KR20090021338A - Local digital video distribution system for cable - Google Patents

Abstract

An apparatus for use in a cable system comprises a port for receiving a downstream cable transmission; a demodulator for receiving an upstream signal for providing a demodulated signal; and a modulator for modulating the demodulated signal for providing a downstream signal for addition to the received downstream cable transmission.

Description

Local Digital Video Distribution System for Cables {LOCAL DIGITAL VIDEO DISTRIBUTION SYSTEM FOR CABLE}

TECHNICAL FIELD The present invention generally relates to communication systems, and more particularly to cable television systems.

Current cable television (TV) systems provide customers with a number of services such as TV programming (both network and region), pay-per-view programming, and Internet access. One example of a cable TV system is a hybrid fiber / coax based network with a bandwidth capacity of 750 MHz or more to deliver these services to subscribers of these services. This bandwidth capacity is generally partitioned between downstream and upstream channels. This downstream channel delivers downstream Internet data communication as well as TV programming to each subscriber, while the upstream channel carries upstream Internet data communication from each subscriber.

The above described distribution of cable TV bandwidth to the downstream and upstream channels does not efficiently support local service delivery because any data communicated between endpoints must pass through the cable head-end. . Therefore, in accordance with the principles of the present invention, an apparatus for use in a network includes a port for receiving downstream network transmissions; A demodulator for receiving an upstream signal for providing a demodulated signal; And a modulator to modulate the demodulated signal to provide the downstream signal for addition to the received downstream network transmission.

In an exemplary embodiment in accordance with the principles of the present invention, the apparatus is connected to a video server connected to a cable system that receives upstream transmissions carrying video content and retransmits the received upstream transmissions downstream to at least one cable endpoint of the cable system. Where the server is located downstream from the head end of the cable system.

In yet another exemplary embodiment in accordance with the principles of the present invention, the apparatus receives an upstream transmission carrying video content by using at least one video channel of the cable system and is received upstream to at least one cable endpoint of the cable system. A video server connected to a cable system that redirects transmissions downstream.

1 illustrates an exemplary cable system in accordance with the principles of the present invention.

2 illustrates an exemplary frequency spectrum in accordance with the principles of the present invention.

3 illustrates an exemplary embodiment of a server in accordance with the principles of the invention.

4 illustrates another exemplary cable system in accordance with the principles of the present invention.

5-9 illustrate another exemplary embodiment of a server in accordance with the principles of the invention.

10 illustrates another exemplary cable system in accordance with the principles of the present invention.

11 illustrates another exemplary embodiment of a server in accordance with the principles of the invention.

12-14 illustrate bandwidth management in accordance with the principles of the present invention.

15-18 illustrate exemplary embodiments of a programmable bandwidth device in accordance with the principles of the present invention.

19 and 20 illustrate exemplary embodiments of endpoints in accordance with the principles of the present invention.

Except for the concept of the present invention, the components shown in the drawings are well known and will not be described in detail. Also, television broadcasts and receivers are assumed to be familiar in terms of terrestrial, satellite and cable and are not described in detail herein. For example, except for the concept of the present invention, the National Television System Committee (NTSC), Phase Alternation Lines (PAL), SECUal Couleur Avec Memoire (SECAM), Advanced Television Systems Committee (ATSC) and ITU-T J.83 Familiarity is assumed for current and proposed recommendations for television standards such as "Digital multiprogramme system for television, sound and data services for cable distribution." Similarly, apart from the inventive concept, downlink signal and transmission concepts such as satellite transponders, cable head ends, set-top boxes, eight-level residual sidebands (8-VSB), quadrature amplitude modulation (QAM), and wireless Out-of-band control channel and receiver components, such as the frequency (RF) front end, or receiver portions, such as low noise blocks, tuners, and demodulators, are assumed familiar. Similarly, the format and encoding method for generating a transport bit stream (e.g., Moving Picture Expert Group (MPEG) -2 system standard (ISO / IEC 13818-1)) are well known and are known here. It is not described. In addition, it should be noted that the concept of the present invention may be implemented using conventional programming techniques, which are not described herein as above. Finally, like numbers on the drawings indicate like elements. In addition, as used herein, the term “end point” includes, but is not limited to, a station, personal computer, server, set top box, cable modem, and the like.

