The present invention relates to audio visual content and to its distribution.

Examples of the present invention are particularly applicable in the field of advertising, but are not limited to that application. One conventional form of advertising uses large, printed posters which are fixed to billboards located in prominent positions, so that the advertisement is visible to passers-by, motorists etc. The advertiser makes a payment for the poster to be displayed. The owner of the billboard is paid for allowing the poster to be displayed. In order to change the poster, a workman must visit the billboard in order to paste a new poster onto the billboard. The poster cannot otherwise be changed and will therefore remain unchanged for a considerable period, perhaps several weeks or months.

More recently, rotating billboards have been used. These have rotating elements, such as triangular cylinders. A drive arrangement periodically turns all of the cylinders together. This allows three different advertisements to be displayed by attaching strips of each advertisement to a corresponding face of each cylinder. A change of advertisement is achieved by visiting the site and attaching a new poster to the rotating elements, which is a time consuming task. Thus, although a rotating billboard is able to display the three advertisements in sequence, the sequence is not readily changed and thus tends to remain the same for a considerable period of time. If the rotating mechanism fails, an advertiser may have been charged but received no exposure for their advertisement.

In each of these examples, the advertisement is embodied as a physical article (a poster) at the billboard location. More recently, electronic billboards have been used to display a message in the form of an image on

an electronic screen. This displays a transient image created locally, making it difficult to prove to an advertiser that a paid advertisement has been displayed, or that the electronic billboard has been working at all.

The present invention provides a system for distributing audio visual content to a plurality of locations for display at those locations, comprising:

a plurality of stations which, in use, display content; a server arrangement in communication with the stations and which stores, in use, information for each station, defining a pre-arranged sequence of content to be displayed by the station; wherein each station is operable to create a display of content identified by information received from the server arrangement; to send a request to the server arrangement to identify the requesting station and to request information defining further content in the sequence corresponding with the requesting station; and to identify to the server the content which has been displayed; and the server arrangement being operable to receive requests from stations, to consult the sequence information to identify further content from the sequence corresponding with the requesting station, and to send to the requesting station information defining the identified content.

Preferably, the server responds to each request to identify the next step in the corresponding sequence. The stations preferably identify the sequence step which has been displayed immediately previously.

The server arrangement may store billing information relating to payments due to the proprietor of the location of the stations for displaying at least some of the steps of at least some of the sequences, and is operable to update billing information in response to station requests which identify content which has been displayed. The billing information may include tariff

information by which payments due to the proprietor are determined, at least in part, by the identity of the station. The tariff information may contain information about attributes of the stations, and user-identified desired profiles of attributes for stations, whereby content may be included in the sequence for a station only in accordance with the result of a comparison between the attributes of the station and the desired profile. The tariff information may determine the payment to be offered to a station in accordance with the result of the comparison.

The server arrangement is preferably operable to allow authorised access to the database of chargeable content, to allow content to be changed. The server arrangement may be operable to allow authorised access by a user who will be charged for the display of chargeable content. The database may be operable by a user to create new chargeable content for inclusion as a step in content sequences.

The server arrangement is preferably also operable to allow authorised access to the sequence information, for modification. Access to the sequence information for modification may be restricted to the proprietor of the location of the station with which the sequence information corresponds. The server arrangement is preferably operable by the proprietor to create new content and/or new content sequences. The server arrangement preferably maintains, in use, a database of content for which charges are due when displayed at a station, and is operable for a proprietor to select chargeable content for inclusion in a contents sequence. The database is preferably operable to provide a proprietor with the charging information during selection.

The server arrangement may identify further content to a station by reference to content stored elsewhere. At least some of the stations may be in communication in a peer-to-peer network which includes storage for content, whereby the server arrangement may identify further content to a

station by reference to content stored in a peer-to-peer network of which a requesting station forms part. Information identifying further content may include content to be stored in a peer-to-peer network for future use.

Preferably at least one station includes a plurality of display devices at respective locations.

Preferably at least one station is associated with an image capture device operable to capture an image being displayed by the station in response to sequence information from the server arrangement, the device being further operable to transmit the captured image to the server arrangement for storage.

Preferably, each content sequence includes a sequence of images for display. Each image may include still images and/or text and/or video images.

