Abstract:
A method and system for providing personal video recording functions to a client viewing a broadcast program in a multi-client network. To provide the PVR functions, predetermined storage limits are allocated for each client in a storage device on the network. Each client is permitted to execute the PVR functions if the client&#39;s stored broadcast programming has not reached the client&#39;s predetermined storage limit. Otherwise, the client is only permitted to view the broadcast program in real time or the stored broadcast program. A client may clear space in the client&#39;s allocated portion of the storage device by fast-forwarding through stored broadcast programming.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to providing video services in a Multi-Dwelling or Multi-Tenant network.  
       BACKGROUND OF THE INVENTION  
       [0002]     To support personal video recording (“PVR”) functions for all the clients in a Multi-Dwelling or Multi-Tenant (“M×U”) network one of two approaches are conventionally utilized. First, each client may be provided with a hard disk drive (“HDD”) at the client&#39;s dwelling unit. However, a major drawback is the cost incurred by the M×U network provider in providing HDDs for each dwelling unit. Second, the consumer premises equipment (“CPE”) device located at each dwelling unit may be provided access to a large storage device located at a head-end unit of the M×U network provider. Traditionally, the storage device is large enough to store all the programs ordered by the clients in the M×U network and to allow the clients use PVR functions (e.g., randomly rewinding, pause, etc . . . ) when viewing the stored programs. However, similar to the drawback encountered under the first approach the use of such a large storage device is also very expensive. The present invention is directed towards overcoming these drawbacks.  
       SUMMARY OF THE INVENTION  
       [0003]     The present invention is used in an environment where low cost network set top boxes are connected to video server. The present invention reduces the cost of the set top boxes by providing a hard drive at a Mini-Headend of the M×U network provider and eliminating the need for hard drives in the set top boxes. More particularly, a method and system for providing personal video recording functions (“PVR”) functions to a client viewing a broadcast program in a multi-client network. To provide the PVR functions, predetermined storage limits are allocated for each client in a storage device on the network. Each client is permitted to execute the PVR functions if the client&#39;s stored broadcast programming has not reached the client&#39;s predetermined storage limit. Otherwise, the client is only permitted to view the broadcast program in real time or the stored broadcast program. A client may clear space in the client&#39;s allocated portion of the storage device by fast-forwarding through stored broadcast programming.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]     In the drawings:  
         [0005]      FIG. 1  is an exemplary system diagram of the present invention;  
         [0006]      FIG. 2  is a flow chart illustrating a PVR pause process for broadcast programs of the present invention; and  
         [0007]      FIG. 3  is a block diagram illustrating an exemplary pause feature of the present invention. 
     
    
       [0008]     The characteristics and advantages of the present invention will become more apparent from the following description, given by way of example.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0009]     Referring now to  FIG. 1 , an exemplary system  10  that operates according to the principles of the present invention is shown. System  10  is an integrated digital data system to provide broadband, digital video, and services to multiple users. More specifically, system  10  integrates quality audio and video with digital IP data services for multiple users. This system design provides a platform to launch a variety of cost effective digital services. System  10  is designed to be scalable, so different digital data services can be added incrementally.  
         [0010]     System  10  includes a Mini-Headend Unit  12  where digital audio, video, and data services are received, aggregated together and distributed, and a Multi-Dwelling Unit and/or Multi-Tenant Unit (“M×U”) network  14 . Network  14  may be located in one or more apartment buildings, hotels, or any other structure where multiple clients desiring digital audio, video, and data services reside.  
         [0011]     Mini-Headend Unit  12  is responsible for receiving data, providing Quality of Service (“QoS”), providing customized services, and routing data to dwelling units  16  in the M×U network  14 . Mini-Headend unit  12  includes a Core Video Service System  18 , an Advanced Video Services System  22 , a Data Service System  24  communicatively connected to the Internet  26 , and a QoS switch  28 .  
