DE10301222A1 - Method for processing messages to be transmitted via a transmission medium in a network of distributed stations, and network station - Google Patents

Abstract

The invention relates to a method for processing messages distributed over a transmission medium in a network. In a home network in which the devices are designed according to the HAVi standard, it is provided that when a HAVi message is sent to another network device, the message must be confirmed within a maximum timeout of 30 seconds. Only after this time has elapsed can the non-responding network station be deleted from the list of active network devices. This can lead to a significant speed reduction at the station initiating the message transmission. According to the invention, the response behavior of the transmitting station is improved in that a message transmission is started with a shorter timeout, e.g. B. two seconds, and, if this timeout was exceeded, the component leaving the message transmission is immediately released again for further processing. A waiting process then runs in the background, in which it is checked whether the confirmation message for the message is still arriving within the 30 second timeout. If not, the non-responding network subscriber station is deleted from the list of active HAVi devices. DOLLAR A Alternatively, instead of the waiting process working in the background, an activity check message is sent to the non-responding device with the 30 second timeout and ...

Description

The invention relates to the technical Area of the so-called home networks. A technique in particular with the availability a network station after transmission a message to an inactive station can be improved.

Background of the Invention

In the future, consumer electronics devices Various manufacturers in-house or at home with each other be networked. A powerful one Datenübertragungsprotokol is already available with the IEEE 1394 bus protocol. According to this Bus protocol, data packets are transmitted serially between the network subscriber stations. The data transmission capacity is 100 Mbps and more. about such bus connections can thus also conveniently transmit video and audio data streams in real time become. The associated Bus protocol is specified in the IEEE 1394 standard. For the transfer of audio and video streams (isochronous data transmission) there is a separate specification according to the IEC 61883 standard Available. In the IEEE 1394 standard, however, only the lower layers (physical Layer, data link layer, as well as parts of the transaction or network Layers) of the OSI / ISO reference model of data communication. The additional standard IEC 61883 specifies this also the so-called transport layer. The ones above Layers namely Session layer, presentation layer and application layer are thus still undefined.

To the real goal of networking of devices to reach different manufacturers in the home area A consortium of companies made this the remaining ones Standardize layers in the OSI reference model. The result of this work is the so-called HAVi specification, which meanwhile Version 1.1 is available. The exact title is: Specification of the Home Audio / Video interoparability (HAVi) architecture, version 1.1, May 15, 2001. An essential part of the HAVi specification concerns the standardization of messages for data exchange. There are a series of standardized messages that the HAVi devices know and can implement have to.

invention

The inventor is within his development activity when implementing the HAVi specification for consumer electronics devices to the following Encountered problem. According to the HAVi specification, there is a standardized HAVi message with a so-called timeout for the reply transmitted to an addressed device. According to HAVi specification is a HAVi message from the device receiving the message to confirm. In the case of a request message, the message is received first immediate confirmation and subsequently the actual response with variable time intervals. So that a station, the one to a faulty one that is no longer available in the network Device addressed HAVi message has not sent endlessly to the reply or the confirmation message waits, has been defined in the HAVi specification that at Sending a Havi message in the device sending the message, a so-called Monitored timeout must become. This is the maximum duration, so to speak by when the HAVi message sent is at least confirmed got to. In the HAVi specification the maximum timeout 30s. Will be up to 30s after sending the message no confirmation received, the device sending the message should not more on a confirmation or the reply wait, and you are allowed to remove the previously addressed device from its List of active HAVi devices to delete. This list is in the local Communication Media Manager of the respective HAVi device.

With this definition of the timeout the response behavior of a HAVi device is not optimal. If e.g. the operator uses the remote control to issue a start command for one Sends video recorder to the TV in front of him, then according to the HAVi specification the TV set generate a corresponding HAVi message and use the Home network to that somewhere else in the room or in another VCR installed in the room. If the VCR is one Malfunction, so should the TV set Send the HAVi message for Wait 30 seconds for the start command before issuing a command Error message. The operator would have so not immediate feedback about the problem that has occurred and does not know why the one previously sent Start command not executed becomes. The operator would be during this Time in the dark as to whether the problem is with the VCR or maybe even on the TV, because this does not seem to respond immediately to the commands sent. Even if the operator does not assume an error would come to the scenario described to a significant reduction in the TV speed.

