiver terminal subscribed to the group (S219). The transmitted data packet is delivered via multicast routers to the terminals joining the group. There is no limit to the data to be transmitted, but since the object of the present invention is data sharing, video conferencing, etc., it will mainly be multimedia data. That is, video, sound, image information, etc. will be applicable.

Of course, if there is a special purpose such as video conferencing, rather than simply transmitting data, an application program such as a video conference tool (VIC), etc., should be installed in the terminal.

This data transmission is performed by the sending terminal packetizing the selected data according to UDP and transmitting the packet with the corresponding multicast IP address as the destination.

Intermediate multicast routers that connect hosts (mobile nodes or mobile terminals) that are joined to the multicast group run the Multicast Routing Protocol (MRP). The multicast router transmits the transmitted packets to the subscribed terminals.

In order to transmit multicast packets between routers, encapsulated packets are transmitted between the multicast routers using the concept of tunneling. In other words, by routing IP packets at both ends of a tunnel set between multicast routers in front of a data packet header having a multicast IP address, the same packet as a conventional unicast packet when passing through general routers that do not support multicast. It is routed in such a way that it can be finally sent to the end of the tunnel.

The receiver terminal receives the multicast packet using a "receive IP" operation as in the normal unicast packet reception (S220).

If the receiver no longer wants to receive the multicast packet or if all data has been received (S221), the receiver may leave the corresponding multicast group (S222). The revocation can be done by creating an IGMP message and sending it to an adjacent multicast router using operations such as LeaveHostGroup (group-address, interface), just like a subscription. After the withdrawal, transmission (reception) of all packets with the multicast IP address is stopped.

As described above, the method according to the present invention enables 1: n packet communication using a mobile communication terminal, so that multimedia data and the like in one terminal can be simultaneously transmitted to a plurality of other terminals.

In addition, by using a mobile communication terminal in a teleconference such as a video or audio conference, it will be possible to dramatically improve the utilization of the terminal.

Claims (5)

A first step in which at least one mobile communication terminal is given an IP address through a packet data service; A second step of the sending terminal designating a multicast IP address of class D to generate a multicast group, and notifying information on the generated multicast IP address to a mobile communication terminal of at least one receiver; A third step of sending, by the transmitting terminal, a predetermined data packet to the set multicast IP address; And a fourth step of joining the multicast group with at least one receiver terminal having obtained the multicast IP address in the second step, and receiving the transmitted data packet. Multicast packet communication method using a communication terminal. The method of claim 1, And a fifth step of withdrawing from the multicast group if the receiver has received all the desired data or no longer wants to receive the data. The method of claim 1, Notifying the multicast IP address generated in the second step, A first method of generating a short message including the multicast IP address and transmitting the short message to a designated receiver terminal; A second method in which the receiver searches for and extracts the multicast IP address using an SDR (Session Directory) program without the sender actively notifying; Multicast packet communication method using a mobile communication terminal, characterized in that implemented by one or more of. The method of claim 1, Joining to the multicast group in the fourth step, Mobile communication characterized in that the receiver terminal generates an IGMP message indicating that it is participating in the multicast group and sends it to an adjacent multicast router, and the router receiving the IGMP message is notified to other multicast routers connected to each other. Multicast packet communication method using a terminal. The method of claim 1, The third step of data transmission, And transmitting the packet by packetizing the selected data according to User Datagram Protocol (UDP) and transmitting the packet by using the corresponding multicast IP address as a destination address.