GB2504725A

GB2504725A - Resource sharing between devices

Info

Publication number: GB2504725A
Application number: GB1214144.6A
Authority: GB
Inventors: Nigel Cardozo; Rohit Ail; Woosung Choi; Kupesan Kulendiran; Ziran Sun
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2012-08-08
Filing date: 2012-08-08
Publication date: 2014-02-12
Anticipated expiration: 2032-08-08
Also published as: KR102072003B1; KR20140020193A; GB201214144D0; GB2504725B

Abstract

Devices and methods for communicating over a network, with one or more other devices within a group of devices are disclosed. Each device can transmit and/or receive resource information over the network, the resource information including a resource identifier for identifying a remote resource accessible through another device and source information for identifying a location from which the remote resource can be obtained. A device can select one of a plurality of resources including the remote resource, and in response to the remote resource being selected, is arranged to request the selected remote resource from the location identified by the source information in order to share the remote resource.

Description

Resource Sharing Between Devices

Field of the Invention

The present invention relates to resource sharing between devices. In particular, the present invention relates to transmitting and receiving resource information for identi'ing a resource accessible through a device over a network.

Background of the Invention

In recent years, technological advances have resulted in an increasing number of devices becoming commercially available that include networking capabilities.

Originally restricted to desktop computers, it is now common for devices such as televisions and mobile telephones (smartphones'), and even household appliances such as fridges, to include network interfaces. Typically, a central server or hub is required to manage devices in a home network, which is configured to maintain a permanent i network in which the same security settings are applied to communications between all devices on the network. As network connections become more common in mobile devices such as tablet computers, personal digital assistants (PDAs), laptop computers and smartphones, there is a need for a flexible approach to network management that can respond to different devices frequently joining and leaving the network, and allow efficient resource sharing between such devices. At present, the only way to add new functionality to a device is to upgrade to a newer version that includes the desired functionality, for example upgrading a non-GPS (Global Positioning System) digital camera to a GPS-enabled camera to allow geo-tagging of photos.

The invention is made in this context.

Summary of the Invention

According to the present invention there is provided a device for communicating over a network with one or more other devices wthin a group of devices, the device comprising a resource information collecting module arranged to receive resource information from one of the other devices, the resource information including a resource identifier for identifying a remote resource accessible through the other device and source information for identifying a location from which the remote resource can be obtained, and a selection module for selecting one of a plurality of resources including the remote resource, wherein in response to the remote resource being selected, the device is arranged to request the selected remote resource from the location identified by the source information.

Prior to receiving the resource information the device can be arranged to determine whether the group of devices exists and to request the resource information from the one or more other devices if the group of devices exists, or set up the group of devices if it does not exist, and can be arranged to set up the group of devices by broadcasting a group setup message over the network to invite the other devices to join the group.

io After broadcasting the group setup message the device can be arranged to respond to a request from one of the other devices to join the group by authenticating said one of the other devices, and transmitting an authorisation token to said one of the other devices in response to a successful authentication result, the authorisation token comprising a token for use in authenticating communications between devices in the same group.

The device can be arranged to determine whether the group of devices exists by broadcasting a group search message including a predetermined group identifier for identifring the group, waiting a predetermined time, and determining that the group does not exist if a response indicating the existence of the group is not received from the network within the predetermined time.

The device can be further arranged to obtain location information about a current location of the device, and to determine whether the group of devices exists in response to the location information indicating that the device is at a predetermined location.

Prior to receiving the resource information the device can be arranged to broadcast a resource information request including a predetermined group identifier for identil5ting the group of devices, to request resource information from any devices on the network that arc included in the group.

When resource information for a plurality of resources is received the device can be arranged to determine based on the received resource identifiers whether one of the resources can be obtained from a phirabty of different locations, and in response to the selection module selecting said one of the resources, the device can be arranged to select a preferred one of the plurality of different locations from which to request the resource based on predetermined criteria.

The selection module can be arranged to rank the plurality of resources according to one or more predetermined ranking criteria, before selecting one of the resources.

The selection module can be arranged to rank the plurality of resources based on, for each one of the plurality of resources, information about: a time since the resource was last accessed; and/or a current state of the resource; and/or an attribute score of the resource; and/or a usage history of the resource.

io The resource information can inchide type information for identifying a type of the remote resource, and in response to the selection module selecting one of the resources, the device can be arranged to determine based on the resource information whether an alternative resource of the same type as the selected resource and having a higher ranking than the selected resource is available.

The device can be further arranged to transmit local resource information to the one or more other devices in the group over the network, the local resource information comprising information about a resource accessible through the device.

The device can be arranged to store the received resource information for a predetermined time period and request updated resource information from the other device after the predetermined time period has expired, and in response to updated resource information not being received, the device can be arranged to delete the stored resource information for the other device.

The selection module can be arranged to select one of the plurality of resources in response to user input, by providing a user with information about the plurality of resources and receiving a user command selecting one of the plurality of resources.

According to the present invention, there is also provided a device for communicating over a network with one or more other devices within a group of devices, the device comprising a resource information providing module arranged to generate resource information inchiding a resource identifier for identi1ring a resource accessible through the device and source information for identifying a location from which the remote resource can be obtained, and to transmit the resource information to the one or more other devices over the network, wherein in response to a request to use the resource received from one of the other devices, the device is arranged to provide the requested resource to said one of the other devices.

The device can be arranged to communicate over a first network according to a first network protocol and to communicate over a second network according to a second network protocol, wherein the group of devices may include a first other device on the first network and a second other device on the second network, and wherein in response to a request for resource information from the first other device, the resource information providing module can be arranged to transmit resource information about a remote resource provided by the second other device and accessible through the device.

In response to a request from the first other device to access the remote resource, the device can be arranged to request the remote resource from the second other device to provide the remote resource to the first other device.

The request received from said one of the other devices may indude a group identifier for identifying the group of devices, and the device can be arranged to determine whether authentication is required in the identified group, and in response to a determination that authentication is required, can be arranged to authenticate said one of the other devices before providing the requested resource.

