KR101394609B1 - Control point and home gateway for receiving event provided from device in remote place - Google Patents

Abstract

According to an embodiment of the present invention, a control point located in a private network registers a callback access address for receiving an event from a device located at a remote location to a device located at a remote location.
At this time, if the callback access address is a private IP address, the callback access address is changed to the public IP address of the home gateway connected to the control point and the external port number set for port forwarding by the home gateway.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control point and a home gateway for receiving an event provided by a device located at a remote location,

The present invention relates to a control point and a home gateway for receiving events provided by a device located at a remote location.

In general, a home network is made up of an IP (Internet Procotol) -based private network. Such a home network connects various types of devices used in the home by a single network through a common virtual computing environment called middleware. Middleware refers to a home AV interoperability (HAVI), a universal plug and play control device (UPnP), and the like, which enable communication between devices by connecting various digital devices in a peer-to-peer manner. , Java Intelligent Network Infrastructure (Jini), and Home Wide Web (HWW).

In particular, UPnP is an IP-based (Internet Protocol) protocol used for communication between devices located in a home network based on internet standard technologies such as transmission control protocol / internet protocol (TCP / IP), hypertext transfer protocol (HTTP) and extensible markup language Standard protocol technology.

Meanwhile, standardization of a UPnP remote access (hereinafter referred to as 'RA') 1.0 technology for providing the same function as located in a home network has been completed for a device located at a remote location.

1 is a block diagram illustrating a conventional Universal Plug and Play (UPnP) RA architecture. At this time, the UPnP remote access architecture of FIG. 1 is cited in the UPnP Forum's Remote Access Architecture v1.0 document.

Referring to FIG. 1, a remote access client (RAC) 100 and a remote access server (RAS) 200 are commonly connected to a remote access server Discovery Agent) 110 and 210, and includes RAC 120 and RAS 220, respectively.

The RADAs 110 and 210 are connected to the UPnP device list of the RAC 100 through the RADASync 112 and 211 and the RADASync CPs 113 and 212 and the UPnP devices 100 and 210 operating on the home network to which the RAS 200 belongs, Synchronize device list. And processes a Simple Service Discovery Protocol (SSDP) message so that the UPnP CP on the home network to which the UPnP CP belongs can discover the UPnP device on the remote network.

Here, the RADA 110 of the RAC 100, the RAC 120, and the RADA 210 of the RAS 200 represent a UPnP device. The RADASync CP 113 of the RAC 100 and the RADASync CP 212 of the RAS 200 represent a remote connection related UPnP control point CP and the control point is not included in the UPnP device.

The RADASync 112, the RATAConfig 121 and the inbound connection config 221 of the RAC 100, the RADAConfig 223 and the RATAConfig 224 of the RAC 100 represent a remote connection related UPnP service. The RAC 100 and the RAS 200 provide the RADA Config 223 and the RATA Config 121 and 224 services for setting the functions for the RADA and the RATA. At this time, the RATA generates a RA transport channel to provide a communication channel between the RAC 100 and the RAS 200, and the RADA performs information synchronization between remote sites, that is, information about UPnP devices located at the local site, And it plays a role to reproduce it as it is.

In addition, the RADA Listener / Relay 111 and 222 are support components of Remote Access Discovery Agents (RADA) 110 and 210, and the CP 130 and the Device 140 are related to remote access Indicates a UPnP CP and a device that do not exist.

In addition, the RAS 200 provides an Inbound Connection Config (221) service for establishing connection request processing from a remote location. At this time, the RATA Config, the RADA Config, and the Inbound Connection Config service are called through a separate management console device 400 located in the house. Also, the home device 300 and the RA management console 400 are connected to the RAS 200 via a LAN.

The RAC 100 is a function required for the remote terminal. The RAS 200 is a function required for the home terminal, and the remote terminal can receive services of UPnP devices located in the home through the connection to the home RAS 200 .

