Patent Publication Number: US-2009228941-A1

Title: Video System and a Method of Using the Video System

Description:
FIELD OF THE DISCLOSURE 
     The present disclosure relates to video systems and methods of using the video systems. 
     BACKGROUND 
     Digital networks can be used to transmit voice communications, video content, and data (other than voice or video). The digital networks may be managed and controlled to provide at least a minimum bandwidth and data integrity of the information transmitted over the digital network. Dropped packets are typically not a problem for browser applications, as the dropped packets can be retransmitted without a significant adverse impact. For voice communications, the dropped packet may be assumed to be silence or a bad connection. For video content such as a video clip or a movie, a substantial portion of the content may be buffered or otherwise saved prior to its display. Dropped packets from the video content can be retransmitted before a frame with the dropped packet would be seen by an end user. For data, retransmitting dropped packets during a download is typically not problematic. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Skilled artisans will appreciate that for simplicity and clarity of illustration, elements illustrated in the Figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements are exaggerated relative to other elements. Embodiments incorporating teachings of the present disclosure are shown and described with respect to the drawings presented herein, in which: 
         FIG. 1  includes a block diagram illustrating an embodiment of an Internet protocol television system; 
         FIG. 2  includes a block diagram illustrating some of the connections between the customer premises and other portions of a network that supports the Internet protocol television system; 
         FIG. 3  includes an architecture that can be used to test a video system; 
         FIG. 4  includes an architecture that can be used with groupings of capture devices with associated measurement systems; 
         FIG. 5  includes a flow diagram illustrating a method of testing transmission of a test video clip over a dedicated test channel of a service provider&#39;s access network; and 
         FIG. 6  includes a block diagram of an illustrative embodiment of a general computer system. 
     
    
    
     The use of the same reference symbols in different drawings indicates similar or identical items. 
     DETAILED DESCRIPTION OF THE DRAWINGS 
     The numerous innovative teachings of the present application will be described with particular reference to the presently preferred exemplary embodiments. However, understand that this class of embodiments provides only a few examples of the many advantageous uses of the innovative teachings herein. In general, statements made in the specification of the present application do not necessarily delimit any of the various claimed inventions. Moreover, some statements may apply to some inventive features but not to others. 
       FIG. 1  includes an illustration of an Internet protocol television (“IPTV”) system  100  including a client facing tier  102 , an application tier  104 , an acquisition tier  106 , and an operations and management tier  108 . Each tier  102 ,  104 ,  106 , and  108  is coupled to one or both of a private network  110  and a public network  112 . For example, the client-facing tier  102  can be coupled to the private network  110 , while the application tier  104  can be coupled to the private network  110  and to a public network, such as the Internet. The acquisition tier  106  can also be coupled to the private network  110  and to the public network  112 . Moreover, the operations and management tier  108  can be coupled to the public network  112 . 
     The various tiers  102 ,  104 ,  106  and  108  communicate with each other via the private network  110  and the public network  112 . For instance, the client-facing tier  102  can communicate with the application tier  104  and the acquisition tier  106  via the private network  110 . The application tier  104  can also communicate with the acquisition tier  106  via the private network  110 . Further, the application tier  104  can communicate with the acquisition tier  106  and the operations and management tier  108  via the public network  112 . Moreover, the acquisition tier  106  can communicate with the operations and management tier  108  via the public network  112 . In a particular embodiment, elements of the application tier  104  can communicate directly with the client-facing tier  102 . 
     The client-facing tier  102  can communicate with user equipment via a private access network  166 , such as an IPTV network. In an illustrative embodiment, modems, such as a first modem  114  and a second modem  122 , can be coupled to the private access network  166 . The client-facing tier  102  can communicate with a first representative set-top box (“STB”) device  116  via the first modem  114  and with a second representative STB device  124  via the second modem  122 . The client-facing tier  102  can communicate with a large number of STBs over a wide geographic area, such as a regional area, a metropolitan area, a viewing area, or any other suitable geographic area that can be supported by networking the client-facing tier  102  to numerous STB devices. In one embodiment, the client-facing tier  102  can be coupled to the modems  114  and  122  via fiber optic cables. Alternatively, the modems  114  and  122  can be digital subscriber line (“DSL”) modems that are coupled to one or more network nodes via twisted pairs, and the client-facing tier  102  can be coupled to the network nodes via fiber-optic cables. Each STB device  116  and  124  can process data received from the private access network  166  via an IPTV software platform, such as Microsoft® TV IPTV Edition. 
     The first STB device  116  can be coupled to a first display device  118 , such as a first television monitor, and the second STB device  124  can be coupled to a second display device  126 , such as a second television monitor. Moreover, the first STB device  116  can communicate with a first remote control  120 , and the second STB device can communicate with a second remote control  128 . In an exemplary, non-limiting embodiment, each STB device  116  and  124  can receive data or video from the client-facing tier  102  via the private access network  166  and render or display the data or video at the display device  118  or  126  to which it is coupled. The STB devices  116  and  124  thus may include tuners that receive and decode television programming information for transmission to the display devices  118  and  126 . Further, the STB devices  116  and  124  can include an STB processor  170  and an STB memory device  172  that is accessible to the STB processor. In a particular embodiment, the STB devices  116  and  124  can also communicate commands received from the remote controls  120  and  128  back to the client-facing tier  102  via the private access network  166 . 
     In an illustrative embodiment, the client-facing tier  102  can include a client-facing tier (“CFT”) switch  130  that manages communication between the client-facing tier  102  and the private access network  166  and between the client-facing tier  102  and the private network  110 . As shown, the CFT switch  130  is coupled to one or more data servers  132  that store data transmitted in response to user requests, such as video-on-demand (“VOD”) content. The CFT switch  130  can also be coupled to a terminal server  134  that provides terminal devices, such as a game application server and other devices with a common connection point to the private network  110 . In a particular embodiment, the CFT switch  130  can also be coupled to a VOD server  136 . 