According to the present invention there is further provided a method for use in a device for communicating over a network with one or more other devices within a group of devices, the method comprising receiving resource information from one of the other devices, the resource information including a resource identifier for identifying a remote resource accessible through the other device and source information for identifying a location from which the remote resource can be obtained, selecting one of a plurality of resources including the remote resource, and requesting the sdected remote resource from the location identified by the source information, in response to the remote resource being selected.

The method can further comprise prior to receiving the resource information, determining whether the group of devices exist, requesting the resource information from the one or more other devices if the group of devices exists, and setting up the group of devices if it does not exist, by broadcasting a group setup message over the network to invite the other devices to join the group.

The method can further comprise after broadcasting the group setup message, responding to a request from one of the other devices to join the group by authenticating said one of the other devices, and transmitting an authorisation token to said one of the other devices in response to a successful authentication result, the authorisation token comprising a token for use in authenticating communications between devices in the same group. I0

Determining whether the group of devices exists can comprise broadcasting a group search message including a predetermined group identifier for identiing the group, waiting a predetermined time, and determining that the group does not exist if a response indicating the existence of the group is not received from the network within is the predetermined time.

The method can further comprise obtaining ocation information about a current location of the device, wherein it is determined whether the group of devices exists in response to the location information indicating that the device is at a predetermined location.

The method can further comprise prior to receiving the resource information, broadcasting a resource information request including a predetermined group identifier for identiIring the group of devices, to request resource information from any devices on the network that are included in the group.

When resource information for a plurality of resources is received, the method can further comprise determining based on the received resource identifiers whether one of the resources can be obtained from a plurality of different locations, and selecting a preferred one of the pitiraBty of different ocations from which to request the resource based on predetermined criteria, in response to said one of the resources being s&ected.

The method can further comprise ranking the plurality of resources according to one or more predetermined ranking criteria, before selecting one of the resources.

The plurality of resources can be ranked based on, for each one of the plurality of resources, information about: a time since the resource was last accessed; and/or a current state of the resource; and/or an attribute score of the resource; and/or a usage history of the resource.

The resource information can include type information for identifying a type of the remote resource, and the method can further comprise determining based on the resource information whether an alternative resource of the same type as the selected resource and having a higher ranking than the selected resource is available, in Jo response to said resource being selected.

The method can further comprise transmitting local resource information to the one or more other devices in the group over the network, the local resource information comprising information about a resource accessible through the device.

The method can further comprise storing the received resource information for a predetermined time period, requesting updated resource information from the other device after the predetermined time period has expired, and deleting the stored resource information for the other device, in response to updated resource information not being received.

Selecting one of the plurality of resources can comprise providing a user with information about the plurality of resources, and receiving a user command selecting one of the plurality of resources.

According to the present invention, there is further provided a method for use in a device for communicating over a network with one or more other devices within a group of devices, the method comprising generating resource information including a resource identifier for identifying a resource accessible through the device and source information for identifying a ocation from which the remote resource can be obtained, transmitting the resource information to the one or more other devices over the network, receiving a request to use the resource from one of the other devices, and providing the requested resource to said one of the other devices.

The device can be arranged to communicate over a first network according to a first network protocol and to communicate over a second network according to a second network protocol, wherein the group of devices may include a first other device on the first network and a second other device on the second network, and wherein in response to a request for resource information from the first other device, resource information about a remote resource provided by the second other device and accessible through the device can be transmitted to the first other device.

The method may further comprise requesting the remote resource from the second other device to provide the remote resource to the first other device, in response to a request from the first other device to access the remote resource. I0

The request received from said one of the other devices may indude a group identifier for identifying the group of devices, and the method may further comprise determining whether authentication is required in the identified group, and authenticating said one of the other devices before providing the requested resource, in response to a determination that authentication is required.

A computer-readahk storage medium may be arranged to store a computer program which, when executed, performs the method.

Brief Description of the Drawings

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 illustrates a group of devices arranged to communicate over a network, according to an embodiment of the present invention; Figure 2 illustrates a format for transmitting resource information from one device to another, according to an embodiment of the present invention; Figure 3 illustrates a format for storing received resource information, according to an embodiment of the present invention; Figure 4 illustrates a device for receiving resource information about a shareable resource, according to an embodiment of the present invention; Figure 5 illustrates a device for transmitting resource information about a shareable resource, according to an embodiment of the present invention; Figure 6 illustrates a method for use in a device such as the one shown in Fig. 4, according to an embodiment of the present invention; Figure 7 illustrates a method for use in a device such as the one shown in Fig. 5, according to an embodiment of the present invention; Figure 8 illustrates a first device acting as a bridging device between two other devices on different networks, according to an embodiment of the present invention; Figure 9 illustrates ranking of resources, according to an embodiment of the present invention; Figure 10 illustrates a method for determining whether a resource is currently available, according to an embodiment of the present invention; Figure ii illustrates a system including two groups of devices, according to an embodiment of the present invention; Figure 12 illustrates a method sequence chart showing a method for setting up a group io of devices, according to an embodiment of the present invention; Figure 13 ifiustrates a message sequence chart showing a method for setting up a group using authentication, according to an embodiment of the present invention; and Figure 14 illustrates a method sequence chart showing a method for reconnecting to a group using authentication, according to an embodiment of the present invention.

Detailed Description

Referring now to Fig. 1, a group of devices arranged to communicate over a network is illustrated, according to an embodiment of the present invention. In the present embodiment, the group includes a television 110-1, laptop computer 110-2, tablet computer 110-3 and smartphone 110-4. The group of devices are arranged to communicate over a wireless (WiFi) network 120, although in other embodiments any type of network, wired or wireless, could be used. Also, although certain types of device are shown in Fig. 1, in general embodiments of the present invention can include any type of device that is capable of communicating over a network with other devices.

Examples of other types of device that can be included in a group of devices similar to that shown in Fig. 1 include, but are not limited to, audio hi-fl equipment, home media servers, set-top boxes, digital versatile disc (DVD) players, and smart appliances such as fridges and washing machines that feature integrated network interfaces.