Here, the UPnP devices located in the house inform the RAS 200 of its existence using the SSDP message, and the RAS transmits it to the remote terminal using the RADASync service action such as AddRemoteDevices (). Then, the remote terminal converts the information transmitted through the AddRemoteDevices () service action into an SSDP message and multicasts it to the LAN to which the remote terminal belongs. Through this process, the UPnP devices on the LAN to which the remote terminal belongs can also be provided with the services provided by the UPnP devices on the LAN to which the RAS belongs.

For example, assuming that the LAN to which the remote terminal belongs is the home A and the LAN to which the home terminal belongs is the home B, the UPnP media renderer located in the home A searches the image content of the media server located in the home B, It can be done.

However, when the home addresses A and B are private networks, when the address information of the device of the home A is transferred to the home B, if the same address is used in the home B, an IP address collision problem may occur. A problem arises.

Of course, in RA standard 1.0 technology, it is stated that the connection between the remote terminal and the home where the RAS is located is implemented through a VPN (virtual private network). However, if the VPN is configured, the LAN to which the remote terminal belongs and the LAN to which the RAS belongs are logical And the result is that it consists of one LAN so that the IP conflict between the two LANs can not be solved.

To solve this problem, an application level gateway (ALG) method has been proposed.

According to the ALG method, the 'LOCATION field' of the SSDP message must include URL (uniform resource locator) information. However, when private IP is recorded, the application layer gateway (ALG) process is performed because the URL can not be accessed from the remote site. Specifically, the RAS multicasts the SSDP M-SEARCH message to the home to retrieve the UPnP device. The UPnP device then responds with an HTTP 200 OK message. At this time, if the connection address of the UPnP device included in the HTTP 200 OK message is a private address, the RAS changes the public IP of the RAS to the alternative port information for communication with the remote terminal, thereby preventing a problem such as IP address collision .

However, since the control point is not a UPnP device, the RAS does not respond even if it searches the home UPnP device. Therefore, there is no way to check if there is a control point in the house, so the ALG function can not be applied to the control point.

However, the UPnP device has the function of notifying the control point of an event notifying the change of state in addition to the process of receiving the service call from the control point and transmitting the result of the service call. At this time, prior to the event notification, the control point must register the callback access address for receiving the event to the UPnP device.

However, when the ALG function is not applied to the control point as in the prior art, a problem occurs because the private IP address and the port number are registered as callback access addresses. This is shown in FIG. 2 as follows.

FIG. 2 is a view for explaining a process of receiving an event from a device located at a remote place in a conventional control point.

2, the first UPnP network 500 includes a home gateway 501 having a RAS function, a first UPnP device 503 connected to the home gateway 510 and communicating with the second UPnP device 603, And a control point 505.

The second UPnP network 600 is connected to the home gateway 601 having the RAC function and the home gateway 601 and communicates with the first UPnP device 503 and is connected to the second UPnP Device 603.

In this case, the first UPnP network 500 and the second UPnP network 600 are private networks using private IP addresses.

Here, the control point 505 located in the first UPnP network 500 receives an event reception registration message (SUSCRIBE) including a callback access address generated using a private IP address and a port number, for example, 192.168.1.1 and 9000 ) To the second UPnP device 603.

When the service state change occurs, the second UPnP device 603 tries to connect with the coincide connection addresses included in the event reception registration message (SUSCRIBE), that is, 192.168.1.1 and 9000, to notify the event.

However, because 192.168.1.1 is a private IP address, it is impossible to route packets using the public IP network, so that event notification is not performed.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a control point and a home gateway including a configuration for allowing a control point located in a private network to receive an event from a UPnP device located at a remote location.

According to an aspect of the invention, a control point is provided. The control point is a control point for receiving an event notifying a change in service status from a device located at a remote location. When the control point is assigned private address information, the control point acquires public address information acquired from a home gateway connected to the control point A callback access address for receiving the event; And a transmitter for transmitting an event reception registration message including the callback access address to the device through the home gateway, wherein the device attempts to access the callback access address included in the event reception registration message, Notify.

