MXPA00012213A - Domestic system resource access priority management method and device for the implementation thereof - Google Patents

Abstract

The invention relates to a method for managing access priorities for applications with respect to the resources of devices that are connected by means of a communication network. The inventive method is characterised in that it comprises the following steps:each application is attributed an access priority with respect to the resources of the network, whereby said levels include at least the following levels (a) a first access priority for an application that does come under the direct control of the user, (b) a second access priority level for an application that can be directly controlled by the user, and an authorisation for a first application to preempt access to a resource previously obtained by a second application according to the respective access priorities of the first and second applications.

Description

PROCESS TO ADMINISTER PRIORITIES OF ACCESS TO RESOURCES IN A DOMESTIC NETWORK AND DEVICE FOR IMPLEMENT THE SAME The invention relates to the management of access priorities by applications to resources in a communication network, domestic, as well as to a device for implementing the process. In a home network, several devices are linked by a communication network and communicate by means of a common language. These networks are evolving towards the transmission of audio and video data, and for example they can be based on a common serial bar of the IEEE 1394 type. The devices connected to the network can have "resources", which is to say particular facilities. A television has for example a tuner, a cathode ray screen, while a video recorder has a tuner and a recording facility. Since the resources of a device can be made available to other devices on the network (for example, a video recorder records a transmission by controlling the television tuner), conflicts of access to resources may arise, a resource that may receive contradictory orders from various applications. The purpose of the present invention is to propose the administration of access priorities. The object of the invention is a process for managing priorities of access of applications to resources of devices linked by a communication network, characterized in that the process comprises the steps of: - assigning, to each application, a priority level of access to the resources of the network, the levels comprising at least the following levels: (a) a first level of priority access for an application that is not under the direct control of a user, (b) a second level of access priority for an application that can be ordered directly by a user, authorizing pre-occupation for a first application of access to a resource, access that was previously obtained by a second application, as a function of the respective access priorities of the first and second applications. According to a variant modality, a resource allows simultaneously accesses by at least N applications, N that is greater than or equal to 1. According to a variant modality, the pre-vacance step is preceded by a negotiation phase during which The first application transmits a message to the second application asking if it agrees or refuses to abandon access in favor of the first application. According to a first example embodiment, a pre-vacancy phase of an application having the second priority level by an application having the first priority level is always preceded by a negotiation phase. According to a first example mode, a pre-vacancy phase of an application having the second priority level by an application having the second priority level is always preceded by a negotiation phase. Specifically, according to a first example mode, the second level of priority is the level marked by the applications controllable by the user. Since its presence is assumed, a negotiation is carried out in the previous case, before any pre-occupation. According to a second modality, at least three levels of priority are provided, the third level of priority that is greater than the second level of priority, the latter being greater than the first level of priority, there is a negotiation phase if the The priority level of the first application is identical to or lower than the priority level of the second application. According to a second method, there is a pre-vacancy directly without negotiation if the security level of the first application is greater than the security level of the second application. According to a variant of the modalities, an application that makes an attempt to reserve access to a resource already reserved by the N client applications is placed in a queue, waiting for the unlinking of the resource by one of the N client applications. According to a variant of the modalities, a waiting application is placed in a queue only if it is specified by this application in its access request. The inventive process may additionally include the steps of: assigning a primary level of access rights, for a given resource, to an application that obtains access requested to this resource first, allocating a second level of access rights to other applications that they reserve the resource, the access rights of the second level that are such that they do not interfere with the access rights of the primary level. According to a variant modality, after an order transmitted by an application that has a secondary level access right to a resource, the resource itself determines whether this order interferes with the access rights of the primary level or not. According to a variant modality, a resource is in accordance with any order received from the application that has a primary level access right to this resource, even if the execution of the order interferes with previously received orders from an application that has a secondary level of access right. According to a variant modality, pre-occupation and / or negotiation is authorized, only to force the abandonment of an access retained by an application that has a primary access level. It should be noted that the above characteristics that correspond to the concepts of primary and secondary access level, as well as additional features that relate to these concepts described in the following, must subsequently be able to form the subject of an independent set of claims. Other features and advantages of the invention will become apparent through the description of an exemplary, non-limiting mode illustrated by the accompanying figures in which: Figure 1 is a block diagram of a device network that implements the process according to the invention, Figure 2 is a diagram representing the logical organization of a device of Figure 1.