The devices 110-1, 110-2, 110-3, 110-4 within the group of devices shown in Fig. 1 are arranged to communicate over the network 120 in order to share resources between the devices 110-1, 110-2, 110-3, 110-4. In particular, a first device that has access to one or more shareable resources, which may be resources that are thcal to the first device or are accessible by the first device over the network 120, transmits resource information about the shareable resources to a second device over the network 120. For example, the television 110-1 may be arranged to share its display screen with other ones of the devices, and so may transmit resource information about the display screen over the network 120, or a camera without GPS functionality could access a GPS module being shared by a smartphone in order to obtain a GPS ocation to app'y geo-tagging to photos. The resource information can be received by one of the other devices, for example the smartphone 110-4, which can then use the resource information to request access to the display screen of the television 110-1 over the network 120. This allows the smaitphone 110-4, or any other device which receives the resource information from the television 110-1, to access the large display screen of the television 110-1. For example, the smartphone 110-4 can request access to the large display screen in order io to display a video file or still image through the tekvision 110-1.

A shareable resource can be any type of resource, for example a hardware resource such as a display, storage unit (e.g. hard disk drive), or loudspeaker, or a software resource such as a multimedia file or an application.

In general, any device in the group of devices may transmit and/or receive resource information. It is not essential for every device participating in the group of devices to share a resource. That is, any given device may only transmit resource information, only receive resource information, or both receive and transmit resource information, as required. Specifically, a device may transmit resource information if it has any resources to share, and may receive resource information if access to shareable resources is required. As an example, a device such as a media server may transmit resource information to share recorded multimedia files with other devices on the network, but may not require access itself to any shared resources and hence may not be arranged to receive any resource information from the other devices. On the other hand, a device such as a smartphone may not have any resources to share and hence may only receive resource information from other devices without transmitting any resource information itself. These scenarios are exemplary, and in other situations for example a media server may also receive resource information and/or a smartphone may also transmit resource information to share resources.

An example of resource information transmitted from one device to another is ifiustrated in Fig. 2, according to an embodiment of the present invention. In this embodiment an extended mark-up language (flIL) format is used for the resource information, but the invention is not limited to XML and in other embodiments other formats could be used. As shown in Fig. 2, the resource information 200 includes a -10-resource identifier 201 for identifying the shared resource, which is a resource accessible through the device transmitting the resource information 200, and source information for identifying a location from which the resource can be obtained.

The source information can take various forms. In the present example the source information includes a device identifier for identifying the device which supplied the resource information, and path information 202 for identifying a path through which the resource can be accessed. The device identifier is not shown in Fig. 2, but examples of device identifiers (device ID) 301,302 are shown in Fig. 3. Continuing with io reference to Fig. 2, in the present example the path information 202 specifies a directory on the device which provided the resource information. The resource can be obtained by requesting the resource from Uniform Resource Identifier (URI) obtained by combining the path information <path> with a device identifier <device ID>, for example an Internet Protocol (IP) address: <devicejD>/cpath> When a device is sharing a plurality of resources, the path information 202 can specify the location of each resource on the device. However, in some embodiments the path information can be omitted and the source information may only include the device identifier. For instance, if a device is only sharing a single resource, only the device identifier can be provided. Any other device can access the shareable resource by sending a resource access request to the device, without knowing a specific location on the device, and the device can respond to all resource access requests by providing the single shared resource.

From the point of view of the device receiving the resource information 200, the shared resource can be referred to as a remote resource, that is, a resource remote from the device and accessible over the network, as opposed to a local resource included in the device. Furthermore, in the present embodiment the resource information 200 includes authentication information 203 for identifying a type of authentication to be used when accessing the shared resource. In other embodiments however the authentication information 203 can be omitted, for example if the same authentication type will be used for all resources in the group of devices or if no authentication is to be used.

-11 -A device that receives the resource information 200 can be arranged to select one of a plurality of resources including the remote shareable resource, and if the remote resource is selected, can use the received resource information to request access to that remote resource. Various approaches are possible for selecting a resource, and wifi be described later in more detail. However, as an example, when the smartphone 110-4 of Fig. 1 is playing a multimedia file or is about to begin playback of a multimedia file, the smartphone 110-4 can determine based on received resource information that a larger display screen is available from the television 110-1, and can request a user to select whether to continue reproducing the multimedia file on the smartphone screen or on io the television screen. If the user selects the television screen, which is a remote resource shared by the television 110-1, the smartphone 110-4 requests access from the location defined by the source information 202 associated with the resource identifier of the selected remote resource, i.e. the television screen, to reproduce the multimedia file through the television.

Referring now to Fig. 3, a file format for storing received resource information is iflustrated, according to an embodiment of the present invention. In an embodiment of the present invention a device is arranged to store resource information received from different devices in a single file 300, which may be referred to as a resource catalogue.

The resource catalogue 300 can be updated whenever new resource information is received, by adding the new resource information to the catalogue file. Alternatively, in other embodiments resource information received from different devices may be stored separately. Like the embodiment of Fig. 2, an extended mark-up language (XML) format is used for the resource catalogue 300 in the present embodiment, but the invention is not limited to XML and in other embodiments other formats could be used.

As shown in Fig. 3, the resource catalogue 310 in the present example includes first resource information 300-1 received from a first device, and second resource information 300-2 received from a second device. In the resource catalogue 310 each received resource information 300-1, 300-2 is associated with a device identifier 301, 302 for identiing the device from which the resource infoimation 300-1, 300-2 was received. Specifically, the first resource information 300-1 is associated with a device identifier 301 of the first device, and the second resource information 300-2 is associated with a device identifier 302 of the second device.

-12 -Including the device identifier in the catalogue can assist in catalogue management.

For instance, in some embodiments a device can leave a group by broadcasting a leaving message over the network to be received by other devices in the group. When a device receives a leaving message, it can update its catalogue by deleting the stored resource information including the device identifier of the device from which the leaving message was received. Similarly, if updated resource information is received, a device can determine which of the resource information in the catalogue is to be replaced with the updated information based on the device identifier. Therefore the device identifier can serve two functions, namely identifying the location from which a io resource can be obtained, and enabling efficient management of stored resource information for a plurality of devices.