The invention also provides a server arrangement for use in a system for distributing audio visual content to a plurality of locations for display at those locations by stations at those locations, the server arrangement being operable to communicate with stations at the said locations and to store, in use, information for each station, defining a pre-arranged sequence of content to be displayed by the station; the arrangement being further operable to receive requests from stations, requesting information defining further content in the sequence corresponding with the requesting station and identifying content which is being displayed; and the server arrangement being further operable to consult the sequence information in response to a request, to identify further content from the sequence corresponding with the requesting station, and to send to the requesting station information defining the identified content.

Preferably, the server responds to each request to identify the next step in the corresponding sequence. The requests preferably identify the sequence step which has been displayed immediately previously.

The server arrangement may store billing information relating to payments due to the proprietor of the location of the stations for displaying at least some of the steps of at least some of the sequences, and is operable to update billing information in response to station requests which identify content which has been displayed. The billing information may include tariff information by which payments due to the proprietor are determined, at least in part, by the identity of the station. The tariff information may contain information about attributes of the stations, and user-identified desired profiles of attributes for stations, whereby content may be included in the sequence for a station only in accordance with the result of a comparison between the attributes of the station and the desired profile. The tariff information may determine the payment to be offered to a station in accordance with the result of the comparison.

The server arrangement is preferably operable to allow authorised access to the database of chargeable content, to allow content to be changed. The server arrangement may be operable to allow authorised access by a user who will be charged for the display of chargeable content. The database may be operable by a user to create new chargeable content for inclusion as a step in content sequences.

The server arrangement is preferably also operable to allow authorised access to the sequence information, for modification. Access to the sequence information for modification may be restricted to the proprietor of the location of the station with which the sequence information corresponds. The server arrangement is preferably operable by the proprietor to create new content and/or new content sequences. The server arrangement preferably

maintains, in use, a database of content for which charges are due when displayed at a station, and is operable for a proprietor to select chargeable content for inclusion in a contents sequence. The database is preferably operable to provide a proprietor with the charging information during selection.

The server arrangement may identify further content to a station by reference to content stored elsewhere. At least some of the stations may be in communication in a peer-to-peer network which includes storage for content, whereby the server arrangement may identify further content to a station by reference to content stored in a peer-to-peer network of which a requesting station forms part. Information identifying further content may include content to be stored in a peer-to-peer network for future use.

The invention also provides a station for displaying audio visual content distributed to a plurality of locations from a server arrangement, for display at those locations, the station being operable to create a display of content identified by information received from the server arrangement; to send a request to the server arrangement to identify the requesting station and to request information defining further content in the sequence corresponding with the requesting station; and to identify to the server the content which has been displayed.

The stations preferably identify the sequence step which has been displayed immediately previously.

The station may include a plurality of display devices at respective locations.

The station may be associated with an image capture device operable to capture an image being displayed by the station in response to sequence

information from the server arrangement, the device being further operable to transmit the captured image to the server arrangement for storage.

The invention also provides a method for distributing audio/visual content to a plurality of locations for display at those locations, comprising:

storing information on a server arrangement remote from the locations, the information defining a pre-arranged sequence of content to be displayed by each station; receiving, at the server arrangement, a request identifying a requesting station and requesting information defining further content in the sequence corresponding with the requesting station and identifying content which has been displayed; consulting the sequence information stored at the server arrangement to identify further content from the sequence corresponding with the requesting station; sending from the server arrangement to the requesting station information defining the identified content, and receiving the information at the requesting station; and creating at the requesting station a display of content identified by information received from the server arrangement.

Preferably, the server responds to each request to identify the next step in the corresponding sequence. The stations preferably identify the sequence step which has been displayed immediately previously.

The server arrangement may store billing information relating to payments due to the proprietor of the location of the stations for displaying at least some of the steps of at least some of the sequences, and updates billing information in response to station requests which identify content which has been displayed. Billing information may be updated by reference to tariff

information by which payments due to the proprietor are determined, at least in part, by the identity of the station. The tariff information may contain information about attributes of the stations, and user-identified desired profiles of attributes for stations, whereby content may be included in the sequence for a station only in accordance with the result of a comparison between the attributes of the station and the desired profile. The tariff information may determine the payment to be offered to a station in accordance with the result of the comparison.

Authorised access to the database of chargeable content may be allowed, to allow content to be changed. Authorised access may be allowed for a user who will be charged for the display of chargeable content. The database may be operable by a user to create new chargeable content for inclusion as a step in content sequences.

Authorised access to the sequence information may be allowed, for modification. Access to the sequence information for modification may be restricted to the proprietor of the location of the station with which the sequence information corresponds. The server arrangement is preferably operable by the proprietor to create new content and/or new content sequences. A database is preferably maintained of content for which charges are due when displayed at a station, and a proprietor may select chargeable content for inclusion in a contents sequence. The database preferably provides a proprietor with the charging information during selection.