According to another aspect of the present invention, a home gateway is provided. The apparatus comprises: a home gateway belonging to the first home network supporting remote access between a control point belonging to a first home network and a remote device belonging to a second home network, the home gateway comprising: Wherein the event reception registration message includes a callback access address for receiving an event notifying a change in the status of a service provided by the remote device; a setting unit for setting port forwarding for the callback access address included in the callback access address; A converting unit for changing the callback access address to a public IP address of the home gateway and a port number set by the setting unit; And a transmitting unit for transmitting a callback access address changed by the converting unit to the remote device by including the callback connection address in the event reception registration message, and when the service state change occurs, It tries to connect to the callback connection address and notifies the event.

According to an embodiment of the present invention, a control point located in a private network can normally receive event notification from a remote UPnP device.

1 is a block diagram illustrating a conventional Universal Plug and Play (UPnP) Remote Access Architecture.
FIG. 2 is a view for explaining a problem that occurs in the process of receiving an event from a device located at a remote place in a conventional control point.
3 is a block diagram of a UPnP remote access network according to an embodiment of the present invention.
4 is a flowchart illustrating a process of receiving an event from a device located at a remote location by a control point according to the configuration of FIG.
5 is a block diagram of a UPnP remote access network according to another embodiment of the present invention.
6 is a flowchart illustrating a process of receiving an event from a device located at a remote location by a control point according to the configuration of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

Hereinafter, a control point and a home gateway for receiving an event provided by a device located at a remote location according to an embodiment of the present invention will be described in detail with reference to the drawings.

Here, the present invention can be represented by two embodiments. Figs. 3 and 4 correspond to the first embodiment, and Figs. 5 and 6 correspond to the second embodiment.

≪ Embodiment 1 >

3 is a block diagram of a Universal Plug and Play (UPnP) remote access network according to an embodiment of the present invention.

Referring to FIG. 3, a first universal plug and play (UPnP) network 800 and a second UPnP network 900 communicate over the Internet 1000.

The first UPnP network 800 includes a first home gateway 810 including a function of a remote access server (hereinafter referred to as RAS), a first UPnP device 820, 830 < / RTI >

The second UPnP network 900 includes a second home gateway 910 and a second UPnP device 920 that include the functions of a remote access client (RAC).

Here, the RAS or RAC is a logical device for supporting a remote access service, and is described as a function included in the first home gateway 810 and the second home gateway 910, but may exist as a separate device.

The first UPnP network 800 is an arbitrary home network and the second UPnP network 900 is a remote home network remote from the first UPnP network 800. [

In addition, the first home gateway 810 and the second home gateway 910 support remote connection between the first UPnP network 800 and the second UPnP network 900.

The first home gateway 810 and the second home gateway 910 are connected to the first UPnP device 820 and the second UPnP device 920 existing in the first UPnP network 800 and the second UPnP network 900, And collects and synchronizes information and service information. The first home gateway 810 and the second home gateway 910 form a remote access transport (RAT) channel to transmit and receive remote access information.

At this time, communication between the first home gateway 810 and the second home gateway 910 is performed through a public Internet Protocol address (hereinafter, referred to as an 'IP address'). The first UPnP network 800 and the second UPnP network 900 use an IP-based standard protocol technology and use a private IP address.

Meanwhile, the control point 830 connected to the first home gateway 810 can remotely access the second UPnP device 920 connected to the second home gateway 910 using SOAP (Simple Object Access Protocol). Here, SOAP is a protocol based on XML (eXtensible MarkUp Language) on HTTP (HyperText Transfer Protocol) for remote function call.

At this time, the control point 830 requests subscription for the event information to receive event information informing the state change of the service provided by the second UPnP device 920. Here, the subscription request uses an event reception registration message (SUBSCRIBE).

