WO2005076625A1

WO2005076625A1 - Method for the transmission and distribution of digital television signals

Info

Publication number: WO2005076625A1
Application number: PCT/US2004/040223
Authority: WO
Inventors: Scott Beaudoin; Scott Jones; Scott Brillhart; Michael Brown; Ryan Korte
Original assignee: Wiltel Communications Group, Llc,
Priority date: 2004-01-30
Filing date: 2004-12-02
Publication date: 2005-08-18
Also published as: EP2290981A3; US10158924B2; US20190124406A1; EP1714487B1; EP1714487A1; EP2290981A2; US10827229B2; US20120219012A1; CA2554881A1; EP2290981B1; US8175020B2; US20050169314A1; CA2554881C

Abstract

A system for the end-to-end delivery of digital television signals. In a preferred embodiment a digital television signal is: received from production equipment typically in HD format at approximately 1.4 gigabits per second (Gbbps); the received signal is transmitted to a venue point-of-presence; converted for transmission via a 270 Mbpc local loop; transmitted to a fiber network point of presence/video service edge; packetized into TCP/IP packets in a video gateway; and routed to one or more destination addresses via the fiber network; received at one or more video service edge destinations; converted to a digital television format, typically SDI; and either transmitted via a second 270 Mbps local loop for delivery to a customer site and subsequent conversion to a 1.4 Gbps HD signal, or converted directly to a 1.4 Gbs HD signal at the receiving video service edge.

Description

METHOD FOR THE TRANSMISSION AND DISTRIBUTION OF DIGITAL TELEVISION SIGNALS

BACKGROUND OF THE INVENTION

1. Field of the Invention The present invention relates to a method for the transmission and distribution

of digital television (DTV) signals. More particularly, but not by way of limitation,

the present invention relates to a method for converting DTV signals to a format for

transmission over a communication network, and transmitting the signal via the

communication network to a remote location.

2. Background of the Invention While the quest for high-definition television ("HDTV" or "HD") has been

hampered by the lack of a single standard, resistance by the broadcast industry to implementation, and a substantial price disparity at the consumer level, mandates from

the Federal Communication Commission are forcing broadcasters and equipment

manufacturers to transition from conventional analog transmission to digital television

transmission. These mandates are certain to finally usher in the era of DTV,

improving the quality of standard definition television ("SDTV" or "SD") and advancing the cause of HDTV. As digital programming becomes more prevalent, the

need for infrastructure for the production and distribution of digital programming

becomes more pressing. Most of the existing infrastructure was developed for the distribution of analog

video, and an assortment of options presently exist as to the production and distribution of analog programming. Distribution via satellite, microwave link, or

digitally through a fiber network, or even over conventional wires are common place.

Arrangements can be made for a live broadcast from almost anywhere in the world with little more than a few hours notice. Unfortunately, while the video signal may be

digitized over some portion of its path, it starts out as an analog signal and is delivered

as an analog signal. End-to-end delivery ofdigital video is just beginning to evolve. Presently, satellite transponders are available which will carry DTV signals,

however the issue of bandwidth is, at best, confusing. Data rates vary widely from

satellite-to-satellite and transponder sharing further complicates the issue. A producer

who plans on sending a DTV signal via satellite must negotiate bandwidth as well as

cost. Regardless of these issues, satellite bit rates for a single transponder are limited

to roughly 100 Mbps. As a result, for satellite transmission of DTV, some form of

compression is virtually always required. For transmission of HDTV signals via

satellite, substantial compression is absolutely necessary. As discussed further

hereinbelow, compression raises additional concerns.