The server arrangement may identify further content to a station by reference to content stored elsewhere. At least some of the stations may be in communication in a peer-to-peer network which includes storage for content, whereby the server arrangement may identify further content to a station by reference to content stored in a peer-to-peer network of which a

requesting station forms part. Information identifying further content may include content to be stored in a peer-to-peer network for future use.

Preferably an image capture device is used to capture an image being displayed by the station in response to sequence information from the server arrangement, the captured image being transmitted to the server arrangement for storage.

The invention also provides a method for distributing audio/visual content to a plurality of locations for display at those locations, comprising:

storing information on a server arrangement remote from the locations, the information defining a pre-arranged sequence of content to be displayed by each station; receiving, at the server arrangement, a request identifying a requesting station and requesting information defining further content in the sequence corresponding with the requesting station and identifying content which has been displayed; consulting the sequence information stored at the server arrangement to identify further content from the sequence corresponding with the requesting station; sending from the server arrangement to the requesting station information defining the identified content.

The invention also provides a method for displaying audio/visual content by means of a display station at a location, comprising:

storing information on a server arrangement; sending, from the display station to a server arrangement remote from the location, a request identifying the requesting station and requesting

information defining further content in the sequence corresponding with the requesting station and identifying content which has been displayed; receiving from the server arrangement information defining the identified content; and creating at the requesting station a display of content identified by information received from the server arrangement.

Embodiments of the present invention will now be described in more detail, by way of example only, and with reference to the accompanying drawings, in which:

Fig. 1 is a schematic diagram of a system according to the present invention;

Figs. 2 and 3 are schematic views of graphical user interfaces for use by advertisers using the system of Fig. 1 ;

Fig. 4 is a schematic view of a graphical user interface for use by a proprietor of a station displaying advertising;

Figs. 5a and 5b are schematic diagrams of sequences of content for display;

Fig. 6 is a flow diagram of the process of displaying sequences; and

Figs. 7a and 7b are diagrams of fields in messages propagating in the system of Fig. 1 , during use.

Overview

Fig. 1 is a schematic diagram of a system according to the present 5 invention. The system 10 is for distributing audio visual content for display, such as advertisements. The term "audio visual" is used to make clear that the content may include images and/or sounds but it is to be understood that it is not necessary for every element of the content to include both types of component. I O

The system 10 distributes audio visual content to a plurality of locations 12 for display at those locations.

A plurality of stations 14 display content, in use. A server arrangement

15 16 is in communication with the stations 14. The server 16 stores, generally at 18, information for each station 14, defining a pre-arranged sequence of content to be displayed by the station 14. Each station 14 operates to create a display at 20 of content identified by information received from the server

16. The stations 14 also send requests to the server 16 to identify the 0 requesting station and to request information defining further content in the sequence corresponding with the requesting station 14. The stations 14 also identify to the server 16 the content which has been displayed. The server 16 receives these requests from stations 14, consults the sequence information at 18 to identify further content from the sequence corresponding with the 5 requesting station 14, and sends to the requesting station information defining the identified content.

Structure of Server

0 The server 16 is a data processing machine having an operating system 16A supporting various application software and memory functions in the region 16B and which may be embodied as software, hardware or

firmware, or combinations. The storage function 18 is preferably in the form of a database and which includes a range of different types of information, illustrated here as separate databases within the store 18. A sequence database 22 stores pre-arranged sequences of content. A billing database 24 stores tariff and billing information which is updated as sequences are executed. A chargeable content database 26 stores content representing paid advertising, from which sequences can be constructed. A self-generated content database 28 contains content which is not paid advertising, from which sequences can be constructed. An attribute database 30 stores information relating to attributes of the stations 14. A captured image database 32 stores images captured at the stations 14.

The server 16 also includes an input/output function 34 by means of which the server 16 is in communication with a data communication network such as the internet 36, for communication with stations 14. This allows the stations 14 to gain access to the database 18 through the input/output function 34, at 38. The function 34 incorporates a security function 40, to prevent unauthorised access.