In the various figures, the same elements have identical references.

The network of Figure 1 consists of the present example embodiment of a common bar in series that complies with the IEEE 1394-1995 standard. This common bar, referred to 1, links devices 2, 4, 5 and 6. The term "device" is understood to mean a physically separate device linked to the network. Each device may include one or more sub-devices, such as the sub-device 3. These sub-devices may be resources, which are device installations. The resources form modules of computer programs (or "elements of the program") within the meaning of the document "HAVi" mentioned later. By way of example (see Figure 2), one device A is a digital television decoder, while another device, device B, is a video recorder. The decoder A has two resources, specifically a tuner 12 and a demultor iplexor 13. The video recorder B also has two resources: a tuner 14 and a recording facility 15. Each of the devices A and B includes an application (18). and 19, respectively) which is a graphical user interface, which allows a user to directly administer the facilities of each device. The user interface of the device A makes possible in accordance with the present example mode the administration of the recording, by another device of the network, of the programs emanating from the demultor iplexor 13. A resource may be resident, ie present from the beginning it is a device, but it can also be downloaded. For the implementation of the facilities and protocols related to HAVi, each device has appropriate means of processing information, memory and connection. The processing means may comprise a microprocessor 7 or a microcontroller or the like associated with several specialized circuits for more specific tasks (error correction, signal processing, demodulation, etc.). The memory medium (10) can be reprogrammable or static memories, fixed to contain the core of the computation program and / or downloaded segments of the code and / or data. The memory medium may also include removable storage devices such as microprocessor cards and PCMCIA-type cards, as well as hard drives or other storage media. The connection means includes inter alia the interface to the IEEE 1394 common bar, referenced 9 in Figure 1. It is quite obvious that the invention is not limited to a particular structural implementation. According to the present description, the various elements of a device are linked by virtue of an internal common bar 8. Completely obvious, the sub-devices also communicate with the internal common bar, but they have been illustrated separately, since these sub-proposals can be applications of computer programs executed by the microprocessor 7, as well as segments of physical equipment separated from the microprocessor. Each device also includes a register (referred to 16, 17 respectively for each of devices A and B). The registration forms the subject of a French patent application in the name of the applicant, filed on April 23, 1998 and having the number 9805110. Another patent application that relates to the subject matter of the present patent application is the application of French Patent 9807187, filed on the priority date of the present application. This other patent application relates to the programming of resource actions in a communication network. Other aspects that relate to the present invention are further described in the article "The HAVi Architecture - Specification of the Home Audio / Video ineroperabi 1 ity (HAVi) Architecture" dated May 11, 1998 in version 0.8 thereof and made publicly available from 15 of Greater 1998. Now a version 1.0 of this document is available. These documents are also referred to for additional particularities with respect to the various elements of the network, the present description which is limited to the elements required to explain the invention. The registration of a device (also referred to as the "local registry" for this device, as opposed to "remote registries" that reside on other devices) participates in the administration of all the resources of this device. For this purpose, the registry includes a table in which the other device resources will be registered when indicating their attributes (type of resource, resource identifier in the network, etc.). When a computer program module has to communicate with another module of the local computer program, you can obtain the list of these modules through the local registry, which has a known local address. When a computer program module has to communicate with another remote computing program module of another device, it can obtain the address ("SEID") of the remote computer program module by going through the local registry. A computer program module can determine a list of modules that correspond to certain search criteria, regardless of the location of these modules, by transmitting a request to the local registry that propagates this request to the remote registers. The request includes in the form of parameters the criteria for selecting the computation modules after the 'search, for example to the type of module (display, recorder, etc.). In this regard, the resources of a device are also recorded at the local registry level, as are the other computer program modules. A downloaded module is registered with the device registry that works as the execution program for this module.