Referring now to Fig. 4, a device for receiving resource information about a shareable resource is illustrated, according to an embodiment of the present invention. The device 410 is able to communicate with other devices in a group of devices over the network 120, via a network interface module 412. The network interface module 412 may be included in the device 410, as shown in Fig. 4, or in other embodiments may be accessed through a separate device to which the device 410 is connected. In addition to the network interface module 412, the device 410 comprises a resource information collecting module 414 arranged to receive resource information over the network 120 from another device in the group of devices, and a selection module 416 for selecting one of a plurality of resources including the remote resource identified by the received resource information. In response to the remote resource being selected, the device is arranged to request the selected remote resource from the location identified by the source information in the received resource information. The resource information collecting module 414 can store the received resource information in a catalogue as shown in Fig. 3 or in any other format, and can store the received resource information in an internal storage module of the device 410 or in a separate storage module, for example an external hard disk drive.

By collecting resource information from other devices in the group of devices, the device 410 of Fig. 4 is able to build up a collection of information about shareable resources that can be accessed over the network 120. The device 410 can therefore select a shareable resource, for example by selecting the resource automatically when a particular condition is met or by selecting the resource in response to user input, and can request access to the resource based on the stored resource information. Because -13 -the device 410 already has the necessary infonnation required to access the resource, there is no need to provide a separate network management apparatus to store and manage data repositories for holding access information about shared resources.

Referring now to Fig. 5, a device for transmitting resource information about a shareable resource is illustrated, according to an embodiment of the present invention.

Like the device of Fig. 4, the device 510 of Fig. 5 is able to communicate with other devices in a group of devices over the network 120, via a network interface module 512 which may be included in the device 510 or accessed through a separate device. The io device further comprises a phiraUty of shareahle resources 516, and a resource information providing module 514. The resource information providing module 514 is arranged to generate the resource information including a resource identifier for identifying one of the shareable resources i6 accessible through the device and source information for identifying a location from which the resource can be obtained, and to transmit the resource information over the network 120 to other devices in the group of devices. In the present embodiment the resource information is generated whenever the device io boots up. However, in other embodiments the resource information can, for example, be generated before the device joins the group, while the device is joining the group, or after the device has joined the group and in response to a request for resource information for another device.

Furthermore, in response to a request to use the resource received from another device over the network 120, the device 510 is arranged to provide the requested resource to said other device. The device 510 may include a resource access control module for controlling access to the shareable resources 516 in response to requests received from other devices, for example if authentication of the other devices is required before access can be granted.

Various methods are possible to obtain the resource identifier to be included in the resource information. In the present embodiment, a universal'y unique identifier (UUID) is used to ensure a unique identifier for each resource. In another embodiment for example a combination of device IP address and media access control (MAC) code could be used as a resource identifier.

Although in the present embodiment the device 510 includes three shareable resources, i.e. a first shareable resource 516-1, a second shareable resource 516-2 and a third shareable resource 516-3, in general the device 510 may include any number of shareable resources, i.e. one or more shareable resources.

The devices shown in Figs. 4 and 5 codd be used as any of the devices shown in the device group of Fig. 1, and may be combined in a single device if it is required for that device to both transmit and receive resource information. Also, the separate modules shown in Figs. 4 and 5 may in general be hardware or software modules configured to perform the desired function. For example the resource information collection and generation, and resource selection, could be performed by software modules running on a processor and hence could be embodied as a computer program stored on a computer-readable storage medium, such as a hard disk, optical disk, universal serial bus (USB) memory stick, and so on.

Like to the device of Fig. 4, the device of Fig. avoids the need for a separate network management apparatus because the resource information generation and transmission is handled by the same device which is sharingthe resources. Therefore when a group of devices such as those shown in Figs. 4 and 5 exchange resource information over a network, as shown in Fig. 1, resource sharing between devices can be handled in a distributed manner without having to provide a dedicated central server for this purpose. Accordingly, even if the group of devices was originally set up by a particular device, the remaining devices can continue to share resources even after that device has left the group because resource sharing is not controlled by any single device. Hence devices can freely join and leave the group of devices at any point, without affecting the ability of the remaining devices to share resources.

Referring now to Fig. 6, a method for use in a device such as the one shown in Fig. 4 is illustrated, according to an embodiment of the present invention. The method could be implemented by dedicated hardware provided in the device, for example an application-specific integrated circuit (ASIC), or could be implemented by a computer program executed on a processor in the device.

Firsdy, in step S6oi the device receives resource information from another device in the group of devices over the network. The resource information can be information which identifies one remote shareable resource or which identifies a plurality of remote shareable resources. At this point, the device can store the received resource information, for example in a catalogue as shown in Fig. 3 together with resource -15 -information from other devices. Then, in step S6o2 one of a plurality of resources is selected, the plurality of resources including one or more local resources and the remote resource identified by the resource information received in step S6o1.

Next, in step S6o3 it is determined whether the remote resource was selected. If the remote resource was selected, then in step S6o4 the selected remote resource is requested using the location information included in the resource information received at step S6oi. On the other hand, if the selected resource was a local resource, i.e. not a remote resource being shared by another device, then in step S6o the selected local io resource is used. Although in Fig. 6 a local resource is selected, it is not essential in all embodiments for this to be the case. In some embodiments a resource may be selected only from a plurality of remote resources, i.e. a set of resources not including any local resources. For example, one of a plurality of multimedia files may be selected, all of which are stored remotely and are being shared by one or more devices over the network. In such embodiments steps S6o3 and S6o5 could be omitted and instead the process can proceed directly to step S6o4 to request the selected remote resource.

Referring now to Fig. 7, a method for use in a device such as the one shown in Fig. 5 is illustrated, according to an embodiment of the present invention. As with Fig. 6, the method of Fig. 7 could be implemented by dedicated hardware or by a computer program executed on a processor.

Firstly, in step S7o1, the device generates resource information which identifies one or more shareable resources accessible through the device. Here, the shareable resources included in the resource information could be local resources included in the device, remote resources that can be accessed by the device through another device, or any combination of local and remote shareable resources.