Referring now to FIG. 1, an exemplary cable system 100 in accordance with the principles of the present invention is shown. In an exemplary embodiment, the cable system 100 is a hybrid-fiber coax (HFC) system. For simplicity, the light portion is not described here. Although the inventive concept is described in terms of coax, the inventive concept is not so limited, and can be extended to the processing of optical fiber signals. The plurality of stations represented by stations 120-1 through 120-6 are connected to the common head end 105 by a resin branch cable network. In view of the present invention, the head end is an example of a controller for a network. Each station is associated with a cable subscriber. Each station comprises, for example, a set top box for receiving video programming, a cable modem for bidirectional data communication to a bidirectional network, for example the Internet. Head-end 105 is a stored program processor-based system and includes at least one processor (e.g., microprocessor) having corresponding memory with transmitters and receivers connected to a cable network (for simplicity, these configurations Elements not shown). First disregarding the component 200, the cable network includes a main coaxial cable 106 having a plurality of tabs 110-1, 110-2 to 110 -N. Each of these tabs is used for a corresponding feeder cable. For example, the tab 110-1 is used for the feeder cable 111-1. For example, feeder cable 111-1 is used for station 120-1 via tab 115-1 and drop 116-1. Each feeder cable is served to one or more stations sequentially through taps and drops. For the purposes of this description, devices, such as taps, drops, and the like, of the cable network 100 are addressable and controllable by the head end 105 via an out-of-band signaling channel (not shown in FIG. 1). Except for the concept of the present invention, the use of out-of-band signaling channels is known to address and control devices in certain parts of the cable network. For example, an out-of-band control channel based on Frequency Shift Keying (FSK) may be used for both addressing and control of devices in a cable network. One such system is the Addressable Multi-Tap Control System available from Blonder Tongue Laboratories.

In the cable system 100, communication between the head end 105 and the various stations takes place in both the upstream and downstream directions. The upstream direction is toward the head end 105 as indicated by the arrow 101 direction, and the downstream direction is towards the station as indicated by the arrow 102 direction. In accordance with the principles of the present invention, the cable system 100 includes a device that provides local service offerings to at least a portion of a cable network without having to pass through the head end 105. As described herein, local service offerings provide video content. This is further illustrated in FIG. 1 by the server 200, which is illustratively located at the starting point of the feeder cable 111-1. However, the concept of the present invention is not limited thereto, and a device including a server function may be located in any part of a cable network. Similarly, the inventive concept is not limited to video and other services may be provided, for example audio content (streaming) may be provided to one or more endpoints of the cable system.

Referring now to FIG. 2 and in accordance with one embodiment of the present invention, multiple communication bands are added to the existing cable frequency spectrum. Generally, the cable system provides services over the upstream band 11 and the downstream band 12. These services include internet communications and television programming. However, to enable peer to peer communication, additional pairs of upstream and downstream bands are now added. These peer-to-peer frequency band pairs are different from the band pairs used by cable systems for Internet communications. By way of example, FIG. 2 illustrates three pairs of peer to peer bands located between upstream band 11 and downstream band 12. However, the concept of the present invention is not limited to this, and more or fewer bands may be used, and their position in the spectrum may vary. It should also be noted that FIG. 2 is not due to constant accumulation, and that a transition region between bands may be required. As shown in FIG. 2, the three pairs of peer to peer bands are B0, B1 and B2. Pair B0 includes upstream band B0u 51, and downstream band B0d 54, pair B1 includes upstream band B1u 52 and downstream band B1d 55, and pair B2 includes upstream band B2u ( 53) and downstream band B2d 56.

Referring back to FIG. 1, the server 200 is located at the endpoint away from the feeder cable 111-1 through an upstream peer-to-peer band (eg, B0u in FIG. 2) as indicated by the dashed arrow 31. (For example, station 120-1). The server 200 converts the frequency of this received signal, changes its direction and directs the communication downstream to the downstream peer-to-peer band (e.g., B0d in FIG. 2) as indicated by the dashed arrow 32. Through the transmission to another user located in the feeder cable (111-1) downstream.