Structure of Stations

The stations 14 each include at least one display 20. In a simple example, the station 14A includes a single display 20 with appropriate local processing functions 42 by means of which the display 20 is controlled, and by means of which the station 14A communicates externally, at 44. The display 20 may include a loudspeaker or other arrangement for reproducing sound. The station 14A is in direct communication with an internet service provider (ISP) 46, through which communication is established with the internet and thus with the server 16. It is envisaged that the station 14A will be located at the premises of a proprietor, such as a retail establishment or other commercial venue. The purpose of the display is to display sequences

of audio visual content, which may include advertising material for which the proprietor of the station 14 will be paid.

5 Another station 14B is more complex, including several displays 20.

These may be at different locations controlled by a single proprietor, such as different locations within a single venue, or at different venues, such as different branches of the proprietor's business. Thus, a single proprietor, or a linked group of proprietors control all of the locations of the displays 20, which

I O can therefore be considered as a single station. The station 14B includes local processing at 42 which may be common to all of the displays 20 of the station. In addition, or alternatively, each display 20 may be provided with a processing function for display control. The station 14B is connected at 44 to the same ISP 46 as the station 14A. The station 14B also incorporates

15 memory 48. Accordingly, the stations 14A, 14B can operate as a peer-to-peer network through the ISP 46, with the memory 48 providing network memory for the peer-to-peer network and thus able to be used as cache memory for the peer-to-peer network.

0 Proprietors of the stations 14 have machines 50 for communication with the ISP 46 and thereby with the internet 36 and the server 16. Only one proprietor machine 50 is illustrated, for simplicity.

Fig. 1 also illustrates third and fourth stations 14C, 14D connected to a 5 second ISP 52 for communication through the internet 36 with the server 16, and thus forming a second peer-to-peer network through the ISP 52. The stations 14C, 14D may have the structure of the stations 14A or 14B and are therefore not described or illustrated in detail.

0 Advertisers who wish to pay for advertising material to be displayed at the displays 20 use advertiser machines 54 to communicate with the server 16 (through an ISP 55). In particular, the machines 54 communicate with the

chargeable content database 26 and the tariff part of the billing database 24, as will be described.

5 Placing Advertisements

The interaction of an advertiser machine 54 with the server 16 is primarily with the chargeable content database 26 and the billing database 24, and optionally with the attribute database 30. Interaction is preferably by

I O means of a graphical user interface (GUI) 56 (Fig. 2) generated within the input/output function 34. The advertiser GUI 56 provides the advertiser with a screen display having a region 58 on which the content which is being created is displayed, and a region 60 illustrating tools accessible to the advertiser by appropriate cursor control, for use in creating the advertising content. The

15 tools at 60 may include a tool 6OA for inserting still images 62A, a tool 6OB for inserting video images 62B, a tool 6OC for inserting text 62C and other tools 6OD for other forms of manipulation of the advertising content. In use, an advertiser uses the tools 60 to manipulate the advertising content in the region 58 until that is satisfactory, and then saves the content into the 0 chargeable content database 26. The tools 60 also include a tariff tool 6OE which opens a tariff menu 64 which provides a function 66A for interaction with the billing database 24, and optionally a function 66B for interaction with the attribute database 30. The tariff/billing function 66A allows data to be entered into the tariff area of the billing database 24, indicating the amount 5 which the advertiser is prepared to pay for the display at a station 14 of the advertising content which has been created with the GUI 56. This tariff may depend on the length of time for which the content is displayed, the time of day and other factors. In particular, function 66B allows tariff payments to be dependent on station attributes stored in the attribute database 30. Thus, the 0 function 66B allows the advertiser to select a desired profile of attributes for a station, in order to allow stations which meet that profile, or exceed a minimum profile requirement, to display the advertising content and be paid

for displaying it, and to indicate that the advertising content should not be displayed at stations which do not meet the desired profile or minimum profile requirement. 5

In order to allow profiles to be created for this reason, the attribute database 30 may include information about a range of attributes of the stations 14, such as their location, the identity or business type of the proprietor of the station 14, the nature of the business or premises in which I O the station 14 is located, the expected number of viewers (which will depend on the prominence of the location etc.) and other attributes.

Accordingly, after an advertiser has created and stored advertising content, the content is in the chargeable content database 26 and is I 5 associated with tariff data in the billing database 24, which may incorporate references to profiles of attributes stored in the attribute database 30.

It is to be particularly noted that in communicating with the server 16, the advertiser does not order the display of specific advertising content at 0 specific displays or stations.

Creation of Sequences of Display Content

The proprietors of stations 14 are also in communication with the 5 server 16, as has been described. This communication is principally to interact with the chargeable contents database 26, the billing database 24, the self-generated content database 28 and the sequence database 22.