Compression techniques can be broadly divided into two categories: 1) lossy

techniques; and 2) non-lossy techniques. Generally speaking, lossy compression

techniques compress a signal in a manner designed to faithfully reproduce the content

at the receiving end while not faithfully recreating the original digital signal. Non-

lossy compression techniques faithfully reproduce the original data stream, thus

ensuring that the content at the receiving end is identical to that at the transmitting

end. Lossy compression techniques have emerged as the standard simply because

such schemes provide significantly higher rates of compression over their non-lossy

counterparts. Many of the aggressive compression schemes employ forward

interpolation which, in terms of video signals, means that the information displayed in

the current video frame is at least partially dependent on information contained in one or more future video frames. The result is that these compression techniques, by

necessity, add delay to the signal. In general terms, as the data rate increases, the amount of compression decreases and the adverse effects of compression, i.e. fidelity

of the output relative to the input and delay, are reduced. Thus, besides bandwidth and cost, a producer must also ensure a chosen

transponder can accommodate the format of the compressed data stream and must

determine if the accumulated delays are acceptable, including the transit time between

the earth and satellite. The round trip distance from the earth to a satellite alone adds

approximately a one-half second delay to a satellite relayed signal. Like satellite transmissions, for the most part terrestrial infrastructure has been

developed around analog video signals. While fiber networks are inherently digital in nature, bit rates offered to video programmers have been driven by traditional quality

video. Simply providing more bandwidth to accommodate HDTV signals is

hampered by any number of bottlenecks, such as: the data rate supported by the link

between a venue and the fiber network, typically supplied by the local telephone

company; the link between the fiber network and the receiving end; or even

bandwidth limitations of various network elements. At many venues, the link

between the venue and the fiber network is actually analog and digitization takes place

at the fiber network point of presence. After digitization, even traditional analog

video signals are sometimes compressed for digital transmission over the network. As

with satellite transmissions, for a given video format, compressing the video signal

reduces quality and introduces delay. Another issue with transmission over terrestrial carriers is reaching multiple

receivers. While satellites cover wide areas by their very nature, terrestrial video links

tend to be point-to-point. While point-to-multipoint distribution is possible with

either wire networks or fiber networks, a route to each receiver must be planned in

advance. For live events, program production typically occurs at the venue, while

commercials are added at a studio or fixed production facility. Thus the possibility exists that there may be a need for point-to-multipoint delivery both for the original

feed from the venue and for the finished programming including commercials. With

millions of dollars of revenue on the line, not only does such an event warrant the

provisioning of dedicated routes in advance, but also the provisioning of redundant

paths to avoid lost programming in the case of a network event such as a fiber cut. Still another issue in producing and distributing television programming is

monitoring the broadcast video, including commercials, at the venue. Even with

analog programming, returning finished video to the production truck is problematic.

If the finished video is transmitted to network affiliates via satellite, a satellite dish

may be used at the venue to receive the signal. Alternatively, if the programming is carried by a local station, the signal can be monitored directly off-the-air. However,

local programming may also include locally inserted commercials or content which

overlaps the network programming. Yet another alternative is to provision identical

infrastructure assets to return the programming as were used to transmit the original

signal. This technique could effectively double the cost of distribution.

Yet another issue in the transmission of digital television signals is

maintaining synchronization between video and audio portions of the signal. Generally speaking, the delays caused by distance and compression are substantially

constant. Once the audio is synchronized to the video, it will stay synchronized.

Problems with synchronization arise when the audio signal takes a different path from

that of the video signal and the delay in one of the paths is variable, or when the delay

introduced through compression is variable.

Thus it is an object of the present invention to provide a system and method for the end-to-end delivery ofdigital television signals.

Thus it is a further object of the present invention to provide a system and

method for the end-to-end delivery of digital television signals with embedded,

synchronized audio programming.

It is yet a further object of the present invention to provide a system and

method for the end-to-end delivery of digital television signals in a point-to-

multipoint environment.

It is yet a further object of the present invention to provide a system and

method for the end-to-end delivery of digital television signals via a network

conducive to automated provisioning of network resources for a given program.