Referring now to FIG. 3, an exemplary embodiment of a server 200 is shown. Server 200 includes directional coupler 205, upstream demodulator 225, and downstream modulator 245. The server 200 is connected to the cable network via a path 201. The upstream signal from drop 201 is received via directional coupler 205, which is provided to demodulator 225 via signal path 214. Demodulator 225 is tuned to the appropriate peer to peer band. This may be accomplished through the out-of-band control channel (not shown in FIG. 3) mentioned above, or may be preconfigured in the server 200. Upstream demodulator 225 demodulates the received upstream signal in the designated peer to peer band (eg, BO) and provides the demodulated signal to downstream modulator 245. This demodulated signal represents a video that may be in a compressed format (eg, MPEG2, H.263, H.264, VC1, or other format). The downstream modulator 245 modulates the demodulated signal to provide the downstream signal 246 in the corresponding peer to peer band (eg, B0d). The downstream signal 246 is reconnected to the drop 201 through the directional coupler 205, for example to send it back downstream for reception by the station 120-2. If necessary, it should be noted that separate decoder and coder functions may be included in the demodulator and modulator, respectively. Alternatively, separate decoders and coders may be added to the embodiment shown in FIG. 3 for further processing of the demodulated signal. For example, server 200 may provide a transcoding function, where upstream video is coded in one video format, while the resulting downstream video is coded in another video format.

As described above, the cable system may have one or more devices that support server functionality located in one or more portions of the cable network. By way of example, FIG. 1 shows a server connected to a feeder cable. The type of server and another exemplary location is shown in FIG. 4. 4 is similar to the component shown in FIG. 1 except for the server 300 used for the feeder cable 111-1. As can be observed, all upstream and downstream communications pass through server 300. An exemplary embodiment of the server 300 is shown in FIG. 5.

Server 300 includes upstream / downstream filter 210, upstream demodulator 225, downstream modulator 245, controller 250, and directional coupler 205. The controller 250 controls various components of the server 300 and is, for example, a microprocessor having a corresponding memory. For simplicity, various control signals from the controller 250 to other of the components of the server 300 are not shown. The operation of server 300 is similar to that described above for server 200 except for the inclusion of upstream / downstream filter 210. In this example, it is assumed that a particular one of the peer to peer bands shown in FIG. 2 is designated for use by the server 300. The upstream / downstream filter 210 has a stop band corresponding to the designated peer to peer band (eg, B0 of FIG. 2). As a result, all downstream signals received via path 316 are first filtered by upstream / downstream filter 210 to route 331 for further transmission downstream via path 211 and directional coupler 205. Provide a filtered signal that is passed to Similarly, all upstream signals received via path 331 are also filtered by upstream / downstream filter 210 before being passed through path 316 for transmission to further upstream. For example, if the server 300 is configured to use only the peer to peer band of FIG. 2 (B0 of FIG. 2), the upstream / downstream filter 210 corresponds to the peer to peer bands B0u and B0d. A stop band is provided to prevent any interference to peer-to-peer transmissions using band B0 on feeder cable 111-1.

Another exemplary embodiment of a server 300 in accordance with the principles of the present invention is shown in FIG. 6. Such a device is designated 300 '. Server 300 'is replaced with upstream / downstream filter 210' by upstream / downstream filter 210 ', and controller 250 sets the filter parameters of upstream / downstream filter 210'. Similar to server 300 except that it allows the system control processor (not shown) (located in head end 105) in the cable network the ability to configure server 300 '. In particular, the controller 250 may respond to the out-of-band signaling channel (indicated by the signal 254) mentioned above to set the filter stop band via the control signal 251 (indicated in dashed line form). In this regard, the out-of-band signaling channel is modified to include predefined instructions associated with other filter settings.

Another exemplary embodiment of a server 300 in accordance with the principles of the present invention is shown in FIG. This device is designated 300 ". Server 300" is similar to server 300 'except for the addition of components 220, 265 and 270. This exemplary embodiment provides a server that inserts local video into an existing channel of a downstream video transport stream in contrast to the peer to peer band usage described above. By way of example, this use of an existing channel may be predetermined, for example channel 81 is designated for local video. As above, the directional coupler 215 provides a downstream signal to the component 220, which demodulates the downstream video transport portion of the signal to provide a digital traffic signal to the multiplexer (mux) 265. . As is known in the art, digital transport signals represent multiple video channels. The mux 265 replaces the video content on the designated channel with the video content transmitted by the demodulated signal from the upstream demodulator 225 to provide a new video transport signal to the component 270. Component 270 modulates this signal to provide a new downstream video transport signal for reception by one or more of the downstream stations on this portion of the cable network. Thus, these downstream stations must simply tune their TV or set top box to the designated video channel for viewing local video. In this embodiment, the upstream / downstream filter 210 passes further downstream channels (eg, these bands designated for providing Internet services) along the downstream through the directional coupler 205.