A possible solution to this problem would be to use a shorter timeout when sending HAVi messages, which is permitted in principle in the HAVi standard. For example, one could implement that every device in the network must respond within two seconds. If the response does not come within this time, the response would no longer be waited for and the actual application of the requesting device released. This reduced timeout would result in a reduction in the number of defective devices in the network operating speed remain within acceptable limits. Nevertheless, this solution has the disadvantage that this reduced operating speed with a 2s time delay persists as long as the device is still available in the network. Because according to the HAVi standard, a device may only be removed from the list of active HAVi devices in the network if it has not returned a confirmation message after a request with a timeout of 30 s. This is where the HAVi standard is laid down and no deviating implementation is allowed at this point, because otherwise the device would be incompatible with the HAVi standard.

The invention has the object of this previously mentioned improve problematic behavior of a network device. Solutions according to the invention are in the independent claims 1, 2 and 7 and 8. Also in the devices according to the invention for the Communication with other HAVi devices a shortened timeout from e.g. 2s can be used. Since after this time it was not clear is whether an answer might have come after all (maybe after another 100ms) or whether the answer is actually not will come within the 30s timeout specified by HAVi the device after two seconds without result, not out of List of active HAVi devices be removed.

According to a first solution modified the messaging system of the HAVi device so that the calling software component after the elapsed timeout (e.g. 2s) gets the message that no response from the addressed Device arrived is. This message causes the calling software component is released. So it is no longer blocked. It will a recognizable reaction for the operator can already be seen after 2s. Furthermore should the messaging system continues to respond to the answer of the addressed device waiting. If this answer arrives before the 30s limit (this is synonymous with the fact that the device is still functional, however, the requesting device just didn't wait long enough) the messaging system ends waiting without further consequences. However, it is always after 30s If no response has been received, the addressed device will then automatically removed from the messaging system from the list of active HAVi devices.

A second solution according to the invention is based on that an additional Software component e.g. is developed as part of the messaging system, the addressed devices check for correct functioning. comes it to the case described above that the addressed device is not on the network within the briefly set timeout of e.g. 2s answered has, this will be additional Component called. This can be activated automatically by the Messaging system happen. This additional component is now sending an activity review message with the maximum timeout of 30s to the problematic device. Becomes no confirmation message upon request received within the 30s timeout, the problematic becomes again Device off the list of active HAVi devices away.

Both solutions offer the advantage that reducing the speed of the requesting HAVi device is limited to a short, acceptable period of time. After that works this HAVi device again at full speed, even if the problematic Device still located in the network. In addition, a defective device will ultimately but removed after 30 seconds from the list of active HAVi devices and it cannot in the future for further speed-reducing requests to this device.

Through the measures listed in the dependent claims advantageous further developments and improvements are possible.

The measures according to the invention are corresponding Form in the independent claims 7 and 8 regarding a network station according to the invention listed.

drawings

The invention is described below of drawings closer explained. These show in

1 an example of a simple home network;

2 according to the display of the network structure on the display of the television in the network 1 ;

3 according to the display of an operating menu for the video recorder on the display of the television in the network 1 ;

4 issuing an error message on the display of the television set in response to the absence of a confirmation message upon request to the video recorder;

5 the display of the new network structure after the video recorder has been deleted from the list of active network devices;

6 the interaction of the software components of the TV set and video recorder when a HAVi message is sent from the TV set to the video recorder;

7 the interaction of the software components in the TV set when a HAVi message is sent to the video recorder, if the VCR does not send back a confirmation message or a response according to a first exemplary embodiment of the invention;

8th the interaction of the software components of a TV set when sending a HAVi message to the video recorder, if the latter does not send the confirmation message or the reply back according to a second version Example of the invention.

Embodiments of the invention

A very simple home network is in the 1 shown. This consists of only three network subscriber stations. The reference symbol DTV denotes a digital television set. Connected to it is a digital video recorder DVR and a digital satellite receiver DSAT. A commercially available DVHS device is mentioned as an example of a digital video recorder. However, a recording device designed for the description of optical disks or a hard disk recorder could also be used. A commercially available DVB satellite receiver is mentioned as an example of a digital satellite receiver. Both devices are connected to the DTV digital television via separate IEEE 1394 bus cables.

2 shows the representation of the network structure on the display of the digital television DTV. In this display the network structure is according to 1 reflected. Such a display practically corresponds to a kind of main menu for the operation of devices in the network. Using the cursor control buttons on the remote control, the operator can select one of the devices shown. The outline of the DVR video recorder shown is intended to indicate that the operator has selected the video recorder using the cursor control keys. This is indicated in the display, for example by highlighting the video recorder. After pressing the OK button on the remote control, the display changes and shows an operating menu for the selected video recorder. A simple example of such an operating menu is in the 3 shown. In

3 only the main functions, Play, Fastforward, Fastreverse, Stop, Recording, Pause are displayed. Again, the operator can select a displayed function using the cursor control keys and call it up with the OK key. In 3 the symbol for the play function is outlined. This is to indicate that the operator has selected the playback function and that the video recorder is to play the inserted tape.

