KR20040039039A - Control message multicasting method and apparatus for universal plug and play network system - Google Patents

Abstract

PURPOSE: A method for multicasting a control message of a UPnP(Universal Plug and Play)-based network system and a device therefor are provided to include SOAP(Simple Object Access Protocol)/HTTPMU/UDP functions in a UPnP device architecture 1.0 specification, and to simultaneously transmit the same control message to many devices of a UPnP network, thereby improving performance. CONSTITUTION: A UPnP-based network system determines a control message to be multicasted. The UPnP-based network system obtains a transmission protocol and a data format supported by a media server. The UPnP-based network system obtains a protocol and a data format supported by a media renderer. The UPnP-based network system determines a transmission protocol and a data format to be multicasted in reference to the obtained transmission protocols and the data formats, and multicasts the control message to many devices by reflecting the determined transmission protocol and the data format.

Description

CONTROL MESSAGE MULTICASTING METHOD AND APPARATUS FOR UNIVERSAL PLUG AND PLAY NETWORK SYSTEM}

The present invention relates to UPnP-based networking technology, and more particularly, to a method and apparatus for multicasting control message.

The communication between two or more devices in a home is also called a home network.

Currently, home networks used in homes are connected to various PCs and PCs due to the expansion of the Internet and the development of digital technology. There is a network, and in recent years, networks for controlling home appliances and security devices are actively developed and distributed.

UPnP (Universal Plug and Play) has been proposed as an attempt to integrate networks in current homes.

UPnP is a defacto industry standard that many companies have created and built on the UPnP forum (http://www.upnp.org).

As illustrated in the configuration diagram of FIG. 1, the UPnP network includes a control point for controlling a device and a plurality of devices for providing a service.

Accordingly, since the control point provides a user interface, the user can input a command to the control point through the user interface to find (discovery, description) and control various devices.

In addition, since the control point and the device are configured using the IP protocol, even if the data network, the AV network and the control network in the home communicate using different physical media, it is possible to integrate them into one network if only IP is supported. Do.

In the current UPnP AV 1.0 standard, the UPnP AV structure means that the Control Point (CP) is configured separately from the Media Server (MS), Media Renderer (MR), or on the Media Server (MS) or Media Renderer (MR). It is provided and configured.

In addition, the current UPnP device architecture version 1.0 uses Internet protocols such as TCP / IP and HTTP, and technologies such as eXtensible Markup Language (XML) and Simple Object Access Protocol (SOAP).

That is, the protocol stack structure for configuring the UPnP network includes a network layer 211 including IP and a transport layer including UDP and TCP, as shown in the exemplary diagram of FIG. 2. 212 and presentation / session including technologies such as HTTP, eXtensible Markup Language (XML), Simple Object Access Protocol (SOAP), Simple Service Discovery Protocol (SSDP), and technologies such as Generic Event Notification Architecture (GENA). It is composed of a layer (Presentation / Session Layer) 213, and an Application Layer (214) including related information such as UPnP devices, forums (ForumP), operators.

In the UPnP network system using the UPnP protocol stack, communication between a control point (hereinafter, abbreviated as CP) and a device is defined in six steps as follows.

(One). Addressing step where devices are assigned IP addresses

(2). Discovery step where CPs discover the device's presence

(3). Description step in which the CP obtains the device and service information supported by the device

(4). Control phase in which the CP calls a device service

(5). Eventing stage in which the device notifies the CP of its state transition

(6). Presentation stage in which the device shows its status and control information

Thus, by using the functions defined above, the user can configure a home network without complicated network settings.

When a UPnP device joins a network, it receives its IP address using Dynamic Host Configuration Protocol (DHCP) or, if there is no DHCP server in the network, uses the automatic IP function to randomly configure IP within a specific subnet to It is used after checking whether or not duplicate usage of. This is called addressing.

The discovery step is a process in which CPs find UPnP devices in a network, using a simple service discovery protocol (SSDP).

If the device is added to the network, the device delivers an SSD (alive) message to the network using the IP multicast function and the CP receives the appearance message and can know whether the device exists.

In addition, when the CP joins the network newly, the CP multicasts an SSD-search message (m-search) message to the network, and UPnP devices confirming the search message send a response message containing their information to the CP. do.

In addition, the CP checks the response message and, if desired, may request the device for detailed information related to the device, and the received device sends its information as an XML document. This process is called a description.

If the CP wants to control an arbitrary device, a desired service is sent to the device using SOAP based on the device description. SOAP is a protocol written in XML over HTTP for the purpose of remote function calls.

Finally, if the device wants to receive an event message, the CP sends a subscription request for the event to the device. If the subscription is successful, the device sends an event message to the CP using GENA.

However, the current UPnP device architecture 1.0 specification assumes one Control Point (CP) per network, so that the CP can access each device sequentially even if the CP transmits the same control message to multiple devices. : 1 There is a problem to communicate.

That is, according to the current UPnP device architecture 1.0 specification, the protocol for control is defined to use SOAP / HTTP / TCP. Therefore, it is impossible to simultaneously transmit control messages to multiple devices.