         [0012]     Core Video Service System  18  preferably includes a Satellite Receiver System  19  communicatively connected to satellites  20 . Satellite Receiver System  19  is able to scale the number of streams received from satellites  20  in accordance with the number of clients desiring service. More specifically, Satellite Receiver system  18  runs a multi-cast server to allow network set top boxes  44  in the dwelling units  16  to request digital data streams. Satellite Receiver system  18  scales by the number of tuning blades in the chassis until all transponders for the satellite are being received. A fully-loaded chassis having  60  transponders is able to handle an input data rate of 2.4 Gbps. At this point, the chassis is able to handle n users by accepting a new user request to the appropriate multi-cast group. Satellite Receiver System  19  is able to receive satellite signals and output IP packets at a data rate of 2 Gbps to multi-cast aware switch  28 . More specifically, The IP packets that are sent out use QoS (as set forth in standards IEEE 802.1p (entitled “Traffic Class Expediting and Dynamic Multicast Filtering”) and IEEE 802.1q (entitled “Virtual LANs”)) to insure that the packets are delivered promptly. The network interface on the Satellite Receiver System  19  is a 1 Gbps Ethernet port and is expandable to two 1 Gbps Ethernet ports. A management system of the Satellite Receiver  19  accepts requests for programs from clients. The management system allows clients to select a satellite, transponder, and program IDs, and allows the Satellite Receiver System  19  to provide specific program streams to the client. The management system also supports multi-casting to save bandwidth. Although satellite receiver system  19  and satellites  20  are illustrated as the content delivery medium in  FIG. 1 , the use of other media (e.g., cable, fiber, etc.) for delivering content is considered within the scope of the invention.  
         [0013]     Advanced Video Services system  22  is a platform that works in conjunction with the Satellite Receiver  19  to enable additional digital video services. Advance Video Services system  22  is scaled according to the number of clients using the service. For example, system  22  may require more servers  30  as the number of clients increases. The types of services provided are, inter alia, Video On Demand, Near Video On Demand, Limited Video On Demand, Nielsen Ratings, Time Shift, Auto Record, Personal Video Recording (“PVR”), and the like. Advanced Video System  22  includes a Conditional Access System (not shown) that is used for program streams that are recorded to hard drive(s)  32 . When recording, the original program stream received from Satellite Receiver System  19  is decrypted, picture data is extracted, and a new program stream (containing the extracted picture data) is encrypted and stored onto hard drive(s)  32 . The network provider&#39;s conditional access system is terminated at the Advanced Video System Server  30  and the new conditional access system is used thereafter.  
         [0014]     Data Service System  24  is scaled according to the number of clients using internet service and the required speed or bandwidth of the internet service.  
         [0015]     Mini-Headend unit  12  may include a Gigabit QoS Ethernet switch  28  (necessary for medium to large systems) that is scalable and can be removed in small installations. As known by those skilled in the art, some of the issues that are considered when selecting switch  28  are the type of services provided and how many dwelling units  16  in M×U network  14  need to be supported. Switch  28  provides connectivity between Satellite Receiver System  19 , Advance Video Services system  22  and Data Services System  24 . Switch  28  also provides connectivity from the Mini-Headend unit  12  to the M×U network  14 . Switch  28  supports full-duplex Gigabit Ethernet interfaces and is scalable to support systems of various sizes. Switch  28  supports the QoS set forth in the IEEE 802.1p and 802.1q standards. Having QoS facilitates the communication between switch  28  and Advanced Video Services System  22  and Data Services System  24 . More specifically, video data from Video Services system  18  and Advanced Video Services system  22  is given a higher priority than data from Data Service system  24 . For example, when video data and internet data is simultaneously requested, video data is transmitted first and the internet data is either transmitted simultaneously if enough bandwidth is available or transmitted at a later time when sufficient bandwidth becomes available.  
         [0016]     M×U network  14  includes a service rack  34  and dwelling units  16 . Service rack  34  is scalable according to the number of dwelling units  16  in the M×U network  14  and is located in the central point where the phone lines in the M×U network  14  come together. The number of M×U networks  14  in system  10  dictates the number of service racks  34  required. Preferably, a service rack  34  is provided for each network  14  (e.g., building) in a multi-network environment (e.g., a multiple building complex). Each service rack  34  includes a VDSL switch  36  that uses a Plain Old Telephone Service (“POTS”) Splitter  38  to combine POTS service  40  with the digital video, audio, and data received from the QoS switch  28  of Mini-Headend  12  via a 1 Gbps phone line. Although VDSL switch  36  is illustrated as being an Ethernet QAM switch, it should be noted that the use of any other Ethernet switch is considered within the scope of the present invention.  