The register is a module that is a program according to the present exemplary embodiment, stored in the memory 10 and implemented by the microprocessor 7 of a device. An application can be one of the following two profiles: User or Machine. The user profile corresponds to an application that is able to interact directly with the user, such as for example the graphic interface 18 of the user of device A. The machine profile corresponds to an application that is not directly controlled by a user, but that implements for example, a programmed action. An application can control a resource. An application can also be a resource and in this respect it is controlled by another application. According to another example mode, a User profile application will have precedence over a Machine profile application when it relates to the resolution of a resource reservation conflict. The User profile will be said to have a higher priority level than the Machine profile. A resource has a number of properties: A resource can be of a class called static or dynamic. A dynamic resource can be divided into several independent segments, by specifying appropriate parameters. Typically, the bandwidth is a dynamic resource: an application that reserves a bandwidth will have to specify the bandwidth that is reserved. A resource of the static class is a resource that can not be reserved in this way. A dynamic resource will have a reservation status corresponding to the remaining amount available. A static resource can be one of three reserve states, a so-called available state, a so-called shared state, and a so-called secured state. In the available state, the resource is not controlled by any application. In the shared state, the resource is controlled by at least one application, but other applications can still use the resource, with certain restrictions that refer to the control orders allowed by these other applications. In the insured state, the resource is controlled by at least one application and will reject any control order that originates in another application. In addition, with each resource there will be associated a descriptor, that is to say a structure or data record, which includes values of variables that identify the facilities of the resource, as well as an address in the network. As already mentioned, this descriptor is registered at the local registry level. According to the present example embodiment, the resource descriptor indicates the activity domain of the resource (for example audio / video, heating, home devices, etc.), the type of resource that indicates its function (tuner, modem decoder, etc. the level of accessibility ("local" resource, accessible only by applications that reside in the same device, or "public" resource, also accessible by applications executed on different platforms of the device in which the public application resides). of resources is based on a reservation mechanism, a reservation necessary for the implementation of control orders and more generally for any write access that changes the state of a resource, a reservation in general is not necessary for access Once you have agreed with a reservation, the application becomes a client application of the resource: it has control of the resource, but it does not It is necessarily the only application for which this is the case, hence the need for a mechanism to resolve conflicts of access to the resource. Each device is terminated with a computer program module referred to as the "resource manager". In the network of Figure 2, the resource managers of devices A and B refer to 20 and 11, respectively. These modules collaborate with the registers. The registers maintain a list of the computer program modules locally (resources, applications, etc.) available and the resource manager manages reservations for local resources. The information maintained by the registers is relatively static, while that maintained by the resources in general is prone to evolve rapidly. In accordance with the present exemplary embodiment, a resource manager obtains the list of local, respectively remote, resources directly from the local registry, respectively from the local registry after the latter has dispatched a request for information to the remote registers. Resources not resident in this way are easily accessible to the resource manager. For example, when a function control module ("FCM" according to the HAVi terminology) is downloaded from a base audio / video device ("BAV" according to the HAVi terminology), this control module is registered with the local registry of the device that serves as its execution program, such as an audio / video device with full facilities ("FAV"). The principles used for the reservation are as follows: before dispatching a resource control order, an application must reserve this resource with the resource analyzer of the device in which the resource resides, and an application must release a resource that does not I'm using it for longer. According to the present example embodiment, an application that wishes to make a reservation determines the address of the resource manager of the device in which the resource resides by means of the registration of the device in which the application resides. Once the address has been obtained, the application can contact the resource manager with a view to find out the status of the resource. On the other hand, once the reservation has been obtained, the application making this reservation obtains control of the resource and directs its control orders directly to the resource. The resource manager does not contact each other subsequently to indicate whether the resource needs to be released. Each resource maintains a data structure known as the "containment structure", which contains the following information: (1) Static information. This type of information does not have a previous tendency to evolve. This information can be requested by the resource manager from the resources. (a) The resource control mode. The control mode can be one of the following: transparent, sharable, exclusive. (b) Maximum number of supported applications. This field is used for the case of the sharable or exclusive mode. The resource indicates the maximum number of applications supported simultaneously, the minimum being 1. (2) Dynamic information (a) Information that is related to the applications that control the resource. Among the stored data that relate to each application are: the profile of the application (User or Machine), - as appropriate, when dealing with a primary or secondary application (see below), called private data reserved for a user yet not defined, - a text field that includes a description of the reason for the reservation (for example, registration of the Z-channel). (b) Current status of the resource: Available, Shared, Insured. (c) Number of applications that control the resource (d) List of applications that control the resource. (e) List of applications that are waiting to be able to control the resource (for example, because the maximum number of these applications for this resource has been exceeded) The applications, like the resources, are identified by a defined address of the HAVi document and have the name "SEID." More specifically, the resource maintains a minimum of data regarding to the applications that it controls, with a view to implement the pre-occupation and negotiation mechanisms. For the implementation of the mechanism to divide into primary application and secondary