KR100690609B1 - Direct communication method between home network device and internet device - Google Patents

Abstract

The present invention provides a home network device and the Internet for direct communication between a device on a home network assigned with an unauthorized IP that cannot be recognized on the Internet, and an external device on the Internet assigned a public IP that can be recognized on the Internet. A direct communication method of a device, the method comprising: obtaining public IP information assigned to an Internet gateway device (IGD) of an Internet subscriber to which an external device is to be connected; When there is a request for information on a device on a home network from the external device, the IGD recognizes each device on the home network through multicast and obtains private IP information and port information assigned to each recognized device. Wow; Generating a packet having an IP of the home network device as a header and tunneling the packet having the IP of the IGD as a header; And transmitting the IP tunneled packet to the IGD and removing the header of the packet from the received IGD, and transmitting the IP tunneled packet to the home network device having the IP of the inner packet header.

Description

Direct communication between home network device and internet device {DIRECT COMMUNICATION METHOD BETWEEN HOME NETWORK DEVICE AND INTERNET DEVICE}

1 is an exemplary view showing a communication method of a home network device using a conventional private IP and an external device using a public IP.

2 is an exemplary view showing a method of obtaining an IP assigned to a subscriber IGD (Internet Gateway Device) from an external device according to the present invention.

3 is an exemplary view showing a multicast scheme for finding a usable device on a home network in a UPnP device according to the present invention.

Figure 4 is an exemplary view showing a communication method of a home network device using an unauthorized IP and an external device using a public IP according to the present invention.

5 is a flowchart illustrating a method for transmitting a packet generated by IP tunneling from an external device to a home network device according to the present invention.

The present invention relates to a direct communication method between a home network device and an Internet device, and more particularly, a device on a home network assigned an unauthorized IP that cannot be recognized on the Internet, and an external device on the Internet assigned a public IP that can be recognized on the Internet. The present invention relates to a direct communication method between a home network device and an Internet device, which enables direct communication between devices.

In general, a home network is formed by a private network based on an Internet Protocol (IP). The home network includes various types of devices such as personal computers (PCs), intelligent products, and wireless devices. It is connected and controlled by one network.

As described above, the home network aims to interconnect devices in the home, but the user wants to control the devices in the home from the outside. In other words, since the Internet can be used anytime and anywhere due to the recent spread of the high speed communication network and the development of mobile communication network, it is intended to control the devices in the home through the Internet which can be easily accessed from anywhere.

However, the problem is that not all home network devices in the home can be assigned a public IP, and that public IP assigned to an Internet Gateway Device (IGD) by an Internet Service Provider (ISP) is also dynamic ( The IP is not known from outside because it is assigned to Dynamic.

In other words, the home network devices in the home are standardized (UPnP) of the home network to connect based on IP, so that even devices of different manufacturers can communicate and communicate with other devices outside the home through the Internet. Yes, but not all devices in the home are given public IP.

Therefore, in a typical home, only one public IP is assigned from the Internet service provider (ISP) to use the Internet, and a method of sharing the allocated public IP with multiple devices through NAT (Network Address Translation) is also used. Restrictions apply when communicating with external devices on the network.

Next, a communication method of a home network apparatus using a conventional private IP will be described with reference to the exemplary diagram of FIG.

Referring to FIG. 1, an application of a device B, which has been granted an unauthorized IP in a home network, can access an application of the device A through a port number of a device A having an external public IP, and establish a NAT service of the IGD. Data can be transmitted and received through However, there is no way to connect to an application of home network device B having a private IP from an application of external device A.

If the application of the home network device B registers the IP and port number to the NAT service of the IGD (Internet Gateway Device), the application of the external device A is mapped to the public IP of the IGD and the application of the device B registered in the IGD ( Although it is possible to know the port number to be mapped in advance, it is possible to access the home network device from an external device because most applications dynamically allocate the port number.

Therefore, the present invention was created to solve the above-mentioned conventional problems, the device on the home network is assigned an unauthorized IP that can not be recognized on the Internet, and on the Internet assigned a public IP that can be recognized by the Internet An object of the present invention is to provide a direct communication method between a home network device and an Internet device, which enables direct communication between external devices.

The present invention for achieving the above object comprises the steps of obtaining the public IP information assigned to the Internet Gateway Device (IGD) of the Internet subscriber to the external device to access; When there is a request for information on a device on a home network from the external device, the IGD recognizes each device on the home network through multicast and obtains private IP information and port information assigned to each recognized device. Wow; Generating a packet having an IP of the home network device as a header and tunneling the packet having the IP of the IGD as a header; And transmitting the IP tunneled packet to an IGD, removing the header of the packet from the received IGD, and transmitting the IP tunneled packet to the home network device having the IP of the inner packet header.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First of all, in adding reference numerals to the components of each drawing, it should be noted that the same components have the same reference numerals as much as possible even if displayed on different drawings.

Also, in the following description, numerous specific details, such as specific processing flows, are set forth in order to provide a more general understanding of the invention, and it is to be understood that the invention may be practiced without these specific details. It will be obvious to them.

In addition, detailed description of well-known functions and structures which are determined to unnecessarily obscure the subject matter of the present invention will be omitted.

First, in the present invention, public IP information allocated to the IGD of the subscriber is obtained from the Internet service provider (ISP) by using unique information (for example, a telephone number and a MAC address) for each Internet service subscriber (subscriber device).