     The application tier  104  can communicate with both the private network  110  and the public network  112 . In this embodiment, the application tier  104  can include a first application tier (“APP”) switch  138  and a second APP switch  140 . In a particular embodiment, the first APP switch  138  can be coupled to the second APP switch  140 . The first APP switch  138  can be coupled to an application server  142  and to an OSS/BSS gateway  144 . The application server  142  provides applications to the STB devices  116  and  124  via the private access network  166 , so the STB devices  116  and  124  can provide functions, such as display, messaging, processing of IPTV data and VOD material. In a particular embodiment, the OSS/BSS gateway  144  includes operation systems and support (“OSS”) data, as well as billing systems and support (“BSS”) data. 
     The second APP switch  140  can be coupled to a domain controller  146  that provides web access, for example, to users via the public network  112 . The second APP switch  140  can be coupled to a subscriber and system store  148  that includes account information, such as account information that is associated with users who access the system  100  via the private network  110  or the public network  112 . In a particular embodiment, the application tier  104  can also include a client gateway  150  that communicates data directly to the client-facing tier  102 . In this embodiment, the client gateway  150  can be coupled directly to the CFT switch  130 . The client gateway  150  can provide user access to the private network  110  and the tiers coupled thereto. 
     In a particular embodiment, the STB devices  116  and  124  can access the system via the private access network  166  using information received from the client gateway  150 . The private access network  166  provides security for the private network  110 . User devices can access the client gateway  150  via the private access network  166 , and the client gateway  150  can allow such devices to access the private network  110  once the devices are authenticated or verified. Similarly, the client gateway  150  can prevent unauthorized devices, such as hacker computers or stolen STB devices, from accessing the private network  110 , by denying access to these devices beyond the private access network  166 . 
     For example, when the STB device  116  accesses the system  100  via the private access network  166 , the client gateway  150  can verify subscriber information by communicating with the subscriber and system store  148  via the private network  110 , the first APP switch  138  and the second APP switch  140 . Further, the client gateway  150  can verify billing information and status by communicating with the OSS/BSS gateway  144  via the private network  110  and the first APP switch  138 . The OSS/BSS gateway  144  can transmit a query across the first APP switch  138 , to the second APP switch  140 , and the second APP switch  140  can communicate the query across the public network  112  to the OSS/BSS server  164 . After the client gateway  150  confirms subscriber and/or billing information, the client gateway  150  can allow the STB device  116  access to IPTV content and VOD content. If the client gateway  150  cannot verify subscriber information for the STB device  116 , such as because it is connected to a different twisted pair, the client gateway  150  can deny transmissions to and from the STB device  116  beyond the private access network  166 . 
     The acquisition tier  106  includes an acquisition tier (“AQT”) switch  152  that communicates with the private network  110 . The AQT switch  152  can also communicate with the operations and management tier  108  via the public network  112 . In a particular embodiment, the AQT switch  152  can be coupled to a live acquisition server  154  that receives television content, for example, from a broadcast service  156 . Further, the AQT switch  152  can be coupled to a VOD importer server  158  that stores television content received at the acquisition tier  106  and communicate the stored content to the client-facing tier  102  via the private network  110 . 
     The operations and management tier  108  can include an operations and management tier (“OMT”) switch  160  that conducts communication between the operations and management tier  108  and the public network  112 . In the illustrated embodiment, the OMT switch  160  is coupled to a TV 2  server  162 . Additionally, the OMT switch  160  can be coupled to an OSS/BSS server  164  and to a simple network management protocol (“SNMP”) monitor  163  that monitors network devices. In a particular embodiment, the OMT switch  160  can communicate with the AQT switch  152  via the public network  112 . 
     In a particular embodiment, during operation of the IPTV system, the live acquisition server  154  can acquire television content from the broadcast service  156 . The live acquisition server  154  in turn can transmit the television content to the AQT switch  152 , and the AQT switch  152  can transmit the television content to the CFT switch  130  via the private network  110 . Further, the television content can be encoded at the D-servers  132 , and the CFT switch  130  can communicate the television content to the modems  114  and  122  via the private access network  166 . The STB devices  116  and  124  can receive the television content from the modems  114  and  122 , decode the television content, and transmit the content to the display devices  118  and  126  according to commands from the remote control devices  120  and  128 . 
     Additionally, at the acquisition tier  106 , the VOD importer server  158  can receive content from one or more VOD sources outside the IPTV system  100 , such as movie studios and programmers of non-live content. The VOD importer server  158  can transmit the VOD content to the AQT switch  152 , and the AQT switch  152  in turn can communicate the material to the CFT switch  130  via the private network  110 . The VOD content can be stored at one or more servers, such as the VOD server  136 . 
     When a user issues a request for VOD content to the STB device  116  or  124 , the request can be transmitted over the private access network  166  to the VOD server  136  via the CFT switch  130 . Upon receiving such a request, the VOD server  136  can retrieve requested VOD content and transmit the content to the STB device  116  or  124  across the private access network  166  via the CFT switch  130 . In an illustrative embodiment, the live acquisition server  154  can transmit the television content to the AQT switch  152 , and the AQT switch  152  in turn can transmit the television content to the OMT switch  160  via the public network  112 . In this embodiment, the OMT switch  160  can transmit the television content to the TV 2  server  162  for display to users accessing the user interface at the TV 2  server. For example, a user can access the TV 2  server  162  using a personal computer (“PC”)  168  coupled to the public network  112 . 
     The domain controller  146  communicates with the public network  112  via the second APP switch  140 . Additionally, the domain controller  146  can communicate via the public network  112  with the PC  168 . For example, the domain controller  146  can display a web portal via the public network  112  and allow users to access the web portal using the PC  168 . Further, in an illustrative embodiment, the domain controller  146  can communicate with at least one wireless network access point  178  over a data network  176 . In this embodiment, each wireless network access device  178  can communicate with user wireless devices, such as a cellular telephone  180 . 
