KR20060033558A - Device Discovery System and Method in Remote Network - Google Patents

Abstract

The present invention relates to a device search system and method in a remote network. In particular, UPnP communication is performed between UPnP devices in different networks by installing a UPnP relay module so that two physically different networks exist in the same network. The purpose is to make it possible. The present invention for this purpose, in the network connecting the UPnP equipment 230 connected to a remote network physically separated from the UPnP control point 210, is connected to the same network as the UPnP control point 210, the UPnP control M-search message of the point 210 is converted into an IP packet and transmitted to the network to which the UPnP device 230 is connected, and the IP packet responsive to the IP packet is restored to the original advertisement message to the UPnP control point ( The first UPnP relay module 250 and the UPnP device 230 are connected to the same network as the first UPnP relay module 250, and the original M-search message is transmitted from the IP packet transmitted from the first UPnP relay module 250. The second UPnP relay module 260 restores the information to the UPnP device 230 and converts the advertisement message transmitted from the UPnP device 230 into an IP packet and delivers the IP message to the first UPnP relay module 250. Characterized in that it comprises a).

Description

DISCOVERY SYSTEM AND METHOD FOR DEVICE IN REMOTE NETWORK}

1 is a block diagram showing an environment in which the discovery of UPnP equipment in the prior art is impossible.

2 is a block diagram of a device search system according to an embodiment of the present invention.

3 is a signal flow diagram illustrating a device discovery process in a remote network according to an embodiment of the present invention.

4 is a structural diagram of a transmission message and a packet in FIG.

Explanation of symbols on the main parts of the drawings

210: UPnP Control Point (CP) 220,230: UPnP Equipment

250,260: UPnP Relay Module

TECHNICAL FIELD The present invention relates to home networking technology, and more particularly, to a device search system and method in a remote network.

Universal Plug and Play (UPnP) technology is based on a distributed and open networking architecture that allows each appliance in a home network to be seamlessly peer-to-peer networking instead of centrally managed.

UPnP is a technology component of a distributed and open networking architecture that defines standard networking technologies such as IP and HTTP so that they can operate independently of the operating system, platform, and transport media.

UPnP defines a discovery protocol to discover other UPnP devices.

Discover protocol is an advertisement phase in which any UPnP device announces its presence to other UPnP devices and Control Points (CPs), and a discovery that indicates that the Control Points (CPs) are looking for UPnP devices. search).

Advertisement and search messages must be delivered to all UPnP devices and control points (CPs), so they are sent in multicast. That is, UPnP uses multicast to discover UPnP devices.

Multicast is a technology that transmits the same message to multiple hosts simultaneously in one transmission.

1 is a block diagram of a network generally presented.

When the control point 210 is newly turned on or connected to the network, the control point 210 sends an M-SEARCH message in multicast to discover UPnP devices.

Since the multicast message is transmitted to the UPnP device 220 belonging to the same network, the UPnP device 220 sends a response, and the control point 210 can discover the UPnP device 220.

However, in general, since the multicast message is delivered only to devices belonging to the same physical network, UPnP communication between devices connected to different networks is impossible.

That is, in the conventional UPnP network, a multicast message is transmitted to discover UPnP devices, but in general, the multicast message is transmitted only to devices belonging to the same physical network, so the devices are connected to different physically separated networks. There is a disadvantage in that UPnP communication between the two is impossible.

Referring to FIG. 1, the UPnP control point 110 may discover the UPnP device 120 existing on the same network through an M-search method, but different networks physically separated from the control point 210. The M-search message of the control point 110 is not transmitted to the UPnP device 130 that is connected to the control point 210 is not able to find the UPnP device 230.

Accordingly, the present invention has been designed to enable UPnP communication between UPnP devices in different networks by installing a UPnP relay module in order to improve the disadvantages of the related art so that two physically different networks exist in the same network. It is an object of the present invention to provide a system and method for discovering devices in a remote network.

The present invention provides a network for connecting UPnP equipment connected to different networks that are physically separated from UPnP control points in order to achieve the above object, and is connected to the same network as the UPnP control point and the M- of the UPnP control point. a first UPnP relay module for converting a search message into an IP packet, transmitting the UPnP device to a network to which the UPnP device is connected, and restoring an IP packet responsive to the IP packet to an original advertisement message and transmitting the same to the UPnP control point; It is connected to the same network as the equipment and restores the IP packet transmitted from the first UPnP relay module to the original multicast message and delivers it to the UPnP device, and converts the multicasted advertisement message from the UPnP device into an IP packet. Including a second UPnP relay module to deliver to the first UPnP relay module The name of a feature.

In addition, the present invention is the first and the second UPnP relay module is connected to a different network to which at least one UPnP equipment is connected to each other in order to achieve the above object and the control point of any one of the two networks ( In the UPnP device search method when connected to the first UPnP relay module side network), the UPnP control point multicasts the M-search message to discover the UPnP device, and the first UPnP relay module IP encapsulating an M-search message and transmitting an IP packet to the second UPnP relay module, and recovering, by the second UPnP relay module, an IP packet to an original M-search message to the UPnP device; Transmitting, by the UPnP device, an advertisement message for the M-search message to the second relay module; and converting the second relay module into an IP packet. And a first repeater module and the phase, of the first relay module for transmitting to, characterized in that configured to restore the original advertisement message following the steps that are transmitted to the UPnP control point.