         [0017]     In system  10  each Dwelling Unit  16  that has subscribed to digital services is required to have a consumer premises equipment (“CPE”) device. The CPE device for a given dwelling unit  16 , depending on the client&#39;s service subscription, may include a modem  42 , a network set top box (“STB”)  44 , both a modem  42  and a STB  44 , or an integrated modem and STB unit (not shown). The exemplary system  10  of the present invention requires at least the modem  42  for the reception of digital data, audio, and video services. Modem  42  is connectable to switch  36  via phone lines and terminates the VDSL line. Modem  42  also has a POTS Splitter (not shown) and a connection for phone services  46 . Modem  42  has an Ethernet port to provide computers  48  internet access and network STBs  44  access to audio and video services.  
         [0018]     Although phone lines are shown as being used as the communication medium between the dwelling units  16  and the Mini-Headend unit  12 , cable and wireless networks are considered within the scope of the invention.  
         [0019]     In summary, system  10  provides the architecture to deliver, inter alia, digital audio, digital video, high-speed Internet access, telephony services, security services, and the like to a client residing at a dwelling unit  16 , and provides a revenue stream and a platform to add incremental or new services to the system provider.  
         [0020]     Referring now to  FIG. 2 , a personal video recording (“PVR”) memory management process  50  of the present invention is shown. After a client, at step  52 , requests, via STB  44 , the display of a broadcast program (e.g., a program received from Core Video Service system  18 ), Mini-Headend unit  12  instructs the Satellite Receiver system  19  to deliver the requested program to the requesting STB  44  via switches  28  and  36 . Upon receipt of the program, STB  44 , at step  54 , displays the program to the client. During the viewing of the program the client may, at step  56 , attempt to pause the program. Upon receipt of a pause request from STB  44 , Mini-Headend unit  12 , at step  58 , determines whether the client&#39;s parameter limit has been reached. The parameter limit represents the amount of storage space allocated to the client on hard drives  32 . VOD server  30  allocates the amount of storage for each client. It should be noted that each client may receive the same amount of storage space or different clients may receive different amounts of storage space. For example, the amount of storage space allocated may be based on the type of subscription a client has or a fee paid by a client. If so, the Mini-Headend unit denies the pause request and STB  44  returns to step  54  and continues to display the program. If not, Mini-Headend unit  12  instructs switch  28  to route the program to the VOD server  30  and instructs VOD server  30 , at step  60 , to store the program on a storage device (e.g., hard drive  32 ). Mini-Headend unit  12  then, at step  62 , monitors the client&#39;s parameter limit and, if the limit is not reached, continues to pause the display of the program to the client and store the program in the storage device. However, if the parameter limit is exceeded Mini-Headend unit  12 , at step  64 , instructs VOD server  30  to deliver the stored program to the client and to continue storing the broadcast program in the hard drive by writing over the portion of the stored program that has been delivered to the client. Mini-Headend unit  12  simultaneously instructs the STB  44  to resume the display of the program.  
         [0021]     Referring now to  FIG. 3 , an illustration of a PVR pause/rewind storage management process  70  wherein two clients are viewing the same program stream is shown. At block  72 , clients  1  and  2  request the same program stream. At block  74 , as both clients are viewing the stream, client  1  pauses its view. Client  2  is still receiving the program stream. Since client  1  paused the stream, the receiver system is sending the data to a storage device (as shown by the change in the program storage allocation for client  1 . At bock  76 , client  2  decides to pause and client  1  resumes viewing. Both clients are viewing the program stream in their own time domain (i.e., client  1  is viewing a stored portion of the program stream and client  2  was, until the pause, viewing the program stream in real time). For various reasons storage pace on hard drives  32  may be at a premium. When this is the case, Mini-Headend unit  12  sets a parameter indicating how much storage per client to allocate for a paused program stream. At block  78 , client  2  has remained paused. As the stored program hits the parameter limit, the pause feature is disabled for client  2 , and client  2  is forced to view the stored program in a broadcast model (i.e., no pause or rewind permitted). client  1 , who has been viewing the program during this period, can still pause rewind the program. Both clients can fast forward through the stored program and join in viewing the original broadcast. If client  2  does so, the pause feature will be re-enabled for client  2 .  
         [0022]     Although the present invention has been described in conjunction with the embodiments disclosed herein, it should be understood that the foregoing description is intended to illustrate and not limit the scope of the invention as defined by the claims.