Then, in step S7o2, the generated resource information is transmitted to one or more other devices in the group of devices. The resource information can be broadcast to all devices, for example when the device joins the group the resource information can be broadcast over the network to all other devices in the group. Alternatively, or as well as this, the device can periodically rebroadcast resource information over the network and/or can transmit the resource information to a specific device in response to a request from that device. Also, the resource information can be generated at any point before being transmitted. In the present embodiment the resource information is generated whenever the device boots up. However, in other embodiments the resource information can, for example, be generated before the device joins the group, while the device is joining the group, or after the device has joined the group and in response to a request for resource information for another device.

After transmitting resource information, then in step 5703 the device waits to receive an access request for a shareable resource from another device in the group. In response to a request being received, the device proceeds to step 5704 and provides the resource to the requesting device. Here, authentication can be used to verify that the io request is received from an authorised device. Depending on how the group of devices has been set up, in some embodiments it may be possible to define different types of authentication for different resources, as shown in Figs. 2 and 3, or authentication may be required for all shareable resources. If authentication is required for the requested resource then the device can be arranged to authenticate the requesting device before providing the resource.

As described above, when generating resource information in step S7o1, the device can include information about remote shareable resources that are accessible from another device. This allows the device to act as a bridging device between two other devices in the group of devices, as shown in Fig. 8. In the example shown in Fig. 8, a first device 810-i is compatible with two different network standards, in this case WiFi and Bluetooth. The group of devices also includes second and third devices 810-2, 810-3 which are only compatible with WiFi and can communicate with the first device 8io-i over a WiFi network 820-i. The group of devices further includes a fourth device 810-4 which is only compatible with Bluetooth and communicates with the first device 8io-i over a Bluetooth network 820-2. In this way one group of devices can include devices that communicate over more than one network type.

In the present example the first device 8io-i can act as a bridging device between the second and third devices 810-2, 810-3, and the fourth device 810-4. Specifically, the first device 8io-i can inchide information about a remote shareabe resource on the fourth device 810-4 in the resource information sent to the second and third devices 810-2, 810-3. The second and third devices 810-2, 810-3 can therefore each access the resource on the fourth device 810-4 by sending a request to the first device 8io-i, which s will in turn request the resource from the fourth device 810-4 in order to provide the resource to the requesting device. -17-

As shown in Fig. 8, a first device can operate as a bridging device when the group includes second and third devices that are not able to communicate direcfly. However, the use of bridging devices is not limited to situations in which different network types are used. For example, even when all devices in a group communicate over the same network, a device can still act as a bridging device by including information about remote resources in its own resource information. This may be advantageous when two devices are not able to establish a reliable direct connection, since the devices can still share resources via a third device to which both can connect reliably. For instance, io environmental factors may prevent a reliable Bluetooth connection being formed direcfly between the two devices.

Embodiments of the present invention have been described in which a device can select a remote shareable resource and request access to the selected remote resource from another device in the group. To select one of a phiraUty of resources, the device can be arranged to rank the resources according to one or more predetermined ranking criteria. In particular, a phurahty of different resource types can be defined and the resource information for each resource can include type information for identifring a type of the remote shareable resource. When a resource of a particular type is required the device can rank all available resources, local and remote, of that particular type.

For example, the type of required resource may be a display screen, and the device can rank all available display screens to determine the preferred screen to use. In this way, it can be determined based on the resource information whether an alternative resource of the same type as the selected resource and having a higher ranking than the selected resource is available.

Resource ranking will now be described with reference to Fig. 9, which illustrates a system for ranking resources according to embodiments of the present invention. In the embodiment shown in Fig. 9, three rcsourccs of the same typc are ranked according to four predetermined criteria. In other embodiments, different criteria may be used.

In the present embodiment the criteria are a time since the resource was last accessed, a current state of the resource, an attribute score of the resource, and a usage history of the resource. Each resource is assigned a score in each category, and the scores for each resource are summed to give a total score. The resources can then be ranked according to their total score, with the resource with the highest score being selected as -18-the preferred resource. In some embodiments, the ranking results may be presented to a user to allow the user to select the preferred resource based on the scores.

To be able to score resources in each category, it is necessary to obtain certain information about each resource. The information for a given resource can be obtained from the device which originally provided the resource information for that resource, either by being included in the resource information initially or by being received at a later stage.

io In more detail, regarding the "last access" criteria in Fig. 9, each resource can be assigned a score under this criteria which depends on how thng it has been since the resource was last accessed. For example, a score of o may be assigned if the resource has not been accessed for more than 24 hours, a score of 1 may be assigned if the resource was accessed between iand 24 hours ago, and a score of 2 may be assigned if the resource was accessed less than 1 hour ago. These ranges are only exempthry and different ranges maybe defined for different resources, for instance a multimedia file may be accessed much less frequently than a display screen or oudspeaker.

Regarding the "resource state" criteria in Fig. 9, each resource can be scored depending on a current state of the resource, which may have different meanings for different types of resource. For example, in the case of a resource which is a global positioning system (GPS) receiver, a higher score may be assigned to the resource if the GPS receiver currently has a position fix. On the other hand, some types of resource may only have a single state, in which case this criteria may be omitted.

Regarding the "attributes" criteria in Fig. 9, this score can take into account any important attributes of the resource. Which attributes are important will depend on the resource type. For example, in the case of a display screen a higher score may be given to a arger disp'ay than a smaller display. Other examples of attributes indude, but are not limited to, whether the dispthy is colour or black-and-white, the power consumption, and the resothtion, and any combination thereof. If the resource is a loudspeaker, attributes could include maximum volume setting, power consumption lev&, and a quabty metric, and any combination thereof. In the case of a storage unit such as a hard disk drive, attributes could include access speed and available capacity.

These attributes and resource types are merely exemplary and are not limiting.