Therefore, the present invention proposes a protocol for transmitting the same control message to multiple devices at the same time in order to improve the conventional problems, thereby reducing the hassle of CP (control point) accessing each device to transmit 1: 1 commands. An object of the present invention is to provide a method and apparatus for multicasting control messages of a UPnP-based network system.

1 is a block diagram of a general UPnP network.

Figure 2 is an exemplary view showing the structure of the UPnP protocol stack.

3 is an exemplary view showing the structure of a protocol stack of the present invention.

4 is a block diagram of a control point (CP) in an embodiment of the present invention.

FIG. 5 is a configuration diagram of the entire list storage unit in FIG. 4; FIG.

6 is a configuration diagram of a group list storage unit in FIG. 4;

7 is a flowchart illustrating a control message multicast process in an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

410: CP function unit 420: address management unit

430: Full list storage unit 440: Group list storage unit

The present invention is a protocol stack structure defined in the UPnP device architecture 1.0 specification to achieve the above object, characterized in that configured to transmit the same control message to multiple devices at the same time including a SOAP / HTTPMU layer over the UDP layer do.

In addition, the present invention is to determine the control message (Content) to be multicast from the media server (MS) in order to achieve the above object, obtaining a transport protocol and data format supported by the media server, the media renderer Acquiring a protocol and a data format supported by the MS; determining a transmission protocol and a data format to multicast with reference to the obtained transmission protocol and data format, and reflecting the determined transmission protocol and data format to a plurality of devices. And multicasting the same control message.

In order to achieve the above steps, the present invention provides a full list storage unit for storing a plurality of device lists existing on a UPnP network, and devices supporting the same transport protocol and data format for multiple devices existing on a UPnP network. A group list storage unit for storing a group list grouped by group, a CP (Control Point) function unit for detecting and controlling a plurality of devices, and an entire list or a group list by control of the CP function unit A control point (CP) is configured by including an address manager for multicasting control messages to a plurality of devices.

The control message is configured by the M-POST method including a group path setting syntax, a content setting syntax (length, type), and a SOAP setting syntax.

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

3 is a structural diagram of a protocol stack for an embodiment of the present invention, as shown here, a network layer including IP, a transport layer including UDP and TCP, HTTP, It is composed of Presentation / Session Layer including protocols such as XML, SOAP, SSDP, and technologies such as GENA, and Application Layer including related information such as UPnP devices, forums and operators. Based on the protocol stack structure, SOAP / HTTPMU is configured on the presentation / session layer over UDP to simultaneously transmit the same control message to multiple devices.

That is, the present invention instructs the media server (hereinafter abbreviated as MS) to join the multicasting group as a media renderer (hereinafter abbreviated as MS) in the AV device of the UPnP device architecture 1.0 specification. Commands like CM :: GetProtocolInfo () or CM :: PrepareForconnection can be sent to all media renderers individually to define multiple devices by defining HTTPMU over UDP and SOAP over that HTTPMU to minimize the hassle of receiving responses. This allows multicasting the same control message.

4 is a configuration diagram of a control point (CP) proposed in the embodiment of the present invention, as shown in this, a full list storage unit 430 for storing a list of all devices existing on the UPnP network, and UPnP network A group list storage unit 440 that stores a group list grouping a plurality of devices existing in the device according to devices supporting the same transmission protocol and data format, and a function of detecting and controlling a plurality of devices existing in the UPnP network. The CP function unit 410 for performing the operation and the list stored in the entire list storage unit 430 or the second list storage unit 440 under the control of the CP function unit 410, and the plurality of And an address manager 420 for transmitting a control message to the device.

The full list storage unit 430 is configured to store a path of control URL and a host of control URL: port of control URL for all devices, as shown in the exemplary diagram of FIG. 5.

The group list storage unit 440 is configured to classify and store a path of control URL and a host of control URL: port control URL having the same transmission protocol and data format, as shown in the example of FIG. 6. do.

Referring to the operation and effect of the embodiment of the present invention configured as described above are as follows.

First, the CP function unit 410, which performs the same function as the CP (Control Point) defined in the UPnP device architecture 1.0 specification, has content to be multicasted through the ContentDirectory :: Browse () or ContentDirectory :: Search () action of the MS. content is determined, and the transfer protocol and data format provided by the MS for transmitting content to the home network are obtained.

Thereafter, the CP function unit 410 obtains a protocol and data format supported by the MR.

Accordingly, the CP function unit 410 determines the protocol and data format supported by both by referring to the protocol and data format obtained from the MS and MR. In this case, the CP function unit 410 classifies device groups that support the same transmission protocol and data format by referring to the values stored in the entire list storage unit 430 and the group list storage unit 440.

Thereafter, when the CP function unit 410 determines the transmission protocol and the data format, the CP function unit 440 controls the address manager 440 to multicast the control message only to a plurality of devices belonging to the corresponding group. The address manager 440 multicasts the same control message to a plurality of devices existing on the UPnP network using UDP / HTTPMU / SOAP.