In other words, most ISPs provide wired telephone service together, and the wired telephone is also converted to VoIP (Voice over IP) Internet phone. In this case, the subscriber's unique information is provided to IGD. You can easily get the assigned public IP.

Even if the ISP does not provide the wired telephone service, IP is mapped 1: 1 with the MAC address. Therefore, if the ISP stores the subscriber's general telephone number and the IGD MAC address, it is dynamically allocated to the IGD for each subscriber. You can see the IP.

For example, as shown in Fig. 2, the external device A, which wants to connect to any home network device, accesses the ISP server 10 via the Internet, and connects to the subscriber via the general telephone number of the subscriber. Receiving the public IP assigned to the IGD of the ISP, the server of the ISP stores the IP information for the external device A that has requested the subscriber's IP information for a predetermined period of time, and the IP information assigned to the IGD is changed during the period. If the connection is lost (for example, disconnected and then reconnected), it will be notified automatically.

Next, the external device that finds the public IP information assigned to the IGD of the subscriber to be connected as described above, through the public IP as shown in Figure 4 to obtain information about the home network device to be connected Connect to the well-known port A of the IGD. In this case, when the external device is a mobile communication terminal, the external device is connected to the Internet through a mobile network.

Meanwhile, the port A of the IGD receiving the information request from the external device recognizes each device in the home network through multicast, receives a description of each device, and delivers the information to the external device. In this case, the private IP and port number of the home network device are recorded in the device description according to the definition of UPnP.

Meanwhile, in the present invention, the port A performs a function of a control point (CP) of UPnP, and when there is a change in each device information in the home network, the port A recognizes this and informs the external device. You will continue to know the IP and port number for each device on your home network.

For reference, in the UPnP (Universal plug and play), which is a home network standard, as shown in FIG. 3, the CP uses a multicast method to find an available device on the home network, and receives a multicast packet. By notifying the device, the device notifies the information about itself, so that the device can find a device currently available in the home network.

Next, the external device that has obtained the information (private IP information, port number) about the home network device to be connected as described above connects to the home network device using the private IP and the port number.

Next, a case in which the external device attempts to transmit a packet destined for an unapproved IP of a home network device received from port A will be described in more detail with reference to FIG. 5.

First, the external device creates an IP header destined for the designated well known port B of the corresponding IGD, and a packet to be delivered to the data field (a packet composed of private IP + data of a home network device). ) To perform IP tunneling. In this case, since the public IP uses a different area from the public IP, communication between the external device and the other public IP does not cause a problem.

Next, the IGD receiving the packet through the designated port B removes the header of the packet and delivers the packet to the actual destination (home network device) in the home network.

As described above, the present invention obtains public IP information assigned to an IGD of a subscriber to which an external device wants to access by telephone number information mapped to an ISP server, and provides information on an internal device of a home network having an unauthorized IP through the IGD. IP tunneling enables connection to a home network device having the private IP.

As described above, the direct communication method between the home network device and the Internet device of the present invention includes a device on a home network assigned with an unauthorized IP that cannot be recognized on the Internet, and an external device on the Internet that is assigned a public IP recognized on the Internet. There is an effect that allows direct communication between devices.

Claims (7)

Obtaining public IP information assigned to an Internet gateway device (IGD) of an Internet subscriber to which an external device is to be connected; When there is a request for information on a device on a home network from the external device, the IGD recognizes each device on the home network through multicast and obtains private IP information and port information assigned to each recognized device. Wow; Generating a packet having an IP of the home network device as a header and tunneling the packet having the IP of the IGD as a header; Transmitting the IP tunneled packet to an IGD, removing the header of the packet from the received IGD, and transmitting the IP tunneled packet to a home network device having an IP of an internal packet header. Method of direct communication of the device. The method of claim 1, wherein the public IP information assigned to the Internet subscriber's IGD is obtained by obtaining a subscriber's telephone number mapped to an Internet service provider (ISP) server or device information (MAC address) of the IGD. Direct communication method between the home network device and the Internet device. The method according to claim 2, wherein the ISP server stores information on the external device that has requested the IP information of the subscriber IGD for a predetermined period of time, and automatically notifies the IP information allocated to the IGD during the period. Direct communication method between the home network device and the Internet device, characterized in that made. The home network device according to claim 1, wherein the information on each device of the home network to which the external device is to be connected is obtained by accessing a predetermined port A (Well known port A) designated in the subscriber IGD. And direct communication of Internet devices. The device of claim 4, wherein the port A of the IGD, which recognizes and transmits information about each device of the home network, to the external device, obtains a description of each device in the home network through multicast, and uses CP of UPnP. A method of directly communicating between a home network device and an internet device, wherein the home network device is configured to notify an external device when information on each device of the home network is changed by performing a function of a control point. According to claim 1, When the external device to communicate by connecting to the desired home network device using a private IP received through the port A of the IGD, through a predetermined port B (Well known port B) for communication A method of direct communication between a home network device and an internet device, characterized in that it transmits and receives packet data. 2. The IP tunneling packet of claim 1, wherein the IP tunneling packet comprises an IP header destined for an IGD having a public IP, and a packet to be actually forwarded to the data field (non-private IP + data of a home network device). Direct communication between the home network device and the Internet device, characterized in that the packet is generated.

Images