     In a particular embodiment, the STB devices can include an STB computer program  174  that is embedded within the STB memory device  172 . The STB computer program  174  can contain instructions to receive and execute at least one user television viewing preference that a user has entered by accessing an Internet user account via the domain controller  146 . For example, the user can use the PC  168  to access a web portal maintained by the domain controller  146  via the Internet. The domain controller  146  can query the subscriber and system store  148  via the private network  110  for account information associated with the user. In a particular embodiment, the account information can associate the user&#39;s Internet account with the second STB device  124 . For instance, in an illustrative embodiment, the account information can relate the user&#39;s account to the second STB device  124  by associating the user account with an IP address of the second STB device  124 , with data relating to one or more twisted pairs connected with the second STB device  124 , with data related to one or more fiber optic cables connected with the second STB device  124 , with an alphanumeric identifier of the second STB device  124 , with any other data that is suitable for associating second STB device  124  with a user account, or with any combination of these. 
       FIG. 2  includes an illustration of a portion of an exemplary network  200  that can be used to deliver digital content, such as IPTV using the IPTV system  100  in  FIG. 1 , to a customer. The network can include a super hub office (“SHO”)  220  that is bidirectionally coupled to an Internet protocol backbone (“BB”)  222  that is bidirectionally coupled to each of the Internet  224  and a video hub office (“VHO”)  226 . In one embodiment, streaming video content provided from a national broadcaster (e.g., ABC™, CBS™, CNN™, HBO™, etc.) can be sent to and received by the SHO  220 . Streaming video content from local broadcasters can be sent to and received by the VHO  226 . VOD content can be received by and stored within the VHO  226 . Internet access can be established via the BB  222  to the Internet  224 . Such Internet access can be useful for obtaining files, making calls, requesting other content, or any combination thereof by a customer at the customer premises. 
     Continuing with the network  200 , an intermediate office (“IO”)  242  is bi-directionally coupled to the VHO  226  and a central office (“CO”)  244 . The CO  244  is bidirectionally coupled to a video access device (“VAD”)  262 . The VAD  262  can be a digital subscriber line access multiplexer, a video ready access device, or the like. The video access ready device is similar to the digital subscriber line access multiplexer, but the video access ready device is particularly designed for streaming broadcast video for IPTV. The VAD  262  is bidirectionally coupled to customer premises equipment (“CPE”)  282 . 
     After reading this specification, skilled artisans will appreciate that many different network configurations are possible. For example, VOD content may be accessed by a customer via the Internet  224  or the SHO  220 , instead of the VHO  226 . No intermediate office or a plurality of intermediate offices similar to the IO  242  may be used. More than one SHO or VHO may also be used. Thus, the particular implementation of a network used to provide services to a customer is variable and can be tailored to the needs or desires of a network operator. Therefore, the network  200  in  FIG. 2  is merely for purposes of illustration and is not to be construed as limiting the scope of the present invention. 
       FIG. 3  includes an illustration of an architecture that can be used to automatically test a packet-switched network of a service provider, wherein the packet-switched network is operable to stream packets of video broadcasts in real time or near real time. An IPTV network is an example of such a network. In  FIG. 3 , an exemplary testing system  300  can be used to inject packets corresponding to one or more test video clips into the network to simulate a broadcast transmission, however, the test video clips can be broadcast over a dedicated test channel, rather than an entertainment broadcast channel. As used herein, an entertainment broadcast channel is a channel of the network over which end users, such as customers of the service provider, receive video content for their own use and enjoyment. The entertainment broadcast channels can correspond to the national or local broadcasters. The dedicated test channel is a channel of the network over which test packetized data streams corresponding to test video clips or other test video content are principally transmitted. In a particular embodiment, the dedicated test channel only transmits test packetized data streams and test video content, and in a more particular embodiment, test packetized data streams are normally transmitted at substantially all times. The dedicated test channel may not be operational during abnormal times, such as a power outage, service or maintenance, or another event. 
     The test video clip can be in a Motion Pictures Expert Group (“MPEG”) standard, such as MPEG-2, MPEG-4, or another digital format. In a particular embodiment, test video clip can include I-Frames, P-Frames, and B-Frames. Referring briefly to  FIG. 3 , the test video clip can be stored at or accessible to the test controller  402 , the source system  422  or  424 , the measurement system  442 ,  444 ,  446 , or  448 , or any combination thereof. When transmitted, the source system  422  or  424  or network equipment at the SHO  220  or VHO  226  can convert the test video clip into a test packetized data stream for transmission over the service provider&#39;s access network, such as the private access network  116  as illustrated in  FIG. 1 . The test packetized data stream can be transmitted over the dedicated test channel at a regular or other interval. The test video clip can simulate conditions that could occur, such as using all possible colors, text, audio, high-speed motion, slow-speed motion, fading, changing from motion to still pictures, synchronization, another suitable condition, or any combination thereof. 
     The system  300  includes a test controller  402  that is bidirectionally coupled to a network  412 . The test controller  402  can be operated to create topology information, such as source and measurement systems, which are described in more detail later in this specification. The test controller  402  can also be operable to establish and maintain connectivity to the source and measurement systems, set broadcast schedules to be used by the source systems, set polling intervals on the measurement systems at regular intervals (e.g., once a day) for measurement data, and poll any measurement system for status and measurement results, correlate the measurement data for providing reports, generate proactive real-time reports, generate predictive reports such as a fault trend report, detect progressive degradation of service/location automatically, provide other information regarding alarms, alerts, or status, or any combination thereof. The test controller  402  can be in the form of a computer system, such as a server. 
     In an embodiment, the network  412  can be a public network or a private network, such as private network  110  as illustrated in  FIG. 1 . The network  412  is bidirectionally coupled to a source system  422 . The source system  422  can be accessed and controlled by the test controller  402 . The source system  422  can be operable to act as the source for the test video clip, maintain connectivity to broadcast network equipment in the SHO  220 , send the test video clip to the SHO  220 , provide another suitable function, associate the test video clip with the dedicated test channel, or any combination thereof. The source system  422  can be in the form of a computer system, such as a server. 