Another exemplary embodiment of a server 300 in accordance with the principles of the present invention is shown in FIG. 8. This device is designated 300 "'. Server 300"' is similar to server 300 "except for the addition of components 230 and 235. These components provide transcoding functionality. In other words, the local video content can be received in any one of a number of compressed formats (except MPEG2) Video decoder 230 suitably decompresses the demodulated signal provided by upstream demodulator 225 and MPEG2. It provides an uncoded signal to coder 235, which encodes the video in MPEG2 format for retransmission downstream downstream, although shown as separate components, decoding and coding functions may be part of each demodulator and modulator. Note that it can be.

Another exemplary embodiment of a server in accordance with the principles of the invention is shown in FIG. 9. This device is designated 500 in FIG. 9. The server 500 includes switches 315, 320, and 325, up / down band stop (BS) filters 310, a controller 305, a divider 330, and a server 200. The latter is the same as the server 200 of FIG. 3, except that the directional coupler 205 of FIG. 3 is connected to the path 204 shown in FIG. 9. The controller 305 is capable of configuring the server in a system control processor (not shown) in the cable network (e.g., located within the head end 105), e.g., frequency (whether the server is on or off). For example, which peer to peer band to use) and / or the ability to establish a gain setting. By way of example, in this embodiment, the controller 305 controls whether the server function is enabled for the feeder cable 111-1. In particular, controller 305 responds to the out-of-band signaling channel (indicated by signal 304) mentioned above to enable or disable server functionality at server 500 via switches 315, 320, and 325. . In this regard, the out-of-band signaling band has been modified to include predefined instructions related to enabling or disabling the server at a particular device. When the server function is disabled, the switches 315 and 320 allow all upstream signals received via the path 331 from the feeder cable 111-1 to be passed to the main coaxial cable 106 through the divider 330. It is composed. Similarly, all downstream signals received from the main coaxial cable 106 via the path 316 are passed through the divider 330 to the feeder cable 111-1. In addition, the switch 315 disconnects the server 200 from the network. However, when the server function is enabled, all upstream signals received from the feeder cable 111-1 via the path 331 are also provided to the server 200 via the switch 325. Server 200 functions to provide local video signals back downstream, as described above. Moreover, when the server is enabled, the up / down BS filter 310 is now switched to further filter both upstream and downstream communications. BS filter 310 has a stop band corresponding to the peer to peer band used by server 200. For example, if the server 200 is configured to use only the peer to peer band B0 of FIG. 2, the up / down BS filter 310 may use the band B0 on the feeder cable 111-1. It has a stop band corresponding to the peer to peer band B0 to prevent any interference to peer to peer transmission.

Another exemplary embodiment of a cable system according to the principles of the present invention is shown in FIG. This figure is similar to FIG. 4 except for a tab 400 that includes server functionality. Tab 400 is shown in more detail in FIG. 11. As can be observed from FIG. 11, tab 400 includes server 300 (described above) of FIG. 3 (or servers of FIGS. 6, 7, 8, and 9). Thus, tab 400 in accordance with the principles of the present invention is used to provide server functionality in a cable system.

As described above, a peer to peer channel may be used to deliver local service as illustrated in FIG. These peer-to-peer channels are different from existing upstream and downstream used to carry programming and Internet communications in cable systems. Alternatively, existing channels used to convey downstream programming can also be used in accordance with the principles of the present invention. This is illustrated in Figures 7 and 8 in that it uses pre-existing video channels. In addition, because it is difficult to reuse only any downstream channels, a band select amplifier can be used that allows the boundary between upstream and downstream communications to be moved through other parts of the cable network. According to the principles of the present invention, the bandwidth of the cable system 100 is divided into a number of bands as shown in FIG. There are a number of programmable bands, represented by the fixed upstream band B0 11 for upstream, the fixed downstream bands B3 12, B1 71 and B 72 for downstream communication. By way of example, the programmable bands are arranged between upstream band B0 and downstream band B3, but the invention is not so limited with respect to the location of these bands or their number. As a result, the boundary between upstream and downstream communications in certain parts of the cable network may be shifted. This is illustrated by FIGS. 13 and 14. In FIG. 13, the upstream communication initially includes bands B1 and B2. In FIG. 14, it can be observed that one of the upstream bands, B2 72, is now allocated for downstream communication. In view of these figures, the suffixes "u" or "d" are suitably appended to the band B1 or B2 to further indicate whether B1 or B2 are allocated upstream or downstream, respectively.