Such an event reception registration message (SUBSCRIBE) includes a call-back field according to the contents defined in the device architecture v1.1 document of the UPnP forum.

Here, the callback field is a field defined to include a location to which the second UPnP device 920 receiving the event message, i.e., the event reception registration message (SUBSCRIBE), notifies the event. In this callback field, URL (Uniform Resource Locator) information should be specified and the callback access address of the control point 830 is recorded. The callback access address is a URL composed of the IP address and the port number of the control point 830.

Also, the control point 830 receives event information from the second UPnP device 920 using General Event Notification Architecture (GENA).

In detail, the control point 830 includes an assigning unit 831, a memory 832, a determining unit 833, a setting unit 834, a converting unit 835, and a transmitting unit 836.

The assigning unit 831 is assigned an IP address from the first home gateway 810. At this time, the IP address can be automatically allocated by the DHCP (Dynamic Host Configuration Protocol) method.

The memory 832 stores predefined private IP band information. For example, private IP band information defined by an Internet Engineering Task Force (IETF) Request For Comments (RFC) standard.

The determination unit 833 determines whether the IP address allocated by the allocation unit 831 is a private IP address included in the private IP band stored in the memory 832. [

The setting unit 834 requests the first home gateway 810 to set the port forwarding and receives the public IP address of the first home gateway 810 and the external port number set for port forwarding.

The converting unit 835 generates a callback access address using the public IP address of the first home gateway 810 and the port number of the external port number set by the port setting unit 834.

The transmitting unit 836 generates an event reception registration message (SUBSCRIBE) and transmits it to the second UPnP device 920.

Based on the above description, a series of processes in which the control point 830 receives an event provided by the second UPnP device 920 will be described with reference to FIG. In this case, the same reference numerals are used for the same elements as those in Fig.

4 is a flowchart illustrating a process of receiving an event from a device located at a remote location by a control point according to the configuration of FIG.

Referring to FIG. 4, the assigning unit 831 of the control point 830 confirms the IP address allocated from the first home gateway 810 (S101).

The determination unit 833 of the control point 830 determines whether the IP address assigned by the assigning unit 831 is a private IP address included in the private IP band stored in the memory 832 at step S103.

If it is determined that the IP address is not the private IP address, the IP address and the port number allocated by the assigning unit 831 are included in the callback field of the event reception registration message (SUBSCRIBE) (S105), and the second UPnP device 920 (S107).

On the other hand, if it is determined in step S103 that the private IP address is allocated, the setting unit 834 of the control point 830 requests the first home gateway 810 to set the port forwarding (S109).

In step S111, the first home gateway 810 allocates an external port number to the control point 830 requesting port forwarding, and sets forwarding to the private IP address and port number of the control point 830 in step S111. The public IP address of the first home gateway 810 and the external port number set for port forwarding are transmitted to the setting unit 834 (S113).

The converting unit 835 of the control point 830 generates a callback access address using the public IP address of the first home gateway 810 and the port number of the external port that is set by the port forwarding unit 810 received by the setting unit 834 in operation S115. . Then, the transmitting unit 836 of the control point 830 transmits the callback access address generated by the converting unit 835 to the second UPnP device 920 in the callback field of the event reception registration message (SUBSCRIBE) (S117 ).

Then, the second UPnP device 920 notifies the event using the callback access address included in the callback field of the event reception registration message (SUBSCRIBE) received in step S117.

≪ Embodiment 2 >

5 is a block diagram of a UPnP remote access network according to another embodiment of the present invention.

5, the first home gateway 810 'and the control point 830' of the first UPnP network 800 'have substantially the same configuration as that of FIG. Therefore, description of the same components as those of FIG. 3 will be omitted, and the configuration of another embodiment will be described.

Unlike the embodiment of FIG. 3, the control point 830 'generates an event reception registration message (SUBSCRIBE) including a callback connection address generated based on the private IP address and the port number of the control point 830' in the callback field To the second UPnP device 920.