4 now shows the response to this function call. After two seconds, for example, the display changes to that in 4 shown ad. It was assumed that the video recorder did not send a confirmation message within the two second waiting time. The timeout set to two seconds for the HAVi message that the play command transmits was therefore exceeded, which leads to the display returning to the main menu with the network structure being displayed and an error message being output for the video recorder at the same time. According to the representation of the network structure 4 the symbol for the DVR video recorder is also roughly hatched, which is intended to indicate that this component has shown problematic behavior.

5 then still shows the display on the TV set after the full 30s HAVi timeout without returning a confirmation or reply message. In this case, the display in the main menu changes in such a way that only the television DTV and the satellite receiver DSAT are shown in the network structure. This is to make it clear that the video recorder is no longer one of the active HAVi devices.

In 6 are the components of the so-called HAVi stack for the devices in the network 1 shown. In the example, it is assumed that all devices in the network support level 1 interoperability in accordance with the HAVi standard. For this purpose, each network device is equipped with a so-called embedded DCM (Device Control Module). 6 shows the components of the TV set in the middle, the components of the digital satellite receiver DSAT on the left and the software components of the DVA video recorder on the right.

The DCM of a network device is practical an interface for controlling the functions of the device. in the HAVi standards are for certain device types the DCM functionalities already have been defined. These are a tuner DCM, a clock DCM, one Camera DCM, an AV Disc DCM, an amplifier DCM, a display DCM, an AV display DCM, a modem DCM as well a web proxy DCM. There is therefore one in the digital satellite receiver DSAT HAVi standard tuner DCM implemented. An AV display DCM was installed in the digital TV set DTV implemented. A VCR-DCM is implemented in the DVR video recorder.

The HAVi standard differentiates between different classes of devices. These are so-called Full AV Devices (FAV devices), Intermediate AV Devices (IAV devices), Base AV Devices (BAV devices) and Legacy AV Devices (LAV devices). Of these device classes, only the devices of the last class, the LAV devices, are already existing consumer electronics devices that are not designed according to the HAVi standard. All other devices are already designed according to the HAVi standard. The FAV devices have the largest range of functions and the broadest support of the HAVi standard. The special feature of the FAV devices is that they provide a runtime environment for Java byte code. This enables a FAV device to load Java byte code from other devices and thus create an expanded option for their control. Typical examples of FAV devices are digital TV sets, but also set-top boxes or also PCs.

The class of IAV devices is through a restricted Features and limited resource options marked. They do not offer a runtime environment for Java byte code and therefore cannot be used as a control device for any other equipment serve in the home network. But you can support predefined functions of certain devices and therefore also to a limited extent equipment check in the home network.

The BAV devices offer even less functionality and have no HAVi stack. You cannot control other devices in the home network yourself. However, they have Java byte code with which they are controlled by a FAV device or IAV device can.

In the example according to 6 the digital television DTV is designed as a FAV device, the digital video recorder belongs to the class of IAV devices and the digital satellite receiver DSAT is also designed as an IAV device. The other software components of the devices are in the devices digital satellite receiver DSAT and digital video recorder DVR in 6 only hinted at, but agree with the corresponding software components of the digital TV set DTV. The software elements are an Event Manager EMGR, a Registry REG, a DCM Manager DCMMGR, a Resource Manager RMGR, a Stream Manager SMGR, a Messaging System MSYS and a Communication Media Manager CMM. Another component IEEE 1394 is shown below the software component CMM. However, this is not necessarily to be regarded as a software component. This component is only intended to indicate that an interface for the 1394 bus protocol is also present in each device. Today, the IEEE 1394 bus protocol is usually implemented in hardware using a 1394 physical layer IC and a 1394 data link layer IC. This component is therefore separated from the other software components by a dashed line.

Because the software components presented so far all of which are known from the HAVi standard, will only be mentioned in the following to the extent that they are dealt with as to understand the Invention is required. The Event Manager EMGR serves as an event management unit. An event is a change in the status of a device or of an object or the entire home network. The registry REG contains a list of the existing software elements. The DCM Manager is responsible for the installation and removal of DCM code units for FAV and IAV devices. As part of the level 1 interoperability implemented here, the DCM manager must not necessarily be there. The resource manager RMGR manages the resources of the respective device. The Stream Manager SMGR is responsible for real-time AV data transmission between the devices an established AV connection. The messaging system is MSYS responsible for forwarding the messages received or to be sent to the respective devices. There is an abundance in the HAVi standard specified by standardized HAVi messages. The communication standardized HAVi messages are not only used across devices instead of. Also internally in one device standardized HAVI messages between different Objects exchanged. For this purpose, the individual objects are appropriate Addresses assigned to SEID. With the software component Communication Media Manager CMM supports asynchronous data transfer via the 1394 bus. Here is also lists the active HAVi devices.