SUMMARY OF THE INVENTION

The present invention provides a system for the end-to-end delivery of digital

television signals. In a preferred embodiment a digital television signal is: received

from production equipment, typically in HD format at approximately 1.4 gigabits per

second (Gbps); the received signal is transmitted to a venue point-of-presence;

converted for transmission via a local digital loop; transmitted to a network point of presence/video service edge; packetized into data packets in a video gateway; and routed to one or more destination addresses via the data network; received at one or

more video service edge destinations; converted to a digital television format,

typically SDI; and either transmitted via a second local digital loop for delivery to a

customer site and subsequent conversion to a 1.4 Gbps HD signal, or converted directly to a 1.4 Gbs HD signal at the receiving video service edge.

In another preferred embodiment TCP/IP packets are transmitted via dedicated

routes which are determined and scheduled prior to the video transmission.

Optionally, when finished programming is returned to the venue, a symmetric path

can be provisioned for the returning program so that the need for duplicate dedicated network assets is reduced and to facilitate point-to-multipoint distribution.

In still another preferred embodiment audio information is encoded in TCP/IP

packets and embedded with video traffic along the same network routes. When routes

are determined in advanced and dedicated to carrying the video program, packets

arrive in the same order as sent, thus ensuring the audio program remains synchronized with the video program.

In still another preferred embodiment television signals are digitally

transmitted end-to-end from a venue to a customer site wherein at least a portion of

the transmission takes place over a multi-protocol label switching ("MPLS") network.

Preferably packetized video information enters the MPLS network through a label

edge router which adds a label to each video packet containing routing information for

the packet. In yet another preferred embodiment, digital video information is carried over

a data network wherein the egress node includes a memory buffer of sufficient length

to remove jitter in the signal caused by routing delays.

Further objects, features, and advantages of the present invention will be

apparent to those skilled in the art upon examining the accompanying drawings and

upon reading the following description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A provides a block diagram of preferred embodiments of digital video outputs at a customer site.

FIG. IB provides a block diagram of a video service edge at a label egress

node in communication with the core MPLS network as employed in the preferred

embodiments of the inventive system.

FIG. 1C provides a block diagram of a video service edge at a label ingress

node in communication with the MPLS core network as employed in the preferred embodiments of the inventive system.

FIG. ID provides a block diagram of a preferred embodiment of digital video

input at a venue.

FIG. IE provides a block diagram of an egress node at a television operations center.

FIG. 2 provides a block diagram of a preferred video management system at a venue.

FIG. 3 provides a block diagram of redundant systems in a label ingress node. DESCRIPTION OF THE PREFERRED EMBODIMENTS Before explaining the present invention in detail, it is important to understand

that the invention is not limited in its application to the details of the construction

illustrated and the steps described herein. The invention is capable of other

embodiments and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.

As will become apparent on reading the description of the preferred

embodiments, while the inventive system is not limited to a single network

architecture, in the preferred embodiments DTV information is transmitted, at least in

part, over a multiprotocol label switching ("MPLS") network. Such networks are well

known in the art and, with the exception of specialty label ingress nodes and label

egress nodes, as discussed further hereinbelow, the MPLS network of the present

invention is conventional in nature. In a MPLS network, packets are assigned a label at an ingress mode. In

practical terms, the label defines a route through the network. At each node, the label

provides an index into a routing table which provides the next network hop and a new

label which is meaningful to the next node of the network. A number of options are

available for label handling at each node. While MPLS networks are designed for fast

routing, the inherent ability to designate and manage routes in advance of even the

first packet of data is of particular interest to the present invention.

Referring now to the drawings, wherein like reference numerals indicate the

same parts throughout the several views, a block diagram of the inventive system for transmitting DTV signals is shown in FIG. 1A-E. Beginning with FIG. ID, digital video, typically HD video, is delivered from a production truck, or other video source,

via conductor 20, which is may be either fiber or copper wire, typically carrying HD at

a data rate of 1.485 Gbps. Typically the digital video stream will be in conformance

with a published standard, such as SMPTE 292 as promulgated by the Society of Motion Picture and Television Engineers.