Regarding the "usage history" criteria in Fig. 9, this can be a score that is maintained by the device performing the ranking, and which takes into account such factors as whether the resource has been accessed previously, and if so, a performance levd of the resource and observed reliability. For example, if a particular resource has been accessed frequently but has proven to be unreliable, the resource may be assigned a low score under "usage history". In the example shown in Fig. 9, the third resource has not previously been accessed by the present device and hence no usage history score is available.

io As described above, resource ranking can be used to select a preferred resource when a pthrahty of different resources of the same type are available. Also, if the same resource is available through different paths, for instance can be both directly accessed and indirectly accessed through a bridging device as described with reference to Fig. 8, the resource information for each different access path, defined in the location information, can be used to rank the akernative access paths to select a preferred location from which to obtain the resource.

Referring now to Fig. 10, a method for determining whether a resource is currently available is illustrated, according to an embodiment of the present invention. In this embodiment, before selecting one of a plurality of resources a device is arranged to query the devices providing the plurality of resources to determine whether each resource is currently available. Unavailable resources can be removed from the selection process to ensure that only available resources can be selected.

The method shown in Fig. 10 can be performed either at the device which provides the resource, before responding to the availability query with a simple response indicating yes' or no' for availability, or can be performed at the device making the selection based on information received in response to the query.

In more detail, the example shown in Fig. 10 iflustrates different availability states of five resources. A first resource, 001, is dassed as unavailable because the device providing the resource is not currenfly present, i.e. has eft the network. A second resource, 002, is available because the device is present and the resource is not currently in use. A third resource, 003, is available because although the resource is currently in used, the resource supports parallel use, i.e. use by more than one device at a time. For example, parallel use may be supported by a media file, but not by a display screen. A fourth resource, 004, is available because the resource is intemiptible and the requesting device has a high priority. In this case it is irrelevant whether the resource is currenfly in use because the requesting device wifi be able to interrupt the resource to obtain access. Finally, a fifth resource, 005, is unavailable because the resource is in use, parallel use is not supported, and the requesting device is not permitted to interrupt the previous user of the resource.

Referring now to Fig. 11, a system including two groups of devices is illustrated, according to an embodiment of the present invention. Specifically, in the present Jo embodiment there are five devices 1110-1, 1110-2, 1110-3, 1110-4, 1110-5 all arranged to communicate via the same network 1120. However, not all of the devices are included in the same group. The first 1101-1, second 1110-2, and third 1110-3 devices are included in a first group 1131, whilst the third device 1110-3 is also part of a second group 1132 which includes the fourth 1110-4 and fifth devices 1110-5. The different is groups can be defined by different group identifiers (IDs). A group ID is shown in Fig. 3, where the resource cata'ogue indudes a GROUP ID to identify the group to which the resource information applies. In the case of the third device 1110-3 in Fig. ii, this device could store separate resource catalogues for the first 1131 and second 1132 groups under different group IDs.

Defining different groups in this way enables different resources to be shared across different groups. For instance, the third device 1110-3 can share certain resources with the first group 1131 by sending resource information for those resources to the other devices 1110-1, 1110-2 in the first group 1131. Similarly, the third device 1110-3 can also share a different set of resources with the other devices 1110-4, 1110-5 in the second group 1132. This may be particularly advantageous when, for example, one group is set up to use authentication and the other group is set up as an open group which does not require authentication.

Referring now to Fig. 12, a method sequence chart showing a method for selling up a group of devices is iflustrated, according to an embodiment of the present invention.

To set up a new group of devices, i.e. if the group of devices does not afready exist, a first device 1210-1 broadcasts a group setup message over a network 1220.

In more detail, a device can be arranged to attempt to join or set-up a group of devices whenever a predetermined condition is met. In the present embodiment, the predetermined condition is based on location awareness, and the first device 1210-1 is arranged to periodically obtain information about its location, for example using a GPS receiving modifie. Akemativ&y, in other embodiments the ocation determination may be made based on a WiFi signal, by determining that the device is within range of a predetermined network, or using other information such as ambient sound detection.

In response to the location information indicating that the device is at a predetermined location, the first device 1210-1 is arranged to determine whether the group of devices exists by broadcasting a group search message including a predetermined group identifier for identifying the group, waiting a predetermined time, and determining that io the group does not exist if a response indicating the existence of the group is not received from the network within the predetermined time. This approach ensures that other devices on the network are not required to respond unless they are already part of the identified group, reducing a network traffic burden. In other embodiments however, instead of broadcasting a message including the predetermined group ID, the first device can be arranged to broadcast a group search message to request other devices to respond with the group IDs of any existing groups to which they afready b&ong. The first device can then wait a predetermined time and compare the group IDs in any responses received in that time against the predetermined ID, to determine whether the group exists.

Continuing with reference to Fig. 12, the group setup message is received by a second device 1210-2 that is also connected to the network 1210-2. In response to the group setup message, the second device 1210-2 determines whether to join the new group.

For example, the second device 1210-2 may request a user to select whether or not to join the group, or alternatively could be arranged to automatically join any new group meeting certain criteria, for instance any new open' group that does not require authentication.

If it is determined to join the new group, the second device 1210-2 transmits a response message to the first device 1210-1 to confirm that the second device 1210-2 intends to join the group. Then, the first device 1210-1 requests resource information from the second device 1210-2, receives the resource information from the second device 1210-2, and in response transmits its orn resource information to the second device 1210-2. At this point both devices 1210-1, 1210-2 have exchanged resource information and can now share their resources, and the group is set up. -22-

Although in Fig. 12 a dedicated response to the group setup message is transmitted, and a dedicated request for resource information is transmitted, in some embodiments these can be omitted. For example, instead of responding to the group setup message with a dedicated response, the second device could simply respond by transmitting the resource information to the first device.

Referring now to Fig. 13, a message sequence chart showing a method for setting up a group using authentication is illustrated, according to an embodiment of the present invention. The method is similar in some respects to the method of Fig. 12, and a io detailed description of the similar steps will be omitted here to maintain brevity. In the present embodiment, the group setup message broadcast by the first device 1310-1 over the network 1320 includes authentication information that identifies a type of authentication to be used in communications between devices in the new group. Upon receipt of the group setup message, the second device 13 10-2 requests to join the new group by starting a mutua' authentication with the first device 1310-1. In response to the message from the second device 1310-2 being successfully authenticated by the first device 1310-1, the first device 1310-1 accepts the joining request from the second device 1310-2 and transmits an authorisation token to the second device 1310-2. The authorisation token is a token for use in authenticating communications between devices in the same group, which can be included in messages sent over the network to verify to a device receiving the message that it originated from an authorised device.