As a further software component is on the digital TV DTV also provided a so-called user interface UI. This corresponds to an application program that the screen structure according to the the operator requests commands and also the associated messages via the Messaging System MSYS to other devices or the DCM of your own device.

6 now shows the typical sequence of a control process of a network device via the user interface of the digital television set DTV. For this purpose, it is assumed that the operator on the remote control sends an operating request during the ongoing transmission of AV data from the video recorder DVR to the display device DTV. Usually, a universal remote control will be available in a home network with which several devices can be controlled. The operator then presses the corresponding VCR button on the remote control to operate the DVR video recorder. The user interface UI of the television set DTV will then generate a corresponding message to the messaging system MSYS.

In 6 the sending of this message to the MSYS messaging system is marked with the mark ➀. The messaging system MSYS of the television set DTV will then send an operating request message to the video recorder DVR. This message is then transmitted via the 1394 interface from the television set DTV and video recorder DVR to the messaging system MSYS of the video recorder DVR. The corresponding message transmission is in 6 marked with the mark ➁. After receipt of this operating request message, provided that an active video recorder DVR is used, the next thing to do is send a confirmation message back to the messaging system MSYS of the television set DTV. This retransmission of the confirmation message is in 6 marked with the mark ➂. Furthermore, the messaging system of the DVR video recorder immediately receives a corresponding notification of the VCR DCM in the video recorder make DVR. This notification is in 6 marked with the mark ➃. The VCR DCM will then deliver its control functions to the MSYS messaging system of the DVR video recorder, which in turn transmits this operating information back to the MSYS messaging system of the TV set DTV in standardized HAVi messages. The corresponding steps are in 6 provided with the time stamps ➄ and ➅. Finally, the messaging system MSYS of the television set will provide the feedback to the user interface UI, which generates the associated display elements on the display of the television set DTV. This last transmission is in 6 marked with the mark ➆.

In 7 the case is now shown that the operator issues the control command PLAY for the video recorder DVR according to the 3 , The user interface UI converts this operating request into a corresponding message for the messaging system MSYS of the television set DTV. The HAVi message generated by the messaging system of the television set DTV is then transmitted to the video recorder via the IEEE 1394 interface in step ➁, but is not forwarded there to the higher software elements because the video recorder malfunctions. Since the HAVi message in step ➁ was sent with a timeout of, for example, 2s, the messaging system MSYS of the television set DTV will, according to the invention, notify the user interface after the 2s have elapsed, thereby releasing the user interface, but at the same time prompting an error message to be issued will, as in 4 shown. This promotion is labeled with the brand ➂. However, the messaging system MSYS of the television set DTV will start a waiting process in the background, which checks whether the confirmation message from the video recorder DVR arrives within the 30s timeout. This waiting process running in the background is in 7 referred to as WPROC. If the confirmation message is still received within the 30s waiting time, the waiting process WPROC would end the waiting process without starting any further action. However, if the confirmation message does not arrive within this time, the waiting process GPROC ends the waiting period by sending a deletion message to the CMM of the television set DTV, with which the video recorder DVR is to be deleted from the list of active HAVi devices. This process is in 7 marked with the mark ➃. In addition, the CMM will then also inform the user interface UI that the video recorder has been removed from the list of active HAVI devices, see mark ➄. This can be implemented by the user interface so that a changed display for the network structure appears on the display of the television set DTV. For example, the new network structure 5 being represented.

8th shows the same use case as 7 however, monitoring the receipt of the confirmation message according to a second embodiment of the invention. Under the ➀ brand, the MSYS messaging system is informed again that the play command should be triggered on the DVR video recorder.

The transmission is under brand ➁ the associated HAVi message the video recorder DVR shown. Because the video recorder DVR is inactive is the confirmation message not retransmitted within the set 2s timeout period. The MSYS messaging system then notifies the unter brand User interface UI about that a disturbance is present in the DVR video recorder.