At a typical venue, conversions are performed at or near the production

equipment. First, if the signal is received optically, the signal is converted to

electrical by distribution amplifier 24. Next the HD signal is encoded at 270 Mbps by

encoder 22 for transmission over cable 26, preferably in either SDI or ASI format.

The conversion from HD to 270 Mbps allows the signal to negotiate throughput

bottlenecks.

As will be appreciated by those skilled in the art, 270 Mbps is a standard SD

data rate and is preferably in conformance with SMPTE 259M, or a similar published

standard. Terms associated with 270 Mbps digital video include "serial data

interface" ("SDI") which generally refers to data in conformance with SMPTE 259M

and "asynchronous serial interface" ("ASI") which generally refers to digital video

compressed according to the DVB standard.

As will also be appreciated by those skilled in the art, the HD-to-SD encoding

and conversion from an optical data stream to an electrical data stream are known in

the art. One such system for performing these operations is the model 7700 HD series

available from Evertz Microsystems, Ltd. of Burlington, Ontario, Canada. Next, an SDI switch 28 allows the digital video signal to be switched between

redundant paths (not shown) in the event of a failure. From switch 28, the video

signal is directed to distribution amplifier 30 for conversion from electrical to optical.

With further reference to FIG. 2, the conversion from electrical to optical overcomes

distance issues within the venue as the signal is transported from the mezzanine level

equipment 106 located at dock 108 to a telecommunication room 104 at the venue

100.

At the telecommunications room, the signal is converted back from an optical signal

to an electrical signal by distribution amplifier 32 and, with further reference to FIG.

IC, transmitted via a 270 Mbps digital loop 34 provided by a local exchange carrier to

a fiber network point-of-presence 40. As discussed hereinabove, preferably the fiber

network is an MPLS network 42. Thus, in a preferred embodiment the network point-

of-presence 40 is a video service edge, which is a specialized label ingress node for

the MPLS network. At video service edge 40, SDI video is delivered to SDI switch 44 which

allows video to be switched between redundant paths 46, 48, and 50. Preferably paths

46, 48, and 50 each include a video gateway 52. A video gateway 52 either: receives

digital video, i.e. SDI or ASI video, and outputs video formatted in TCP/IP packets; or

receives video formatted in TCP/IP packets and outputs video in a selected serial

format such as SDI or ASI. At ingress video node 40, video gateway 52 receives

serial video data and outputs packetized video data. One such video gateway is the

model CX1000 video gateway manufactured by Path 1 Network Technologies, Inc. of San Diego, CA. Along each path 46, 48, and 50, from gateways 52 the signals are sent via

gigabit ethernet links, or similar high speed network, to router 54a. From router 54a

packetized data is sent to label edge router 56a. As discussed above, a label edge

router has the responsibility for tagging incoming packets with labels which ultimately

determine the route taken through the network by the packet. While in an MPLS

network, the destination edge router has the responsibility for initiating the generation

of labels for a given route, it is preferable in the inventive system to schedule the

routes and generate the routing tables in advance of the televised event. Thus, when

video packets arrive at label edge router 56a from gateways 52, router 56a will simply

add a predetermined label and pass the packet along the first network hop on network

42. One router capable of operating as a label edge router and suitable for use with

the present invention is the model M20 router from Juniper Networks, Inc. of

Sunnyvale, California.

With further reference to FIG. IB, wherein the core MPLS network 42 is again

shown, the packetized video data can take one or more routes through network 42.

For purposes of point-to-multipoint transmission, a generic routing encapsulation