Interaction is preferably achieved by means of a GUI 68 (Fig. 4). This provides access to tools at 70, by a cursor control device, in order to create a 0 sequence of display content indicated in the main display region 72. A tool

7OA provides access to the chargeable content database 26. This allows the proprietor to view advertising content which advertisers have loaded to the

database 26, including details of displayed images and tariff rates. Access to this content is filtered by the database 26 by reference to any attribute profile requirements set by the advertiser, so that a proprietor does not have access to advertising content which is inappropriate in view of the attribute profile of the proprietor's station 14. The tool 7OA allows the proprietor to select from the available advertising content. This selection may be influenced by the payment available, by a desire not to advertise competing products, or other commercial factors. When an item of advertising content has been selected, a corresponding image 74 appears in the display region 72.

A second tool 7OB provides interaction with the self-generated content database 28. This allows a station proprietor to design additional display content, preferably by means of a GUI acting in the manner of the GUI 56 described above, or to select existing content from a library contained in the database 28. For example, a proprietor may create an item of display content which relates to a current promotion being undertaken at the proprietor's station. When an item of display content has been created by the proprietor, it is saved to the self-generated content database 28 and if selected for the current sequence, a corresponding image 74 appears in the region 72.

Accordingly, the tools 7OA, 7OB allow the proprietor to interact with the databases 26, 28 to create a sequence of display content from the advertising content offered to the proprietor by means of the chargeable content database 26, and from the library of self-generated content in the database 28. The proprietor has the opportunity to design the sequence for maximum benefit. For example, revenue from chargeable content can be maintained by selection of high-paying content, or many items of chargeable content. Alternatively, self-generated and chargeable content can be formed into a sequence which increases consumer interest and sales.

A sequence attribute tool 7OC allows the proprietor to allocate attributes to the sequence being created, such as a name, date or time during which the sequence is to be used etc. 5

When the design of the sequence has been completed, it is saved to the sequence database 22.

Two examples of sequences created in this way are illustrated I O schematically in Figs. 5a and 5b. The sequence of Fig. 5a has four steps corresponding with four items of display content. These are hereafter referred to as "slides" by analogy with a sequential display of photographic slides but, as noted above, each slide may incorporate still images, video images, text and/or sound. The sequence of Fig. 5a incorporates four slides, including one 15 slide 76 of advertising content and three slides 78 which have been self- generated. This sequence might, for example, be selected for display during trading hours of the station 14, so that the slides 78 can relate to current promotions being undertaken by the station proprietor.

0 The sequence of Fig. 5b includes five slides, four of which 80 are advertising content and one of which 82 is self-generated. This sequence might, for example, be selected for display when the business at the station 14 is closed, so that advertising is provided for passers-by and the station proprietor can achieve an income (for displaying the advertising slides 80) 5 outside business hours.

Display of Sequences

Sequences which have been created by the proprietor and stored in 0 the sequence database 22, in the manner described above, are displayed on the displays 20, in the following manner.

Initially, the proprietor operates the corresponding station 14 to establish communication with the server 16. This corresponds with the "log on" step 84 of Fig. 6. The process for logging on will include the station 5 identifying itself to the server 16. The server 16 consults the sequence database at 86 to identify the appropriate sequence for the station 14, which may depend on the current time of day, for example. The server identifies the first content to be displayed as part of this sequence, for example the first slide of one of the sequences as illustrated in Figs. 5a and 5b. This is step

I O 88. An instruction is then sent from the server 16 to the station 14 (step 90) to instruct the station 14 to show the slide identified at step 88. The instruction sent at 90 includes several fields, illustrated in Fig. 7a. A first field 92 identifies the station 14, for confirmation purposes. Alternatively, a hand shaking routine may be executed. A second field 94 includes sufficient

15 information to define the slide identified at step 88. This may include a complete file encoding the slide, or a slide identification by which the slide can be retrieved by further communication with the server 16 or from information held locally at the station 14, or an intermediate level of information, such as instructions for creating some of the content, and for locating and retrieving 0 the remainder of the content.

A third field 96 instructs the required duration for which the content is to be displayed.

5 On receipt of the instruction at 90, the defined slide is displayed on the display 20 for the period of time defined in field 96. This is step 98.

When the slide has been displayed, the station reports successful completion of the display at step 100 by sending a message to the server. 0 This message is illustrated in Fig. 7b. The message includes various fields, as follows. A first field 102 identifies the station 14. A second field 104 identifies the time at which the message was sent. A third field 106 identifies

the slide which has just been displayed and may also incorporate diagnostic information to confirm that the station 14 is functioning correctly. Receipt of the message at the server is first used as confirmation of successful display of the previous slide, and then as a request for the server to send a further instruction for the next slide of the sequence.