In addition, the user interface is released for further processing. Next, the MSYS messaging system generates an activity check message and sends it to the DVR with the problematic behavior, brand ➃. In particular, the standardized HAVi message Message :: PING is sent to the DVR video recorder as an activity check message. This transfer takes place with the maximum timeout of 30 seconds defined in HAVi. If this activity verification message is not confirmed by the DVR video recorder within the 30s, the MSYS messaging system of the DTV television ensures that the entry in the list of active HAVi devices in the CMM for the DVR video recorder is deleted. This is in 8th marked with the mark ➄. Finally, the CMM in turn notifies the user interface that the video recorder DVR has been deleted from the list of active HAVi devices in the CMM, for example with the CMM Event GoneDevices. The user interface can implement this notification again as to 7 explained.

Various modifications and modifications of the described exemplary embodiments are possible and are still regarded as belonging to the invention. For example, data transmission in the home network does not necessarily have to be based on the bus protocol of the IEEE 1394 bus. Instead, wireless networking of the home network devices can also be considered. Here, for example, the wireless transmission method HIPERLAN / 2 or IEEE 802.11b, etc. is available. Other wired transmission methods such as Ethernet, Powerline data bus, ring bus systems, etc. can also be used instead. In the exemplary embodiments shown, the messaging system of the HAVi-FAV device, namely the digital television set, was modified. It would also be possible to modify the messaging system of another device. A digital set-top box or the digital satellite receiver DSAT is mentioned as an example. A device with an existing display does not necessarily have the extended messaging system ben. It is also sufficient that the device can be connected to a display device with the extended messaging system.

Claims (11)

Process for processing via a transmission medium to be transferred Messages in a network of distributed stations, in which a message a maximum duration in terms of is assigned to the reply transfer, characterized by the following steps: after dispatch the message monitoring, whether the reply arrives within a first certain time, releasing the initiating the message transmission Component (UI) if the reply does not arrive within the first certain time, surveillance in the background whether the reply arrives within a second specified time, discharge of the Station to which the message was addressed from a list of active network stations if the reply within the second does not arrive for a certain time. Process for processing data to be transmitted via a transmission medium Messages in a network of distributed stations where a message a maximum duration in terms of the reply transfer is assigned, characterized by the following steps: to Sending the message monitoring, whether the reply arrives within a first certain time, releasing the the messaging initiating component (UI) if the response is within the first does not arrive after a certain time, sending an activity verification message Monitoring to the network station to which the original message was also sent whether the reply to the activity review message arrives within a second specified time, discharge of the Station to which the message was addressed from a list of active network stations if the reply within the second does not arrive for a certain time. The method of claim 1 or 2, wherein the releasing of the message transmission initiating component (UI) is accompanied by the generation an error message for the unresponsive network station. Method according to one of the preceding claims, wherein the second specified time of the maximum duration for the Reply transmission equivalent. The method of claim 4, wherein the maximum duration for the retransfer Is 30 seconds. Method according to one of the preceding claims, wherein the message transmission is based on the HAVi standard whereby HAVi for home audio / video interoperability stands. Network station for a network of distributed stations, with means for the exchange of Messages with another station, being a message transmission a maximum duration in terms of the reply transfer assigned, characterized by monitoring means (MSYS) for monitoring, whether the reply arrives within a first certain time, release means (MSYS) to release the component that initiates the message transmission, if the reply does not arrive within the first specified time, second monitoring means (WPROC) for monitoring in the background whether the reply arrives within a second specific time, administrative funds (MSYS), which the station to which the message was addressed was from a List the active network stations if the reply is within the second specified time does not arrive. Network station for a network of distributed stations, with means for the exchange of Messages with another station, being a message transmission a maximum duration in terms of the reply transfer assigned, characterized by monitoring means (MSYS) for monitoring, whether the reply arrives within a first certain time, release means to release the component that initiates the message transmission (UI) if the reply does not arrive within the first specified time, means to Generate an activity verification message (PING) which is an activity verification message to the network station to which the original message was also sent generate following the finding that the reply to the first message transmission has not arrived within the first certain time, second monitoring means (PING) for monitoring, whether the reply to the activity review message arrives within a second specific time, administrative funds (PING) the station to which the first message was addressed from a list of active network stations if the reply on the activity review message does not arrive within the second specified time. Network station according to claim. 7 or 8, with means which is an error message for generate the unresponsive network station accompanying the release of the message transmission initiating component (UI). A network station according to any one of claims 7 to 9, wherein the maximum duration for the reply transmission to the activity check message is set to 30 seconds. Network station according to one of claims 7 to 10, the network station for data exchange with other network stations according to the HAVi standard is designed, with HAVi for Home audio / video interoperability is here.