The second device 1310-2 stores the authorisation token.

As shown in Fig. 13, when subsequently requesting the resource information from the second device 1310-2, the first device 1310-1 is now arranged to include the authorisation token in the request message. The second device 1310-2 is therefore able to confirm, by comparison with the stored token, that the request message originated from an authorised device.

Referring now to Fig. 14, a message sequence chart showing a method for reconnecting to a group using authentication is illustrated, according to an embodiment of the present invention. In the present example, a second device 1410-2 is reconnecting to a network to which a first device 1410-1 and a third device 1410-3 are connected. The second device 1410-2 was previously connected to the network and was a member of group 1, to which the first device 1410-1 also belongs. The third device 1410-3 is not included in group 1, but is a member of a second group 2.

-23 -Upon reconnecting the network, the second device 1410-2 broadcasts a group search message to determine whether group 1 still exists, i.e. whether any devices included in group 1 are still connected to the network. In the present examp'e the group search message requires each device to respond with the group IDs of any groups to which it belongs, although as described above, other approaches are possible in other embodiments. The first device 1410-1 responds with a message including the group ID of the first group, and the third device 1410-3 responds with a message including the group ID of the second group. At this point, the second device 1410-2 that group istill io exists because the first device 1410-1 is still connected to the network. In response to the determination that the group exists, the second device 1410-2 broadcasts a request to any devices in the first group to rescan the group, to prompt each device to update its catalogue with the shared resources of the second device 1410-2.

In the present embodiment, group 1 is set up to use an authorisation token to authenticate communications, as described above wIth reference to Fig. 13. Therefore the first device 1410-1, and any other devices in group 1 still connected to the network, respond to the rescan request by sending a resource information request including the authorisation token to the second device 1410-2. Because the second device 1410-2 was previously part of the first group, the second device 1410-2 already has the authorisation token and can confirm that the request from the first device 1410-1 originated from an authorised device. Therefore the second device 1410-2 transmits its own resource information to the first device 1410-1, which adds the resource information to its own catalogue. A similar message sequence follows for the second device 1410-2 to receive resource information from the first device 1410-1. At this point the second device 1410-2 has now rejoined the first group and can resume sharing resources.

Embodiments of the present invention have been described in which devices receive resource information about shareable resources that are accessible through other devices on a network. In some embodiments, a device can be arranged to store the received resource information for a predetermined time period and request updated resource information from the other device after the predetermined time period has expired. This ensures that an up-to-date record of shareable resources can be maintained. Also, in response to updated resource information not being received, the device can be arranged to delete the stored resource information for the other device.

-24 -This ensures that when a device leaves the network, other devices do not subsequently attempt to access that device's shareable resources.

Whilst certain embodiments of the present invention have been described above, the skilled person will appreciate that many variations and modifications are possible without departing from the scope of the invention as defined in the accompanying claims.

Claims

-25 -Claims 1. A device for communicating over a network wIth one or more other devices within a group of devices, the device comprising: a resource information collecting module arranged to receive resource information from one of the other devices, the resource information including a resource identifier for identifying a remote resource accessible through the other device and source information for identifying a location from which the remote resource can be obtained; and a se'ection modide for sdecting one of a phirahty of resources inchiding the remote resource, wherein in response to the remote resource being selected, the device is arranged to request the selected remote resource from the location identified by the source information.
2. The device of chnim 1, wherein prior to receiving the resource information the device is arranged to determine whether the group of devices exists and to request the resource information from the one or more other devices if the group of devices exists, or set up the group of devices if it does not exist, and wherein the device is arranged to set up the group of devices by broadcasting a group setup message over the network to invite the other devices to join the group.
3. The device of claim 2, wherein after broadcasting the group setup message the device is arranged to respond to a request from one of the other devices to join the group by authenticating said one of the other devices, and transmitting an authorisation token to said one of the other devices in response to a successful authentication result, the authorisation token comprising a token for use in authenticating communications between devices in the same group.
4. The device of daim 2 or 3, wherein the device is arranged to determine whether the group of devices exists by broadcasting a group search message inchiding a predetermined group identifier for identifying the group, waiting a predetermined time, and determining that the group does not exist if a response indicating the existence of the group is not received from the network within the predetermined time.