Referring now to FIGS. 15 and 16, an exemplary block diagram of a filter 210 for use in the server embodiment described above is shown. FIG. 15 illustrates the downstream filter portion of filter 210, which, together with multiplexers (switches) 515 and 535, controlled via control signal 251 described above, filter banks 520, 525, and 530. It includes. As shown in FIG. 15, the multiplexer is used to route a signal through one of the filters as determined by control signal 251 by control signal 251. Each filter has a pass band corresponding to one of the downstream bands shown in FIG. 12 (again, the suffix d indicates that the filter is in the download path). For example, if only filter 520 is selected, any downstream communication using bands B1 and B2 from the head end is blocked, which frees these bands for use by server 300. In this regard, the out-of-band signaling channel has been modified to include predefined instructions related to the particular bandwidth configuration.

Similar mention applies to FIG. 16, which illustrates the upstream filter portion of filter 210. This portion includes filter banks 570, 575 and 580, with multiplexers (switches) 565 and 585 controlled via control signal 251. As shown in FIG. 16, the multiplexer is used to route a signal through one of the filters as determined by control signal 251. Each filter has a pass band that corresponds to one of the upstream bands shown in FIG. 12 (again, the prefix u indicates that the filter is in the upstream path).

Another exemplary embodiment of a filter 210 in accordance with the principles of the present invention is shown in FIGS. 17 and 18, which shows alternative embodiments for the downstream and upstream portions of the filter 210. In FIG. 17, the downstream filter portion includes divider 805, filter sets 810, 815 and 820, multiplexers (switches) 825 and 830, and combiner 835. The downstream signal 316 is applied to the divider 805, which divides this signal for application to each filter. As shown in FIG. 17, filter 810 has path band B3, filter 815 has path band B2 (again, suffix d indicates that the filter is in the downstream path), filter 820 Has a path band B1. Multiplexers 825 and 830 are controlled via control signals 251 to pass or block signals for application from their respective filters to combiner 835. The latter combines any applied signal and forms the downstream signal 211.

Similarly, in FIG. 18, the upstream portion includes divider 855, filter sets 860, 865 and 870, multiplexers (switches) 875 and 880, and combiner 885. Upstream signal 211 is applied to divider 855, which divides the signal for application of each filter. As shown in FIG. 18, filter 860 has path band B0, filter 865 has path band B1 (again, the prefix u indicates that the filter is in the upstream path), and filter 870 Has a pass band B2. Multiplexers 875 and 880 are controlled via control signal 251 to pass or block signals for application from each of these filters to combiner 885. The latter combines any applied signal and forms upstream signal 311

As described above, the inventive concept provides an alternative approach for providing local service offerings to customers in a cable network. Thus, it is possible to provide location specific information, such as video from the security office of an apartment complex, to other parts of the cable network, or to provide important news and information to local groups on one part of the cable network.

Referring now to FIG. 19, an exemplary embodiment of an apparatus for use in, for example, one or more stations of the cable system of FIG. 1 is shown. Apparatus 600 includes a camera 605, a video encoder 610, and an upstream modulator 620. The physical location of the various components may vary, ie the camera 605 need not be co-located with the upstream modulator 620. Alternatively, one or more of the components shown in FIG. 19 may be arranged in a single unit (eg, in a video camera including upstream modulator 620). Camera 605 provides a video signal to video encoder 610. The latter compresses this video signal into a compressed video format (e.g. MPEG2, H.263, H.264, VC1 or other format). This compressed video is provided to upstream modulator 620, for example, for modulation in an upstream channel suitable for communication to server 200 (or server 300, etc.).