In addition, the first home gateway 810 'receives a SOAP message advertising the location of the second UPnP device 920 from the second home gateway 910.

Here, the 'AddRemoteDevice () message' defined in the RA (Remote Access) standard document of the UPnP forum version 1.0 is used as the SOAP message advertising the location of the second UPnP device 920.

The 'AddRemoteDevice () message' is defined such that a remote terminal addition list, that is, 'DeviceList' is attached as an input parameter and a 'descriptionDocument' item of the 'DeviceList' parameter contains URL information.

In this 'descriptionDocument' item, the connection address of the added remote terminal, that is, the second UPnP device 920 is recorded.

Upon receiving the 'AddRemoteDevice () message', the first home gateway 810 'generates a Simple Service Discovery Protocol (SSDP) message including the connection address of the second UPnP device 920 and transmits the SSDP message to the control point 830' send. This SSDP message serves to process the control point 830 'so that it can discover the second UPnP device 920 on the remote network.

In addition, the control point 830 'transmits an event reception registration message (SUBSCRIBE) to the second UPnP device 920 through the first home gateway 810'.

The first home gateway 810 'includes a receiving unit 811, an extracting unit 812, a packet filter 813, a setting unit 814, a converting unit 815, and a transmitting unit 816.

The receiving unit 811 receives the SSDP message or the SOAP message from the first UPnP device 820, the control point 830 'and the second home gateway 910.

The extractor 812 extracts an 'AddRemoteDevice () message' that advertises the location of the second UPnP device 920 among the messages received by the receiver 811.

The packet filter 813 extracts the connection address of the second UPnP device 920 included in the 'descriptionDocument' item of the 'AddRemoteDevice () message' when the 'AddRemoteDevice () And set packet filtering to intercept the transmitted packet by setting the connected address as the destination address.

The packet filter 813 then selects an event reception registration message (SUBSCRIBE) from among the filtered packets.

The setting unit 814 extracts the callback access address from the callback field of the event reception registration message (SUBSCRIBE) filtered by the packet filter 813 to set up the port forwarding. That is, an external port number is assigned to the callback connection address, and forwarding to the callback connection address is set.

The conversion unit 815 converts the callback access address extracted from the callback field of the event reception registration message SUBSCRIBE filtered by the packet filter 813 into the public IP address of the first home gateway 810 ' Forwarding Change to the external port number set.

The transmitting unit 816 transmits an event reception registration message (SUBSCRIBE) whose callback access address is changed by the converting unit 815 to the second UPnP device 920.

Based on the above description, a series of processes in which the control point 830 'receives an event provided by the second UPnP device 920 will be described with reference to FIG. 5 are denoted by the same reference numerals.

6 is a flowchart illustrating a process of receiving an event from a device located at a remote location by a control point according to the configuration of FIG.

Referring to FIG. 6, when the second UPnP device 920 is added to the second UPnP network 900, the second UPnP device 920 transmits an SSDP Alive message to the second home gateway 910 (S201). Then, the second home gateway 910 transmits' AddRemoteDevice () message 'including the connection address of the second UPnP device 920 to the first home gateway 810' (S203).

When the extracting unit 812 of the first home gateway 810 'extracts the' AddRemoteDevice () message 'from the messages received by the receiving unit 811 of the first home gateway 810', the first home gateway 810 ' The packet filter 813 of the addRemoteDevice () message extracts the connection address from the 'descriptionDocument' item of the 'AddRemoteDevice () message (S205) and sets the extracted connection address as the destination to set packet filtering for intercepting the transmitted packet S207).

Thereafter, the packet filter 813 selects an event reception registration message (SUBSCRIBE) from among the filtered packets (S209).

Subsequently, the setting unit 814 extracts a callback connection address from the callback connection field of the event reception registration message (SUBSCRIBE) acquired through the packet filter 813 (S213). Then, port forwarding is set for the callback access address (S215). That is, an arbitrary external port number, and sets the assigned external port number to the internal IP address and port number of the control point 830 '.