     As illustrated in the embodiment in  FIG. 3 , the source system  422  is bidirectionally coupled to the SHO  220 . More particularly, the source system  422  can be bidirectionally coupled to broadcast network equipment, such as transmission equipment (e.g., a router). The test video clip may be converted to a test packetized data stream by the source system  422  or network equipment at the SHO  220 . The network equipment can transmit the test video clip as a test packetized data stream along a broadcast transmission path  482  over the dedicated test channel, wherein the broadcast transmission path  482  can also be used to transmit other packets of other packetized data streams over the entertainment broadcast channels. Thus, a data stream may or may not be a continuous uninterrupted series of packets. In a particular embodiment, packets that are part of the test video clip can be interleaved with packets for entertainment broadcast channels. At the source system  422 , the packets can be associated with an identifier corresponding to the dedicated test channel. For example, an identifier within a header or other part of the packet can be assigned a value corresponding to the dedicated test channel. 
     In a particular embodiment, the test system  420  can be used to control when the source system  422  is to provide the test video clips or test packetized data streams to the SHO  220  for transmission over the dedicated test channel. For example, the test packetized data streams corresponding to the test video clips may be transmitted over the dedicated test channel at substantially all times. In another embodiment, any particular test packetized data streams may be transmitted at a regularly scheduled interval or may be transmitted on an ad-hoc or other irregular basis. After reading this specification, skilled artisans will be able to determine how frequently particular test packetized data streams are to be transmitted over the dedicated test channel. 
     In another embodiment, another source system  424  can be used. The other source system  424  can be bidirectionally coupled to the network  412 . The other source system  424  may perform any of the functions and include the features as described with respect to the source system  422 . As illustrated in the embodiment in  FIG. 3 , the other source system  424  can be operable to act as the source for the test video clip or test packetized data streams, maintain connectivity to broadcast network equipment in the VHO  226 , send the test video clip as to the VHO  226 , provide another suitable function, associate the test video clip with the dedicated test channel, or any combination thereof. The other source system  424  can be in the form of a computer system, such as a server. 
     In  FIG. 3 , the source system  424  is bidirectionally coupled to the VHO  220 . More particularly, the other source system  424  can be bidirectionally coupled to broadcast network equipment, such as transmission equipment (e.g., a router). The broadcast network equipment can transmit the test video clip as a test packetized data stream along a broadcast transmission path  484  over the dedicated test channel, wherein the broadcast transmission path  484  can also be used to transmit other packets of other packetized data streams over the entertainment broadcast channels. 
     The source system  422  can be used in a manner to simulate transmissions that video content from the national broadcasters would be transmitted using the service provider&#39;s access network, and the other source system  424  can be used in a manner to simulate transmissions that video content from the local broadcasters would be transmitted using the service provider&#39;s access network. The broadcast transmission path  482  can be the longest normal broadcast transmission path within the service provider&#39;s access network to the CPE  282 , and the broadcast transmission path  484  can be an intermediate broadcast transmission path within the service provider&#39;s access network to the CPE  282 . In still another embodiment, another source system (not illustrated) can be used and be coupled to a point between the VHO  226  and the CPE  282 . In yet another embodiment, the source system  422  may be coupled to the VHO  226 , IO  242 , the CO  244 , or the VAD  262  in place of or in addition to being coupled to the SHO  226 . Thus, the other source system  424  is not needed but can be used if desired. 
     When the source system  422  is coupled to the SHO  220 , the test packetized data stream corresponding to the test clip is transmitted from the SHO  220 . The network equipment at VHO  226  and other points downstream (going towards CPE  282 ) can transmit, route, or perform other functions such that the test packetized data stream is received by the measurement systems  442 ,  444 , or  446  or the capture device  462 , as illustrated in  FIG. 3 . The measurement system  442  is bidirectionally coupled to the network  412  and the VHO  226 , the measurement system  444  is bidirectionally coupled to the network  412  and the IO  242 , and the measurement system  446  is bidirectionally coupled to the network  412  and the CO  244 . The capture device  462  is bidirectionally coupled to the VAD  262  and a measurement system  448 , which is bidirectionally coupled to the network  412 . 
     Each of the measurement systems  442 ,  444 ,  446 , and  448  can be accessed and controlled by the test controller  402 . Each of the measurement systems  442 ,  444 ,  446 , and  448  can be operable to act as a measurement collector and data aggregator for the dedicated test channel, receive and test packetized data streams that have been broadcast over the dedicated test channel at its particular point along the broadcast transmission path, performing another suitable function, or any combination thereof. Each of the measurement systems  442 ,  444 ,  446 , and  448  can be in the form of a computer system, such as a server. 
     In a particular embodiment, a router or other similar network equipment along the broadcast transmission path can parse packets within the test packetized data stream and determine that such packets are being transmitted over the dedicated test channel. The router will transmit the packets downstream, and if a measurement system or capture device is coupled to the router, the router will also transmit the packets to the measurement system or capture device. 
     At the measurement systems  442 ,  444 ,  446 , and  448 , one or more tests can be performed. In an embodiment, after receiving packets for the test packetized data stream, the measurement system can generate the test video clip from the packets. The measurement system can compare the received test video clip to a previously stored test video clip in the measurement system. In a particular embodiment, the test controller  402  can transmit the test video clip to the measurement system via the network  412 , and the test video clip from the test controller  402  can be used instead of the stored test video clip. The test controller  402  can provide specification, control or other limits to the measurement systems to be used in conjunction with the tests. The limits can be for alarms, alerts, or any combination thereof. The measurement systems can automatically generate and send a notice regarding an alarm or alert to a trouble ticketing system or other similar system when a test result is beyond a limit. The measurement system can also be polled at predetermined or other intervals by the test controller  402  to collect measured parameters or other test results. 