-26 -
5. The device of claim 2,3 or 4, further arranged to obtain location information about a current location of the device, wherein the device is arranged to determine whether the group of devices exists in response to the location information indicating that the device is at a predetermined location.
6. The device of any one of the preceding claims, wherein prior to receiving the resource information the device is arranged to broadcast a resource information request including a predetermined group identifier for identifying the group of devices, io to request resource information from any devices on the network that are included in the group.
7. The device of any one of the preceding claims, wherein when resource information for a plurality of resources is received the device is arranged to determine based on the received resource identifiers whether one of the resources can be obtained from a phirality of different ocations, and wherein in response to the selection module selecting said one of the resources, the device is arranged to select a preferred one of the plurality of different locations from which to request the resource based on predetermined criteria.
8. The device of any one of the preceding claims, wherein the selection module is arranged to rank the plurality of resources according to one or more predetermined ranking criteria, before selecting one of the resources.
9. The device of claim 8, wherein the selection module is arranged to rank the plurality of resources based on, for each one of the plurality of resources, information about: a time since the resource was last accessed; and/or a current state of the resource; and/or an attribute score of the resource; and/or a usage history of the resource.
10. The device of daim 8 or 9, wherein the resource information includes type information for identifying a tpe of the remote resource, and wherein in response to the selection module selecting one of the resources, the device is arranged to determine based on the resource information whether an -27-alternative resource of the same type as the selected resource and having a higher ranking than the selected resource is available.
ii. The device of any one of the preceding claims, wherein the device is further arranged to transmit local resource information to the one or more other devices in the group over the network, the local resource information comprising information about a resource accessible through the device.
12. The device of any one of the preceding claims, wherein the device is arranged to io store the received resource information for a predetermined time period and request updated resource information from the other device after the predetermined time period has expired, and wherein in response to updated resource information not being received, the device is arranged to delete the stored resource information for the other device.
13. The device of any one of the preceding claims, wherein the selection module is arranged to s&ect one of the phirabty of resources in response to user input, by providing a user with information about the plurality of resources and receiving a user command se'ecting one of the plurality of resources.
14. A device for communicating over a network with one or more other devices within a group of devices, the device comprising: a resource information providing module arranged to generate resource information including a resource identifier for identifying a resource accessible through the device and source information for identifying a location from which the remote resource can be obtained, and to transmit the resource information to the one or more other devices over the network, wherein in response to a request to use the resource received from one of the other devices, the device is arranged to provide the requested resource to said one of o the other devices.
15. The device of daim 14, arranged to communicate over a first network according to a first network protoc& and to communicate over a second network according to a second network protocol, wherein the group of devices includes a first other device on the first network and a second other device on the second network, and wherein in response to a request for resource information from the first other device, the resource information providing module is arranged to transmit resource information about a remote resource provided by the second other device and accessible through the device.
16. The device of claim 15, wherein in response to a request from the first other device to access the remote resource, the device is arranged to request the remote resource from the second other device to provide the remote resource to the first other device. I017. The device of cthim 14, 15 or 16, wherein the request received from said one of the other devices includes a group identifier for identifying the group of devices, and wherein the device is arranged to determine whether authentication is required in the identified group, and in response to a determination that authentication is required, the device is arranged to authenticate said one of the other devices before providing the requested resource.18. A network comprising: at least one device according to any one of claims ito i; and at least one device according to any one of claims 14 to
17.19. The network of claim i8, wherein one of the devices according to any one of claims ito 13 and one of the devices according to any one of claims 14 to 17 are embodied in the same device.20. A method for use in a device for communicating over a network with one or more other devices within a group of devices, the method comprising: receiving resource information from one of the other devices, the resource information including a resource identifier for idcntidng a remote resource acccssibk through the other device and source information for identifying a location from which the remote resource can be obtained; selecting one of a p'urality of resources including the remote resource; and requesting the selected remote resource from the ocation identified by the source information, in response to the remote resource being selected.-29 - 21. The method of claim 20, further comprising prior to receiving the resource information: determining whether the group of devices exist; requesting the resource information from the one or more other devices if the group of devices exists; and setting up the group of devices if it does not exist, by broadcasting a group setup message over the network to invite the other devices to join the group.22. The method of claim 21, further comprising after broadcasting the group setup io message: responding to a request from one of the other devices to join the group by authenticating said one of the other devices; and transmitting an authorisation token to said one of the other devices in response to a successful authentication result, the authorisation token comprising a token for use in authenticating communications between devices in the same group.23. The method of claim 21 or 22, wherein determining whether the group of devices exists comprises: broadcasting a group search message including a predetermined group identifier for identiIring the group; waiting a predetermined time; and determining that the group does not exist if a response indicating the existence of the group is not received from the network within the predetermined time.24. The method of claim 21,22 or 23, further comprising: obtaining location information about a current location of the device; wherein it is determined whether the group of devices exists in response to the location information indicating that the device is at a predetermined location.25. The method of any one of daims 20 to 24, further comprising prior to receiving the resource information: broadcasting a resource information request including a predetermined group identifier for identifying the group of devices, to request resource information from any devices on the network that are included in the group.26. The method of any one of claims 20 to 25, wherein when resource information for a plurality of resources is received, the method further comprises: determining based on the received resource identifiers whether one of the resources can be obtained from a phirabty of different locations; and selecting a preferred one of the plurality of different locations from which to request the resource based on predetermined criteria, in response to said one of the resources being selected.27. The method of any one of claims 20 to 26, further comprising: Jo ranking the pluraBty of resources according to one or more predetermined ranking criteria, before selecting one of the resources.28. The method of claim 27, wherein the plurality of resources are ranked based on, for each one of the plurality of resources, information about: a time since the resource was thst accessed; and/or a current state of the resource; and/or an attribute score of the resource; and/or a usage history of the resource.29. The method of claim 27 or 28, wherein the resource information includes type information for identifying a type of the remote resource, the method further comprising: determining based on the resource information whether an alternative resource of the same type as the selected resource and having a higher ranking than the selected resource is available, in response to said resource being selected.30. The method of any one of claims 20 to 29, further comprising: transmitting local resource information to the one or more other devices in the group over the network, the local resource information comprising information about a resource accessible through the device.31. The method of any one of daims 20 to 30, further comprising: storing the received resource information for a predetermined time period; requesting updated resource information from the other device after the predetermined time period has expired; and deleting the stored resource information for the other device, in response to updated resource information not being received.32. The method of any one of daims 20 to 31, wherein sdecting one of the plurality of resources comprises: providing a user with information about the plurality of resources; and receiving a user command selecting one of the plurality of resources.33. A method for use in a device for communicating over a network with one or more other devices within a group of devices, the method comprising: generating resource information inchiding a resource identifier for identifying a resource accessible through the device and source information for identifying a location from which the remote resource can be obtained; transmitting the resource information to the one or more other devices over the network; receiving a request to use the resource from one of the other devices; and providing the requested resource to said one of the other devices.34. The method of claim 33, wherein the device is arranged to communicate over a first network according to a first network protocol and to communicate over a second network according to a second network protocol, wherein the group of devices includes a first other device on the first network and a second other device on the second network, and wherein in response to a request for resource information from the first other device, resource information about a remote resource provided by the second other device and accessible through the device is transmitted to the first other device.35. The method of eiaim 34, further comprising: requesting the remote resource from the second other device to provide the remote resource to the first other device, in response to a request from the first other device to access the remote resource.36. The method of claim 33,34 or 35, wherein the request received from said one of the other devices includes a group identifier for identifying the group of devices, the method further comprising: determining whether authentication is required in the identified group; and authenticating said one of the other devices before providing the requested resource, in response to a determination that authentication is required.37. A computer-readable storage medium arranged to store a computer program which, when executed, performs a method according to any one of claims 20 to 36.