applications, a resource stores at least the identifier of the primary application. In this regard, reference is made to Table 1 in particular. In the case of the sharable control module, the type of authorized access will also be indicated: division of applications in the primary application and in secondary applications, or equality of processing for all applications. In the Transparent control mode, the resource is in agreement with a simultaneous control without restriction in the part of the various applications, without making any distinction between the applications. In Shareable mode, the various applications can control the resource at the same time, but this resource will implement access resolution and resource sharing processes, there must be a risk that application commands will lead to incorrect operation. An example is that of a decoder A of Figure 2. The tuner of this device is adjusted for the reception of a signal originating from a particular transponder, corresponding to a certain multiplexed current. Within this stream the iplexor demult has the ability to mark the packets corresponding to one service or another, and to extract these packets to the client applications. Assuming that a given stream carries some ten services, separate applications can use the demultiplex resource to access identical or different services. The demultiplexer then operates as a server. A conflict arises when an application wants to change the transponder. This implies that any other application will lose access to the services transmitted in the current transponder. According to the invention, the preferred process for resolving a conflict is as follows: client applications of a resource are classified into secondary primary client applications. An individual application can be a primary application for a resource: initially it is one that reserves the resource first. All other applications are applications is secondary. The resource accepts all the orders that originate from the primary application, but can accept only certain orders, in a limited way, from the secondary applications. The commands of the secondary applications are taken into account, only if they are not in conflict with the orders of the primary application. In the example of the iplexor demulture given above, only the primary application has the possibility of changing to the transponder. Secondary applications have only the right to choose a service in the current transponder. According to a variant modality, the primary application informs its final user (for example, the television viewer) of the disturbances that its action may cause. Returning to the previously described example, before allowing a user to change the transponder, the primary application requests as appropriate from the resource handling the tuner in question the list of secondary applications, as well as the list of the corresponding reservation reasons. These reasons are displayed for the attention of the user, who may or may not make the decision to continue with the change of the transponder, with the knowledge of the possible repercussions of the action. According to the present exemplary embodiment, all secondary applications have identical order possibilities. Two processes can be distinguished: according to the first process, an application can not disturb or disrupt the commands previously transmitted to the resource by another application ("principle of mutual respect"), while according to the second process, an application can upset another application. In all cases, what constitutes a "disturbance" of a secondary application by another depends on the nature of the controlled resource and it is the latter that will have to be fixed. According to the present example modality, is the principle of mutual respect that is implemented with respect to access conflicts between secondary applications. According to a variant modality, as already mentioned in conjunction with the primary application, a secondary application advises, if necessary, the end user of the same of the restrictions imposed on the action of the same. As an example, for a shareable resource, Table 1 gives some of the information stored at the level of each resource: TABLE 1 In exclusive mode, the resource can only be controlled by an individual application at any given time. The resource stores at least the identity of this application, as well as its priority level (User or Machine type according to the present example mode). As an example, one can take control of the mechanisms of a video recorder, such as device B of Figure 2. A conflict may arise if one application requests the recording of a transmission, while another application slightly later asks for the execution of the recording medium. In this case, the first application will have exclusive control. Depending on the type of resource, the access mode to a resource may differ from several orders. For example, commands that change the operation mode of a resource can generate conflicts and therefore justify an exclusive or sharable control mode, while all other commands, for example read access or event requests, are managed according to transparent mode. To reserve a resource, an application transmits a corresponding order to the local resource manager to the resource or to the local administrator to the application itself. This order includes as parameters the information related to the application described subsequently in the containment structure at the resource level. No reservation is made by an application with respect to a resource in transparent mode. In accordance with the present example, a reservation is made with respect to the immediate obtaining of control of a resource, ie the concept of time is not taken into account for the purpose of simplifying the present description. However, the principle is similar for access conflicts of one and the same resource with respect to future periods that overlap. The patent application having the same priority date, as the present application, refers in particular to these reservations with respect to future periods. According to a current state of the resource, three cases can be presented: - The reservation is accepted and the application becomes the primary application or a secondary application. This is the case when the resource is initially in the available or shareable state, respectively. - The reservation is rejected as the resource is insured (for example, because the maximum number of applications has been reached.) Application can request, in the form of an indicator in the reservation order, that it be placed in the queue for This resource, and that the notification of the resource manager is obtained when the latter has automatically assigned a new access level (whether a secondary access becomes a primary access, or an application in the queue becomes a secondary application). or primary.) The address of the application is then stored in a stack of the containment structure for the appropriate resource - The placement of the application on hold if its profile is such that it allows to negotiate the title of the primary application with the application The current negotiation or pre-vacancy mechanism is implemented, according to the present example, by means of the resource manager. resources transmits the result of the reservation back to the application. If the reservation is accepted, the message also includes the information as to whether the application is primary or secondary.