     The measurement system may be operable to perform other functions. In another embodiment, tests may be performed on the test packetized data stream or test video clip to determine changes that may or may not be a function of time. For example, a particular test video clip can be transmitted as a packetized data stream on a reoccurring basis (e.g., hourly, daily, etc.). A difference in any parameter, whether it is the test video clip itself or data collected as the test packetized data steam was being broadcast or received (e.g., transmission rate, dropped packets, etc.) between any two transmissions, can be determined. The difference can be expressed as a magnitude (e.g., an absolute value), a magnitude and sign (e.g., + or −), or as a relative value (e.g., percentage change) with or without a sign. In this manner, the service provider may gain information if a portion of the service provider&#39;s access network is trending in a direction before an alarm or alert is reached. In still another embodiment, more than one difference can be collected, and changes between the differences (similar to a second derivative) can be obtained. In still a further embodiment, readings can be integrated over time. Thus, a service provider can develop relatively simple or complex schemes (e.g., proportional, derivative, or integral control) for monitoring and potentially controlling a broadcast portion of the service provider&#39;s access network. 
     The capture device  462  can be operable to capture the test packetized data stream or other test video content received over the dedicated test channel and send the captured test packetized data stream or other test video content to a corresponding measurement system, such as the measurement system  448 . The capture device  462  can be relatively inexpensive, small, environmentally insensitive, or any combination thereof. In a particular embodiment, each VAD  262  will have a corresponding capture device  462 . The VAD  262  and corresponding capture device  462  can be co-located within the same housing, where the housing is exposed to an outdoor ambient. Thus, more sensitive measuring equipment, such as the measurement system  448 , can be located within a structure, such as an office, remote to the housing and maintained similar to office computer systems. 
     Many other configurations can be used and not depart from the concepts as described herein. As illustrated in  FIG. 3 , the source system  422  can be coupled to network equipment at more than one SHO  220 , the other source system  424  can be coupled to network equipment at more than one VHO  226 , or any combination thereof. Similarly, the measurement system  442  can be coupled to network equipment at more than one VHO  226 , the measurement system  444  can be coupled to network equipment at more than one IO  242 , the measurement system  446  can be coupled to network equipment at more than one CO  244 , or any combination thereof. 
     In another embodiment, a clustered configuration can be used for capture devices and measurement systems, as illustrated in  FIG. 4 . The network  412  can be bidirectionally coupled to measurement systems  4482 ,  4484 ,  4486 , and  4488 . The measurement systems  4482 ,  4484 ,  4486 , and  4488  can be bidirectionally coupled to sets of capture devices  4622 ,  4624 ,  4626 , and  4628 , respectively, and the sets of capture devices  4622 ,  4624 ,  4626 , and  4628  can be bidirectionally coupled to sets of VADs  2622 ,  2624 ,  2626 , and  2628 , respectively. The measurement systems  4482 ,  4484 ,  4486 , and  4488 , sets of capture devices  4622 ,  4624 ,  4626 , and  4628 , and the sets of VADs  2622 ,  2624 ,  2626 , and  2628  can perform the functions as previously described with respect to the measurement systems  448 , the capture device  462 , and the VAD  262 . 
     In a particular embodiment, each capture device within the sets of capture devices is coupled to a single VAD within the sets of VADs, and a plurality of capture devices are coupled to a single measurement system. The test controller  402  controls the measurement systems  4482 ,  4484 ,  4486 , and  4488 , and the measurement systems  4482 ,  4484 ,  4486 , and  4488  control their corresponding capture devices. 
     In still another embodiment (not illustrated), a capture device may be coupled to a measurement system and network equipment at an office along a broadcast transmission path. For example, a capture device may be coupled to the measurement system  446  and network equipment within the CO  244 . 
     More or fewer source or measurement systems may be used. For example, each office may have its own source system, similar to source system  422 . Thus, a source system may be coupled to network equipment at the IO  242  or the CO  244 . In another embodiment, a single source system may be used for the service provider&#39;s access network. The single source system may be configured such that it is operable to inject a test packetized data stream at nearly any point along a broadcast transmission path. In still another embodiment, the same measurement system may be used for the VHO  224  and the IO  242 . In a further embodiment, more than one measurement system can be used for the CO  244 . In still a further embodiment, a capture device, a measurement system, or both may be temporarily or permanently coupled to the CPE  282 . For example, the capture device or measurement system may be connected to a network interface device at the customer premises when performing a service call, to receive video content as broadcasted over the dedicated test channel at the customer premises. 
     The source and measurement systems can be located at their corresponding offices at which such systems connect to the network equipment. For example, the source system  422  can be at the same site as the SHO  220 , and the measurement system  442  can be at the same site as the VHO  226 . In another embodiment, any of the source and measurement systems may be located at the same site as the test controller  402 . Measurement systems for different parts of the broadcast network may be located at the same site. For example, a measurement system for a particular CO  244  and a measurement system for VADs  262  served by that particular CO  244  may be located at the particular CO  244 . 
     After reading this specification, skilled artisans will appreciate that many other configurations and location strategies may be used to service the needs or desires for their particular application. The test system  400  can be separate from and used to provide information to a management system used to manage the service provider&#39;s access network. In a particular embodiment, each of the test controller  402 , the source systems  422  and  424 , the measurement systems  442 ,  444 ,  446 , and  448 , and the capture device  462  (collectively, the “Test Equipment”) are located outside the broadcast transmission path. Video or other content that is provided to the CPE  282  does not pass through the Test Equipment. Thus, the Test Equipment can be added, removed, modified, be in use, not be in use, or any combination thereof without any significant affect on the CPE  282 . Other than viewing the dedicated test channel, a customer using the CPE  282  may not realize that the Test Equipment is or is not present or whether the Test Equipment is or is not operational. Therefore, the customer can enjoy video content received over one or more entertainment broadcast channels, while the Test Equipment is ensuring a relatively high level of quality of experience by the customer. 