At this time, the internal IP address and the port number refer to the private IP address and port number of the control point 830 '.

Then, the converting unit 815 of the first home gateway 810 'changes the callback access address extracted in step S213 to the public IP address of the first home gateway 810' and the external port number set for port forwarding in step S215 (S217).

The transmitting unit 816 of the first home gateway 810 'includes the callback access address changed in step S217 in the callback field of the event reception registration message (SUBSCRIBE) received in step S209 and transmits it to the second UPnP device 920 (S219).

Then, the second UPnP device 920 notifies the event using the callback access address included in the callback field of the event reception registration message (SUBSCRIBE) received in step S219.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

100: Remote Access Client 110: RADA
111: RADA Listener / Relay 112: RADASync
113: RADASync CP 120: RAC
121: RATAConfig 130: CP
140: Device 150: RA Transport Agent
200: Remote Access Server 210: RADA
211: RADASync 212: RADASync CP
220: RAS 221: Inbound Connection Config
222: RADA Listener / Relay 223: RADAConfig
224: RATAConfig 230: RA Transport Agent
300: Home Device 400: RA Management Console
500: first UPnP network 501: home gateway (RAS)
503: first UPnP device 505: control point
600: second UPnP network 601: home gateway (RAC)
603: Second UPnP device 700: Internet network
800: first UPnP network 810, 810 ': first home gateway
811: Receiving unit 812:
813: Packet filter 814: Setting unit
815: conversion unit 816:
820: first UPnP device 830, 830 ': control point
831: Assignment unit 832: Memory
833: Judgment section 834: Setting section
835: Conversion section 836: Transmission section
900: second UPnP network 910: second home gateway (RAC)
920: second UPnP device 1000: Internet network

Claims (7)

There is provided a control point for receiving an event notifying a state change of a service from a device located at a remote location,
A conversion unit for changing a callback access address for receiving the event using the public address information requested by the home gateway when the control point is allocated with private address information from a home gateway connected to the control point; And
And a transmitting unit for transmitting an event reception registration message including the changed callback access address to the device through the home gateway,
Wherein the device attempts to connect to the changed callback access address included in the event reception registration message to notify the event. The method according to claim 1,
Further comprising a setting unit for requesting the home gateway to set a port forwarding and receiving a public IP address of the home gateway and an external port number set for port forwarding,
Wherein,
And a control point for changing the callback access address using the public IP address and the external port number received by the setting unit. 3. The method according to claim 1 or 2,
Wherein,
(Uniform resource locator) information specified in a CALLBACK field of the event reception registration message defined in the universal plug and play service using the public IP address and the port number Control points feature. A home gateway belonging to the first home network supporting remote access between a control point belonging to a first home network and a remote device belonging to a second home network,
Wherein the event reception registration message includes a callback access address for receiving an event notifying a change in status of a service provided by the remote device, A setting unit for setting the setting value;
A conversion unit for changing the callback access address to a public IP address of the home gateway and an external port number set by the setting unit for port forwarding; And
And a transmitting unit for transmitting the event reception registration message including the changed callback connection address to the remote device,
Wherein the remote device attempts to connect to the changed callback access address included in the event reception registration message and notifies the event when the service state change occurs. 5. The method of claim 4,
Further comprising: a packet filter configured to set packet filtering for intercepting a packet having a connection address of the remote device set as a destination, and to select the event reception registration message from the filtered packets. 6. The method of claim 5,
The packet filter includes:
A home gateway for extracting URL (uniform resource locator) information included in a descriptionDocument item of the SOAP message to set packet filtering when a Simple Object Access Protocol (SOAP) message for advertising its location is received from the remote device. 5. The method of claim 4,
Wherein,
The URL information specified in the CALLBACK field of the event reception registration message defined in the universal plug and play service is transmitted to the home gateway using public IP address information of the home gateway and the external port number set by the port forwarding To the home gateway.

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