When the application has gained control of the resource and its action has ended, it transmits a resource release order to the resource manager. The latter then deletes the application and the information that applies to it from the appropriate content structure. This is also the case for an application that waits for which it no longer needs a resource with respect to which it has tried to make a reservation in the past, it must release the resource. According to the present example modality, two mechanisms are provided to replace a primary application with another application: pre-employment and negotiation. The type of mechanism is identified in the reservation order sent by an application to the resource manager. The pre-vacancy phase can be presided over by a negotiation phase. When an application wishes to negotiate the status of the primary application with the primary application, it sends a message in this regard to the resource manager, who in turn transmits a message to the primary application. The latter can either agree or reject to give its place. An application of the user type may transmit, for example, repetition to the user himself. An application can also implement the pre-vacancy mechanism to be appropriate for the state of the primary application. In this case, the resource manager verifies that this application actually has priority to make this request, in relation to the priority of the primary, current application. The pre-vacancy is authorized, the resource manager sends a transfer order that the primary application is obliged to accept. A given time is then agreed to the primary application to release the resource. If we comply with this time, the resource manager makes the transfer of the work of the resource. In conjunction with the mechanism for splitting client applications into primary application and secondary applications, the resolution of conflicts with respect to the position of the primary application during the reservation adheres to the following rules, given the point of view of the case where only There are User and Machine profiles: (1) An application with a User profile always has the priority with respect to an application with a Machine profile. (2) The first application that reserves a shareable resource becomes the primary application. A primary application can interfere with the commands of secondary applications. A secondary application can not interfere with a primary application command. (3) An application with a user profile, nunc, is submitted to the pre-vacancy right of another application (User or Machine) without any negotiation phase. (4) When a primary application releases a resource, it is the secondary application that has the highest priority level that the primary application becomes. In the case where several secondary applications have this priority level, it is the most previous application that becomes the primary application. A waiting primary application can then take the place of the secondary application. There can be four cases of conflict, depending on the profile of the primary application and that of the application that seeks to be a reservation (it will be assumed that there is a negotiation, wherever the primary application has the User profile): (a) The primary application has a User profile and the application that requests the reservation has a Machine profile: In this case, the resource transmits a message to the User application to verify if the latter can yield. This is the negotiation. If this is the case, the machine profile application becomes the primary application. Otherwise, the machine application abandons its intent. An example that corresponds to this case is that of a television viewer who sees a service broadcast on a transponder A, while a pre-programmed video recorder will record a service on a transponder B, using the same tuner . (b) The primary application has a Machine profile and the application requesting the reservation has a profile User: Before replacing the primary application Machine with the User application, the resource manager informs the User application of the potential consequences of his replacement and asks him to confirm the replacement, while giving him the possibility of leaving the primary application to complete his task. An example corresponding to this case is that where a video recorder is recording a service of a transponder A, while a television viewer wishes to observe a service on a transponder B, using the same tuner. The television viewer is then informed that the recording in progress will have to be stopped if he confirms his decision. (c) The primary application has a User profile and the application requesting the reservation also has a User profile: In this case, the primary application will decide to maintain or abandon its primary level: the principle is the same as in the case (a) : there is negotiation An example that corresponds to this case is that where a first television viewer is observing a service in a first transponder (which is controlled by a primary application), while a second television viewer wants to observe another service in another transponder, using the same tuner. The second television viewer will only be able to adjust the tuner to the frequency of the new transponder with the agreement of the first television viewer. (d) The primary application has a profile Machine and the application that requests the reservation also has a machine profile: Since, according to the present example, all the applications with machine profile have the same priority, the primary application finishes its task without being replaced. According to a variant modality, other application profiles are provided for: Second plane, Installation, Security and System, corresponding respectively to low priority applications occupied with background tasks (for example, cleaning obsolete data), used applications during the installation and configuration of the network, applications that inform the user of certain important events (security alarms, as an example), and system applications (for example, records and resource managers). With more than two existing profiles, the behavior of the system is generally described in Table 2. The variant modality, mentioned above, comprising more than two profiles, the Security and System profiles have as an example higher priority levels than the user profile. There is never the pre-vacancy of an application with a User profile by an application of identical or lower priority level without negotiation phase. However, according to the example described in Table 2, there is no negotiation i when the primary application has a User profile, but the application that seeks control has a priority level strictly at t o.