     In another embodiment, the test system  400  or a portion thereof (e.g., the test controller  402 ) may be part of the management system. Broadcast data streams, including the test packetized data streams using the dedicated test channel, do not pass through the capture devices or the measurement systems on the way to the CPE  282 . Thus, the test system  400  can be used without significantly interfering with reception of video content over entertainment broadcast channels or the dedicated test channel at the CPE  282 . 
     The test packetized data streams can be pushed to or pulled by Test Equipment. In an embodiment, the capture device  462  may push a test packetized data stream to the measurement system  448  without any corresponding action by the measurement system  448 . In another embodiment, the capture device  462  may transmit a test packetized data stream to the measurement system  448  only after the capture device  462  receives a request, is polled, or is acted upon by the measurement system  448 . Similarly, the information generated by the measurement systems  442 ,  444 ,  446 , and  448  may be pushed to or pulled by the test controller  402 . After reading this specification, skilled artisans will be able to design a test system that meets the needs or desires, given a particular application. 
       FIG. 5  includes a flow diagram of a method of using the test system. In one embodiment, all operations described with respect to  FIG. 5  may be performed by a measurement system. In another embodiment, an operation or a portion of an operation may be performed by a different device within the test system. The method can include receiving a test packetized data stream, at block  502 . The test packetized data stream can be received by any of the measurement systems or be received and forwarded by a capture device to its corresponding measurement system. 
     The method can also include performing a test on the test packetized data stream, at block  522 . Many different tests can be performed while the test packetized data stream is being received or thereafter. A test can include monitoring a performance parameter or other characteristic of an incoming stream. Thus, the term test is to be construed broadly. 
     In an embodiment, a test packetized data stream corresponding to the test video clip is transmitted and received by the measurement system. The measurement system can process the received stream to generate a transmitted video clip, which can be used as described with a comparison operation described below. Another test may also be performed. For example, the rate at which packets are received may be monitored. In another example, the number of times one or more missing packets are requested by the measurement system or retransmitted by the network equipment along the broadcast transmission path may be measured. In still another embodiment, another parameter may be monitored or a different test may be performed. The information acquired by any of the tests can be used to generate a test result. 
     The method can further include comparing the test result to a reference or prior test result, at block  542 . In one embodiment, the test video clip may have previously been sent from the test controller  402  and received by and stored at a measurement system, such as the measurement system  442 . The test video clip that is locally stored on the measurement system will be referred to as the stored test video clip. The transmitted test video clip can be treated as a test result and the stored test video clip can be treated as a reference. In this particular embodiment, the comparison can be between the transmitted and stored test video clips. 
     In another embodiment, other data can be generated from a comparison operation. In one embodiment, a test video clip, or a portion thereof, can be retransmitted on a regular basis (e.g., hourly, daily, etc.) or irregular basis (e.g., after equipment or software upgrade or replacement, other service or maintenance, after a power outage, or the like). A comparison can include comparing a current reception rate to a prior reception rate to obtain a reception rate difference. In another embodiment, the number of retransmitted packets from a current test packetized data stream can be compared to the number of retransmitted packets from a previous transmission of the same test packetized data stream to obtain a retransmission difference. Each of the reception rate difference and retransmission difference is similar to a first derivative. Either or both differences may be useful to determine if the service provider&#39;s network equipment is drifting or trending in a particular direction. If more data is available, a change between differences can be obtained and would be similar to a second derivative. In still another embodiment, test results can be integrated over time. The significance of the first derivative, second derivative, and integral value will be discussed in more detail later in this specification. For the purposes of this specification, the information corresponding to a first derivative, second derivative, or integral value are considered a particular type of test result. 
     The form of the test results can be varied based on the data collected or the needs or desires of the service provider. The test result can be a measured parameter. In another embodiment, the test result can be a difference or an absolute value of the difference. In still another embodiment, the test result can be normalized or a relative term (e.g., a percentage). 
     In a particular embodiment, the comparison operation is not required and may be omitted or deleted if needed or desired. 
     The method can also include determining whether a test result or information derived from a test result is beyond a limit, at decision tree  544 . Theoretically, the stored and transmitted test video clips are identical. However, if there is a significant amount of noise or other transmission problem, the stored and transmitted test video clips will differ. If the difference between the two test video clips is too great, the difference is beyond the limit. In other embodiments, other test results, such as rates, differences, changes in differences, integral values, and the like, can be used. 
     If the test result or information derived from the test result is beyond the limit (“Yes” branch from decision tree  544 ), the measurement system can generate a notice. The notice can include an alarm, an alert, or other warning, a test result or information derived from a test result, other suitable information that may be useful in diagnosing or performing a corrective measure, or any combination thereof. The notice can be sent from the measurement system and received by the test controller  402 . The test controller  402  may forward the notice to the broadcast management system, an administrator, another suitable recipient, or any combination thereof. The broadcast management system, administrator, or other recipient can take appropriate action based on information within the notice. 
     If the test result or information derived from the test result is not beyond the limit (“No” branch from decision tree  544 ) or after generating the notice at block  546 , a determination can be made whether another test is to performed on the test packetized data stream, at decision tree  548 . If another test is to be performed (“Yes” branch from decision tree  548 ), the method can be iterated starting at block  522 . Otherwise (“No” branch from decision tree  548 ), a determination is made whether another test packetized data stream is to be received, at decision tree  562 . If another test packetized data stream is to be performed (“Yes” branch from decision tree  562 ), the method can be iterated starting at block  502 . Otherwise (“No” branch from decision tree  548 ), the method may end. 
     The information corresponding to first derivatives, second derivatives, and integral values can be useful with the method, even if thresholds are not exceeded. The information corresponding to the first derivative can be used to determine how quickly and in which direction the broadcast network is trending. A notice may or may not be generated on the basis of the first derivative information. In another embodiment, information from the second derivative may be used to determine if the notice should be generated or if action should be taken by the service provider. For example, if a second derivative is negative, the system may be trending away from its original or prior state; however, at a slower rate. No correction action may be performed, as a correction may cause the system to become more unstable than if the system were allowed to continue without any corrective action. 