The server first assesses the report at step 108, looking particularly at fields 104 and 106. The time stamp at 104 allows the server to compare the time the message was sent, with the expected time based on the duration for which the previous slide was to be displayed (field 96 of the previous message from the server). Thus, if the report is sent sooner than expected from the instructed duration of the previous slide, or if the wrong slide is identified at 106, an anomaly is detected. Assuming that no anomalies are identified, the server determines whether or not the previous slide was drawn from the chargeable content at 26, in which case a fee is chargeable to the advertiser and a payment is due to the station proprietor. This is step 110. If necessary, the billing database is updated at step 112 to reflect the payments from the advertiser and to the proprietor, taking into account the relevant tariff identified by the tariff information in the database 24.

The processor returns to step 86 for the sequence database to be consulted to identify the next slide in the sequence.

In this way, the slides in the sequence are sequentially instructed for display by the station 14, with messages being returned between slides to confirm the display of the previous slide, and requesting details of the next slide to be displayed. Although the proprietor has had control over the creation of the sequence, the server controls the execution of the sequence and ensures, by receipt of the messages from the station, that the sequence is being executed correctly, before updating the billing information.

Other Features

Stations 14 have been described as forming a peer-to-peer network by reference to a common ISP 46, 52. In particular, station 14B includes memory 48 available to the peer-to-peer network with the station 14A, for the purposes of cache storage. Bandwidth requirements for communication between the server 16 and the stations 14 can be reduced by making use of cache memory within the peer-to-peer networks or within individual stations. For example, some elements of a slide from a sequence, such as a still or video image, may be sent from the server to the cache memory 48, when a sequence is first initiated. Thereafter, when the corresponding slide is required, the instruction (Fig. 7a) can identify the relevant content to be retrieved from the cache memory 48, but the content does not need to be transmitted between the server and the station on each occasion. The server 16 may be used to actively control the contents of the cache memory 48 so that, for example, content is deleted from the cache memory 48 when a new sequence is initiated and the content is no longer required. Consequently, the message (Fig. 7a) from the server 16 to the station 14 may include an additional field 114 containing information or instructions for the cache memory 48.

At least one of the stations 14 may be provided with an additional facility illustrated schematically at 116 as a camera in communication with the server 16 through the ISP 46. The purpose of the camera 116 is to capture images as they are displayed on a display 20 and to return those images to the server 16 for retention in the captured image database 32. This provides an additional form of feedback confirming that the display content instructed by the server has been displayed at the station 14. For example, information in the captured image database 32 may be made available to an advertiser who seeks confirmation that advertising content for which he has been charged has indeed been displayed. The provision of this feedback is

expected to be comforting to advertisers, particularly in view of the transient nature of the images being displayed.

5 The above example has described only four stations and a single advertiser. It is expected that in practice, there will be many more stations and many more advertisers. Advertisers will have a significant degree of control over the advertising by designing its content and specifying the attributes of stations which may be used for display. Furthermore, they are

I O provided with appropriate reassurance that charges are justified, because failure of the stations will result in no report or an inappropriate report being returned at step 100. The receipt of an appropriate sequence of reports at step 100 provides confirmation at the server that the chargeable content has been displayed and that the advertiser is to be charged.

15

In addition, the proprietors of the stations are also given significant control so that they can be sure that any content displayed at their station will be appropriate. Thus, they can ensure that advertisements for competing brands do not appear at their stations. Proprietors can select the content to 0 maximise income from advertisers, or to maximise promotion of their own business, or for other commercial reasons. All of these advantages are provided within a system in which the audio visual content is distributed electronically by means of a common network which can be expanded to cover very many stations and very many advertisers. Within the common 5 network, each station proprietor has control to create, accept or reject content when designing sequences, but the advertisers are nevertheless provided with adequate authentication of what, when and where the paid advertising content has been displayed. Thus, the technical arrangements which have been described allow advertisers and station proprietors sufficient control, 0 particularly by preventing station proprietors claiming advertising payments without supporting confirmation created by the operation of the system, and

without station proprietors being at risk of inappropriate content being displayed at their station.

The above description has referred to advertising content. It is to be understood that other types of content could be distributed in the same manner.

The various databases of the server have been described as discrete entities, but need not be.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.