Another exemplary embodiment of a cable modem according to the principles of the present invention is shown in FIG. 20. Cable modem 700 includes a peer-to-peer (P2P) modulator 705, a P2P demodulator 710, a downstream demodulator 715, and an upstream demodulator 720. Cable modem 700 is connected to the cable network through drop 701, divider 85, and path 704. Splitter 85 also provides cable signal 702 to other equipment located at the station, such as a set top box (not shown). The upstream modulator 720 and the downstream modulator 715 function as is well known in the art and allow users to have Internet services (eg, a browser located on a personal computer (PC)) (not shown). Makes it possible to execute P2P modulator 705 and P2P demodulator 710 provide the peer-to-peer connectivity mentioned above and are configurable in one or more of the peer-to-peer bands (eg, as illustrated in FIG. 2). These settings may be determined in software as an option that the user sets, via a PC connected to the cable modem 700. In addition, the PC may store address information for specific members of a peer to peer network, where each address is associated with a particular peer to peer band. Upstream peer to peer communication is provided to the P2P modulator 705 via signal 706, which demodulates the received signal in the designated peer to peer band. As described herein, peer to peer communication includes not only messaging, but also, for example, broadcast messages, multi-casting, and the like. Downstream peer-to-peer communications include messaging as well as broadcast messages, multicasting, and the like, for example. For example, a user can stream content from one endpoint to one or more other endpoints of a cable system in accordance with the principles of the present invention. This content may be video, audio, or the like. Moreover, although the concept of the present invention has been described in terms of application to conventional cable systems, the concept of the present invention is not so limited and applicable to any network type, even for example a home network, a campus network, or the like.

As above, the foregoing descriptions merely illustrate the principles of the present invention and those skilled in the art, although not explicitly described herein, may embody the principles of the present invention and invent numerous alternative devices that fall within the spirit and scope thereof. Will understand. For example, although illustrated in terms of separate functional components, these functional components may be implemented in one or more integrated circuits (ICs). Similarly, although shown as a separate component, any one or all of the components may be implemented as a stored program control processor, eg, a digital signal processor (DSP) or microprocessor executing the corresponding software. . For example, separate modulator and demodulator functions shown in FIG. 3 may be located in one or more DSPs. Moreover, although shown in a particular configuration, the components therein may be distributed to other units in any combination thereof. For example, a cable modem can be part of a personal computer. Therefore, it should be understood that numerous modifications may be made to the exemplary embodiments and that other apparatus may be invented without departing from the spirit and scope of the invention as defined by the appended claims.

The present invention is generally applicable to communication systems, and more particularly to cable television systems.

Claims (24)

As a device for use in a network, A port for receiving downstream network transmissions; A demodulator for receiving an upstream signal and providing a demodulated signal; And A modulator that modulates the demodulated signal to provide a downstream signal for addition to a received downstream network transmission Including, the apparatus for use in the network. The method of claim 1, Further comprising a filter for filtering the received downstream network transmission prior to the addition of the downstream signal, the filter having a stop band covering at least one frequency range of the downstream signal. Device for use. The method of claim 2, And the stop band of the filter is adjustable. The method of claim 1, The demodulator comprises a decoder for use in decoding the coded content in the received upstream signal, And the modulator comprises a coder for use in coding the decoded content. The method of claim 4, wherein And the content is video. The method of claim 5, wherein And the coder is an MPEG2 coder. The method of claim 1, A demodulator for demodulating a video transport portion of a received downstream network transmission to provide a video transport signal representative of a plurality of video channels; And And a multiplexer for combining the demodulated signal and the video transport signal prior to modulation by the modulator. The method of claim 7, wherein And wherein the multiplexer replaces at least one of the video channels with a demodulated signal. The method of claim 1, A device for use in a network that is part of a tap for use in a network. The method of claim 1, And a network control interface responsive to a control signal that enables or disables the modulator. The method of claim 10, And the control signal is an out of band control signal. The method of claim 1, And the network is a cable network. As a method for use in a device of a system, Receiving a downstream network transmission; Receiving an upstream signal for providing a demodulated signal; And Modulating the demodulated signal to provide a downstream signal for addition to a received downstream network transmission And a method for use in a device of the system. The method of claim 13, Filtering the received downstream network transmission prior to the addition of the downstream signal, wherein the filter has a stop band covering at least one frequency range of the downstream signal. Way for you. The method of claim 14, The stop band of the filter is adjustable, the method for use in a device of the system. The method of claim 13, The demodulating comprises decoding the coded content in the received upstream signal, And wherein the modulating comprises coding the decoded content. The method of claim 16, And the content is video. The method of claim 17, And wherein said coding performs MPEG2 coding. The method of claim 13, Demodulating the video transport portion of the received downstream network transmission to provide a video transport signal representative of the plurality of video channels; And Combining the video demodulated signal with the demodulated signal prior to modulation by the modulator. The method of claim 19, The combining step replaces at least one of the video channels with the demodulated signal. The method of claim 13, And the device is part of a tap for use in a network. The method of claim 13, Receiving a control signal for enabling or disabling the device. The method of claim 22, And the control signal is an out-of-band control signal. The method of claim 13, And the network is a cable network.

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