     The integral value can be useful in determining a cumulative error or other effect over time. If the information corresponding to the first derivative is relatively low, and the second derivative is close to zero, the cumulative effect may still be significant. For example, the rate at which packets are received may be declining at 0.2% per hour. While the rate of decline by itself for any one-hour time interval may not be significant, over a 12-hour period, the rate may have declined by 2.4%. Even if the rate of receiving packets is acceptable and the hourly rate of change in the rate is acceptable, the integral value can provide information indicating that corrective action should be taken. 
     The derivative and integral control can be used as an alternative or in conjunction with other control methods. The comparison between transmitted and stored test video clips can still be performed. The derivative and integral control methods can be used to indicate when corrective action should or should not be taken and may indicate that corrective action should be taken sooner as compared to a simple test video clip comparison. 
     The system and components (e.g., the test controller  402 , the source system  422 , the measurement system  442 , etc.) described herein can be implemented using a general computing system, and the methods described can be carried out by the general computing system that may be located within the network. 
       FIG. 6  includes an illustrative embodiment of a general computer system  600 . The computer system  600  can include a set of instructions that can be executed to cause the computer system  600  to perform any one or more of the methods or computer based functions disclosed herein. The computer system  600  may operate as a standalone device or may be connected, such as by using a network, to other computer systems or peripheral devices. 
     In a networked deployment, the computer system may operate in the capacity of a server or as a client user computer in a server-client user network environment, or as a peer computer system in a peer-to-peer (or distributed) network environment. The computer system  600  can also be implemented as or incorporated into various devices, such as a desktop PC, a laptop PC, an STB, a personal digital assistant (“PDA”), a mobile device, a palmtop computer, a laptop computer, a desktop computer, a communications device, a wireless telephone, a wireline telephone, a control system, a camera, a scanner, a facsimile machine, a printer, a pager, a personal trusted device, a web appliance, a network router, switch or bridge, or any other machine capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that machine. In a particular embodiment, the computer system  600  can be implemented using electronic devices that provide voice, video or data communication. Further, while a single computer system  600  is illustrated, the term “system” shall also be taken to include any collection of systems or sub-systems that individually or jointly execute a set, or multiple sets, of instructions to perform one or more computer functions. 
     The computer system  600  may include a processor  602 , such as a central processing unit (“CPU”), a graphics processing unit (“GPU”), or both. Moreover, the computer system  600  can include a main memory  604  and a static memory  606  that can communicate with each other via a bus  608 . As shown, the computer system  600  may further include a video display unit  610 , such as a liquid crystal display (“LCD”), an organic light emitting diode (“OLED”), a flat panel display, a solid state display, or a cathode ray tube (“CRT”). Additionally, the computer system  600  may include an input device  612 , such as a keyboard, and a cursor control device  614 , such as a mouse. The computer system  600  can also include a disk drive unit  616 , a signal generation device  618 , such as a speaker or remote control, and a network interface device  620  to communicate with a network  626 . In a particular embodiment, the disk drive unit  616  may include a computer-readable medium  622  in which one or more sets of instructions  624 , such as software, can be embedded. Further, the instructions  624  may embody one or more of the methods or logic as described herein. In a particular embodiment, the instructions  624  may reside completely, or at least partially, within the main memory  604 , the static memory  606 , and/or within the processor  602  during execution by the computer system  600 . The main memory  604  and the processor  602  also may include computer-readable media. 
     Embodiments described herein can be used to allow automatic testing of a video system. Because a test video clip can be transmitted as a test packetized data stream over a dedicated test channel, similar to broadcast video content received over an entertainment broadcast channel, the testing more closely replicates the conditions that can affect a customer&#39;s quality of experience at the CPE  262 . Measurement systems can be placed at strategic points to detect more precisely where problems are first experience within the broadcast portion of the service provider&#39;s access network. Corrective actions can be taken before a customer detects a significant degradation in the customer&#39;s quality of experience at the CPE  282 . In another embodiment, diagnosing and isolating a cause of a problem may occur more quickly because the test controller  402  can obtain information from the measurement systems in real time. 
     The system can also act proactively. The information can be examined for trends, cumulative effects, or other patterns to reduce the likelihood that a relatively minor issue does not become a problem. The test system can process the information and determine whether or not further action should be taken and can work in conjunction with the system that controls the broadcast portion of the service provider&#39;s access network to make adjustments or intentionally not make adjustments. 
     Many different aspects and embodiments are possible. Some of those aspects and embodiments are described below. After reading this specification, skilled artisans will appreciate that those aspects and embodiments are only illustrative and do not limit the scope of the present invention. 
     In a first aspect, a video system can be used in conjunction with a packet-switched network operable to transmit video content to end-user equipment. The video system can also include a first source system coupled to first network equipment at a first point where broadcast video content would normally be introduced into the packet-switched network, wherein the first source system is operable to provide a first test packetized video data stream to the first network equipment. The video system can also include a first measurement system coupled to second network equipment at a second point along a broadcast transmission path between the first transmission equipment and the end-user equipment, wherein the first measurement system is operable to generate a first measurement associated with the first test packetized video data stream as received from the second network equipment. The video system can further include a test controller coupled to the first source and first measurement systems, wherein the test controller is operable to control the first source system and to receive information regarding the first test packetized video data stream from the first measurement system. 
     In an embodiment of the first aspect, the video system further includes a second measurement system coupled to third network equipment at a third point along the broadcast transmission path between the second transmission equipment and the end-user equipment, wherein the second measurement system is operable to generate a second measurement associated with the first test packetized video data stream as received from the third network equipment. In another embodiment, the video system further includes a second source system coupled to third network equipment at a third point where different broadcast video content would normally be introduced into the packet-switched network, wherein the second source system is operable to provide a second test packetized video data stream to the third network equipment, and wherein the first and third points are at different sites. In still another embodiment, the first point is at a super head office or a video head office. 