In addition, when multicasting a control message, the CP function unit 410 selects one of three types of addresses, as shown in the operation flowchart of FIG.

That is, assuming that there are currently N MRs on the UPnP network, 1) when all the control messages are transmitted to N MRs, and 2) when the control messages are transmitted to M MRs among N MRs, one last. This is the case where control message is transmitted to MR.

In order to simultaneously deliver the content of the MS to a plurality of MRs, the CP function 410 needs to know a transfer protocol and a data format provided by each MR. However, when using a specific path of control URL and a host of control URL: port of control URL, "*" is used for the group setting part because multicasting of the same content is not possible. Here, * means that a specific resource (for example, a control URL or a port part of a control URL) is not defined.

The address management unit 420 received from the CP function unit 410, the XML file created by the M-POST method as described below, confirms that the group path is set to "*" and is stored in the entire list storage unit 430. Copy the path of control URL and the host of control URL: port control URL and request the CM :: GetProtocolInfo () action from all devices on the UPnP network using HTTPMU / UDP.

Then, when a response arrives from each device, the address manager 420 determines a new path of control URL and a host of control URL: port control URL by grouping those having the same transmission protocol and data format and assigning them to each group. .

For example, to form a connection with the first group of devices 1, 5, and 7 of FIG. 6, the CP function unit 410 searches the entire list storage unit 430 and sets the path of control URL as AA, and the host of control URL: port Sets the control URL to AA '*: 2000 and transmits a request for the CM :: PrepareForconnection action to the address manager 420.

Accordingly, the address manager 420 searches the entire list storage unit 430 to determine the path of control URL and the host of control URL of the devices 1, 5, and 7 corresponding to AA and AA ′: 2000. Copy and multicast using HTTPMU / UDP. In other words, in case of transmitting control message to a specific group, XML file is created by M-POST method as below.

In addition, when sending a control message to one MR, the CP function unit 410 transmits a path of control URL and a host of control URL: port of control URL defined in the UPnP device architecture 1.0 specification to the address manager 420. Accordingly, the address manager 420 searches the group list storage 440 to confirm that there is no assigned path of control URL and host of control URL: port of control URL, and then the path of control transmitted by the CP function unit 410. URL and host of control URL: Forward the port of control URL to the device using HTTP / TCP. In this case, the delivered XML file is as follows.

As described in detail above, the present invention allows each device and 1 device in the prior art to simultaneously transmit the same control message to multiple devices existing on the UPnP network, including SOAP / HTTPMU / UDP in the UPnP device architecture 1.0 specification. The performance can be improved by eliminating the hassle of transmitting the same control message through the: 1 communication.

Claims (7)

In the protocol stack structure defined in the UPnP-based network, Method for multicasting control messages in a UPnP-based network system, characterized in that configured to transmit the same control message to multiple devices at the same time including the HTTPMU / SOAP layer on the UDP layer. In the message transmission method of the UPnP-based network system, Determining a control message (Content) to be multicasted; Obtaining a transmission protocol and a data format supported by the media server; Obtaining a protocol and a data format supported by the media renderer; Determining a transmission protocol and a data format to multicast with reference to the obtained transmission protocol and data format, and performing a fourth step of multicasting a control message to a plurality of devices by reflecting the determined transmission protocol and data format A control message multicast method for UPnP based network systems. The method of claim 2, wherein the fourth step is Multicasting a control message by reflecting each path value corresponding to all devices present on the UPnP network; The process consists of identifying the devices in the group with the same transmission protocol and data format among all devices on the UPnP network and multicasting the control message only to the devices in the group by reflecting the path value corresponding to the device. A control message multicast method for UPnP based network systems. The method of claim 2, wherein the fourth step is Multicasting a control message to all devices by referring to a value of a path corresponding to each device existing on the UPnP network; If there is a response to the multicasted control message, it is a process of identifying a device of a group having the same transport protocol and data format and multicasting the control message only to the devices of the group by referring to a path value corresponding to the device. A control message multicast method of a UPnP based network system, characterized in that the. The method according to any one of claims 2 to 4, wherein the multicast scheme is A control message multicast method of a UPnP based network system, characterized by using SOAP / HTTPMU / UDP. In the UPnP-based network system having a control point (CP), a media server (Media Server) and a media renderer (MediaRenderer), CP is An entire list storage unit for storing a plurality of device lists existing on the UPnP network, A group list storage unit for storing a group list grouping a plurality of devices existing in the UPnP network by devices supporting the same transport protocol and data format; CP (Control Point) function to perform a function of detecting and controlling a plurality of devices, Multi-control message of UPnP-based network system, characterized by comprising an address manager for multicasting the control message to a plurality of devices by referring to the entire list or the group list by the control of the CP function unit Cast device. The method of claim 6 wherein the control message is Control message multicast device of UPnP-based network system, comprising M-POST method including group path setting syntax, content setting syntax (length, type) and SOAP setting syntax.