TABLE 2

Claims (13)

1. Process for administering access priorities in applications to device resources linked by a communications network, characterized in that the process comprises the steps of: assigning, to each application, a priority level of access to the resources of the network, the levels comprising at least the following levels: (a) a first level of access priority for an application that is not under the direct control of a user, (b) a second level of access priority for an application that can be order directly by a user, authorize pre-occupation for a first application of access to a resource, with the access previously obtained by a second application, as a function of the respective access priorities of the first and second applications.

2. The process according to claim 1, characterized in that a resource simultaneously allows accesses to at least M applications, N which is equal to or less than 1.

3. The process according to any of claims 1 or 2, characterized in that the Pre-vacancy step is preceded by a negotiation phase during which the first application transmits a message to the second application that asks if it agrees or declines to abandon access in favor of the first application.

4. The process according to the rei indication 3, characterized in that a pre-vacant phase and an application having the second priority level by an application having the first priority level is always preceded by a negotiation phase.

5. The process according to rei indication 3 or 4, characterized in that a pre-vacancy phase of an application having the second priority level by an application having the second priority level is always preceded by a negotiation phase. The process according to claim 3, characterized in that at least three priority levels are provided, the third priority level being higher than the second priority level, the latter being greater than the first priority level, there is a Negotiation phase if the priority level of the first application is identical or lower than the priority level of the second application. The process according to one of claims 3 to 6, characterized in that there is a pre-occupation directly without negotiation, if the security level of the first application is greater than the security level of the second application. The process according to one of claims 2 to 7, characterized in that an application making an attempt to reserve access for a resource already reserved by the N client applications is placed in a queue, waiting for the release of the resource by a of the N client applications. 9. The process according to claim 8, characterized in that the application is placed on hold in a queue only if it is specified by this application in its access request. The process according to one of the preceding claims, characterized in that it additionally includes the steps of: - assigning a primary level of access rights, for a given resource, to an application that has access requested to this resource first, assign a level of secondary rights of access to other applications that reserve the resource, the access rights of the secondary level that are such that they do not interfere with the access rights of the primary level. The process according to claim 10, characterized in that, after an order transmitted by an application having a secondary level access right to a resource, the resource itself determines whether this order interferes with the access rights or not. of the primary level. The process according to any of claims 10 to 11, characterized in that a resource is in accordance with any order received from the application that has a primary level access right to this resource, even if the execution of the order interferes with orders received previously from an application that has a secondary level of access rights. The process according to one of claims 10 to 12, characterized in that the pre-vacancy and as an appropriate negotiation, is authorized only to force the abandonment of an access retained by an application having a primary access level.