     In a further embodiment of the first aspect, the video system further includes a capture device coupled to third network equipment at a third point along the broadcast transmission path between the first transmission equipment and the end-user equipment, wherein the capture device is operable to receive the first test packetized video data stream from the third network equipment. The video system still further includes a second measurement system coupled to the capture device, wherein the second measurement system is operable to generate a second measurement associated with the first test packetized video data stream as received from the capture device, and wherein the test controller is coupled to the second measurement system and operable to receive information regarding the first test packetized video data stream from the second measurement system. In a particular embodiment, the third network equipment includes a video access device, wherein the capture device is physically separate from the video access device, and wherein the capture device and the video access device are disposed within a housing that is exposed to an outdoor ambient. In a more particular embodiment, the second measurement system is located at a site remote to the housing. In another more particular embodiment, another capture device does not lie between the second network equipment and the first measurement system. 
     In a second aspect, a video system can be used in conjunction with a packet-switched network operable to transmit video content to first end-user equipment via a broadcast transmission path. The video system can also include a first capture device located outside the broadcast transmission path and operable to receive a first test packetized data stream from network equipment at a first intermediate point between a first injection point for the first test packetized data stream and the first end-user equipment. The video system can further include a first measurement system located outside the broadcast transmission path and coupled to the first capture device, wherein the first measurement system is operable to access the first test packetized video data stream from the first capture device and generate a first measurement associated with the first test packetized video data stream. 
     In an embodiment of the second aspect, the video system further includes a second capture device operable to receive a second test packetized data stream from the network equipment at a second intermediate point between a second injection point for the second test packetized data stream and second end-user equipment, wherein the first measurement system is operable to access the second test packetized video data stream from the second capture device and generate a second measurement associated with the second test packetized video data stream. In a particular embodiment, the first and second capture devices are located in different offices, or the first and second capture devices are coupled to different video access devices, wherein the different video access devices are remotely located with respect to each other. 
     In another embodiment of the second aspect, the video system further includes a second capture device operable to receive a second test packetized data stream from the network equipment at a second intermediate point between a second injection point for the second test packetized data stream and second end-user equipment. The video system also includes a third capture device operable to receive a third test packetized data stream from the network equipment at a third intermediate point between a third injection point for the third test packetized data stream and third end-user equipment. The video system further includes a second measurement system located outside the broadcast transmission path and coupled to the second and third capture devices, wherein the second measurement system is operable to access the second test packetized video data stream from the second capture device and the third test packetized video data stream from the third capture device, wherein the second measurement system is different from the first measurement system. In a particular embodiment, the first, second, and third capture devices are different capture devices, and the first, second, and third injection points are a same injection point. 
     In a third aspect, a video system can be used in conjunction with a packet-switched network operable to transmit video content to end-user equipment. The video system can include first equipment operable to associate a first packetized video data stream with an entertainment broadcast channel, second equipment operable to transmit the first packetized video data stream over the entertainment broadcast channel, third equipment operable to associate a second packetized video data stream with a dedicated test channel, and fourth equipment operable to transmit the second packetized video data stream over the dedicated test channel. 
     In an embodiment of the third aspect, the packet-switched network is normally operable to transmit test packetized video data streams over the dedicated test channel at substantially all times. In another embodiment, the packet-switched network is configured such that only test packetized video data streams are transmitted over the dedicated test channel. In still another embodiment, the packet-switched network is operable to transmit the second packetized video data stream to the end-user equipment. In a further embodiment, wherein the second and fourth equipment are located within a same office. 
     In a fourth aspect, a method of testing can be performed on a video system used in conjunction with a packet-switched network. The method can include receiving a packetized video data stream at a first site along a transmission path of the packet-switched network during a first time period, and performing a test on the packetized video data stream received during a first time period to generate a first test result. The method can also include receiving the packetized video data stream at the first site along the transmission path during a second time period that is after the first time period, and performing the test on the packetized video data stream received during the second time period to generate a second test result, wherein performing a test on the packetized video data stream received during a first time period to generate a first test result and performing the test on the packetized video data stream received during the second time period to generate a second test result are performed using a same test equipment. The method can further include comparing the first and second test results to generate a first difference. 
     In an embodiment of the fourth aspect, the method further includes generating a notice when the first difference is beyond a threshold limit. In another embodiment, the method further includes receiving the packetized video data stream at the first site along the transmission path during a third time period that is after the first and second time periods, performing the test on the packetized video data stream received during the third time period to generate a third test result, and comparing the second and third test results to generate a second difference. In a particular embodiment, the method further includes generating a notice when a change between the first and second differences is beyond a threshold limit. 
     In a further embodiment of the fourth aspect, the method further includes receiving the packetized video data stream at the first site along the transmission path during a third time period that is after the first and second time periods, performing the test on the packetized video data stream received during the third time period to generate a third test result, and integrating the first, second, and third test results over time to generate an integral value. In a particular embodiment, the method further includes generating a notice when integral value is beyond a threshold limit. 
     A processor readable medium can include code. The code can include instructions for a processor to carry out any part or all of the methods described herein. 
     Note that not all of the activities described above in the general description or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed are not necessarily the order in which they are performed. 
     The illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The illustrations are not intended to serve as a complete description of all of the elements and features of apparatus and systems that utilize the structures or methods described herein. Many other embodiments may be apparent to those of skill in the art upon reviewing the disclosure. Other embodiments may be utilized and derived from the disclosure, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. Additionally, the illustrations are merely representational and may not be drawn to scale. Certain proportions within the illustrations may be exaggerated, while other proportions may be minimized. Accordingly, the disclosure and the figures are to be regarded as illustrative rather than restrictive. 
     The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b) and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description of the Drawings, various features may be grouped together or described in a single embodiment for the purpose of streamlining the disclosure. This disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter may be directed to less than all of the features of any of the disclosed embodiments. Thus, the following claims are incorporated into the Detailed Description of the Drawings, with each claim standing on its own as defining separately claimed subject matter. 
     The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the scope of the present disclosed subject matter. Thus, to the maximum extent allowed by law, the scope of the present disclosed subject matter is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.