The IP encapsulation is defined in the IETF RFC 2003. A technique for creating a virtual IP tunnel in an IP network by assuming that one IP packet is one higher protocol message and transmitting the IP header again to another host with a predetermined IP header. to be.

Hereinafter, the present invention will be described in detail with reference to the drawings.

In the embodiments of the present invention, a detailed description of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

2 is a block diagram of a network according to an embodiment of the present invention.

In FIG. 2, the UPnP control point (CP) 210, the UPnP device 220, and the UPnP relay module 250 are connected to the same network.

In FIG. 2, the UPnP device 230 and the UPnP relay module 260 are connected to the same network.

Accordingly, it can be seen that the UPnP control point 210 and the UPnP device 230 are physically separated by the Internet 240 and connected to different networks.

First, the user must input in advance the IP address and port number of the UPnP relay module 260 or 250 in another network through the user interface of the UPnP relay module 250 or 260. That is, the UPnP relay module 250 knows the IP address and port number of the UPnP relay module 260, and the UPnP relay module 260 already knows the IP address and port number of the UPnP relay module 250.

Therefore, in the embodiment of the present invention, the control point 210 communicates with the UPnP device 230 connected to a network different from that to which the network is connected. This will be described with reference to the exemplary diagram of FIG. 4.

As a first step, when the control point 210 is newly turned on or connected to the network, the control point 210 multicasts the M-SEARCH message as shown in FIG. 4 (a) to discover UPnP devices (S301).

As a second step, the UPnP relay module 250 receiving the M-SEARCH message of FIG. 4 (a) encapsulates the message into an IP packet again, and uploads the IP packet of FIG. 4 (b) to the UPnP relay module 260. Will be delivered to (S302).

As a third step, the UPnP relay module 260 extracts the M-SEARCH message of FIG. 4 (a), which was originally multicasted by the control point 210, from the IP encapsulated IP packet and transmits the multicast to the local network in multicast. (S303).

As a fourth step, the multicast message in step S303 is delivered to the UPnP device 230. In response to this, the UPnP device 230 sends an advertisement message as shown in FIG. 4 (c) by multicast, and the multicast message is transmitted to the UPnP relay module 260 (S304).

As a fifth step, the UPnP relay module 260 receiving the advertisement message sent by the UPnP device 230 again encapsulates the IP and sends an IP packet as shown in FIG. 4 (d) to the UPnP relay module 250 (S305).

As a sixth step, the UPnP relay module 250 extracts the IP packet of FIG. 4 (d) again from the original UPnP device 230 and sends an advertisement message as shown in FIG. 4 (c) to the local network in multicast ( S306).

As a seventh step, the control point 210 receives an advertisement message and discovers the UPnP device 230.

Since the steps of wpDescription, Control, Event, etc. are all made through the HTTP protocol over TCP, UPnP communication for the step between the control point 210 and the UPnP device 230 is UPnP standard without the help of the UPnP relay module (250,260) According to (S307).

Meanwhile, in addition to the IP Encapsulation method, communication between UPnP relay modules 250 and 260 may be performed by creating a separate protocol that can transmit and receive M-SEARCH or advertisement message.

As described in detail above, the present invention installs a UPnP relay module to recognize two different physically separated networks as if they are the same network, thereby enabling UPnP communication between different networks so that UPnP equipment can be easily controlled remotely. Will be effective.

Claims (6)

In a network system connecting UPnP devices connected to a remote network physically separated from the UPnP control point, It is connected to the same network as the UPnP control point, converts the M-search message of the UPnP control point into an IP packet, and transmits the IP packet to the network to which the UPnP device is connected. A first UPnP relay module for restoring a message to the UPnP control point; It is connected to the same network as the UPnP device, restores the IP packet transmitted from the first UPnP relay module to the original M-search message, and delivers it to the UPnP device, and transmits the advertisement message transmitted from the UPnP device to the IP packet. And a second UPnP relay module which converts the data to the first UPnP relay module and converts it to the first UPnP relay module. The method of claim 1, wherein the first and second UPnP relay module A device search system in a remote network, characterized in that the other party's IP address and port number are input in advance. 2. The system of claim 1, wherein the M-search message and the advertisement message are multicast within a local network. Assume that the first and second UPnP relay modules are connected to different networks to which at least one UPnP device is connected, and the UPnP control point (CP) is one of the two networks (the first UPnP relay module side network). In the UPnP device search method of the network system connected to the), The control point multicasting the M-search message to discover the UPnP device; A first UPnP relay module IP-encapsulating the M-search message and transmitting an IP packet to the second UPnP relay module; Restoring, by the second UPnP relay module, the IP packet to the original M-search message and multicasting the IP packet to the UPnP device; Multicasting, by the UPnP device, an advertisement message for the M-search message to the second UPnP relay module; Converting the second UPnP relay module into an IP packet and transmitting the IP packet to the first UPnP relay module; Multicasting the first UPnP relay module to the UPnP control point by restoring an original advertisement message; And detecting, by the UPnP control point, an advertisement message and discovering the UPnP device in a network different from that of the UPnP control point. 5. The method of claim 4, comprising performing direct communication with the UPnP device in which the UPnP control point is found based on the UPnP standard. 5. The method of claim 4, further comprising inputting and recording an IP address and a port number of the counterpart relay module in the first and second UPnP relay modules. 6.

Images