("GRE") tunnel 58 is used to essentially create a private network within the larger

network. Packets can also be transmitted from the label edge router 56a at the ingress

node 40 into the network 42 and routed through the network as normal traffic through

connections 62 and 64, keeping in mind that the route is still scheduled and preferably

dedicated to the video programming. Still yet, a direct route 66 between label edge

router 56a and label edge router 56b may be possible. Regardless of the routing method employed, packetized video is delivered to

video service edge 68, a specialized label egress node, at label edge router 56c. In one

preferred embodiment, video at video service edge 68 is handled in a reverse fashion

as that of the label ingress node 40 described above. Data is sent to router 54c,

directed through redundant paths 70, 72, and 74 to video gateways 52 which receive the TCP/TP packets containing video information and restore the SDI or ASI video

signal. Preferably, gateways 52 include a video buffer of sufficient length to eliminate

jitter in the outgoing serial data caused by routing delays in network 42. In the

preferred embodiment the range of accumulated routing delays can be calculated

and/or measured so that the video buffer within gateway 52 can be sized to be no

longer than necessary to remove the worst case potential jitter. As will be apparent to

those skilled in the art, buffer length has a direct impact on delaying the video signal.

Thus the buffer should be of the minimum length required to remove all potential

jitter. From gateways 52 the serial video data is directed to an SDI switch

76 allowing selection of the video from one of paths 70, 72, and 74 for transmission

via 270 Mbps loop 78. Like loop 34 (FIG. ID), 270 Mbps loop 78 is typically

supplied by the local exchange carrier. With further reference to FIG. 1 A, serial video

data is transmitted to a customer facility via loop 78 where a conversion is performed

from SDI or ASI to HD at 1.485 Gbps by convertor 80 and optionally converted to

optical format in distribution amplifier 82.

In another preferred embodiment, where label edge server 56c is at, or near the

customer site, video packets can be delivered from router 54c directly to the customer site via ethernet local loop 84. Packetized video data is then delivered to router 54d,

directed to video gateway 52 along path 86, converted from TCP/TP packets to SDI,

ASI, or the like, in gateway 52 and restored to HD at 1.485 Gbps in decoder 88.

In still another preferred embodiment, an optical fiber 90 connects the fiber

network with the customer site. Data is then routed from router 56c to router 56e. It

should be noted that two options are available. First, router 56c can remain the label

egress node, strip the label from outbound packets and deliver data to router 56e as

TCP/IP packets. Alternatively, router 56e can become the label egress node, receive

MPLS packets from router 56c and locally convert the packets back to TCP/IP. Either

way, TCP/IP packets are delivered to router 54e, and directed to gateway 52 along

path 92. Within gateway 52 the packetized data is restored to an SDI or ASI data

stream and directed to decoder 94. An HD data stream at 1.485 Gbps is then provided

to the customer.

Turning next to FIGS. IB and IE, in many cases it is desirable to

simultaneously deliver the signal to a network operator's television operations control

facility 96. As will be apparent to those skilled in the art, video packets are simply

routed to label edge router 56b where label information is removed from the packet

and the original TCP/IP packet is delivered to router 54b. From router 54b, data is

sent to router 54f and forwarded to video gateways 52 along paths 98, 110, and 112.

As before, gateways 52 restore the original serial video data stream, i.e. SDI, ASI, or

the like, from the received TCP/IP packets. Data is then switched via SDI switch 114

and converted from SD to HD in decoder 116. It should be noted that the system for the delivery of HD signals described above is capable of bidirectional operation. Thus, for example, at a customer site

commercials may be added it the original signal, and re-transmitted via the MPLS

network back to other video service edges on the network. In such a configuration, a

video service edge, i.e. edge 68, may be a label egress node with respect to the

original program and a label ingress node with respect to the fully produced program.

Thus, at the customer site shown in FIG. 1A for example, path 118 could supply SDI

video to gateway 52 which packetizes the signal and forwards it to video service edge

68 via router 54d. It should also be noted that, in terms of point- to-multipoint operation, GRE

tunnel 58 is preferably symmetric in nature, network traffic in one direction follows

exactly the same route as network traffic in the opposite direction. While necessary

for point-to-multipoint operation, an added benefit is that network delays and jitter are

substantial the same in either direction of operation. It should also be noted that inherent in an MPLS architecture is the ability to

schedule routes in advance of the actual data flow through the network. In terms of

high value programming, this allows the provisioning of network resources well in

advance, allowing the network operator to ensure routes are actually available for a

specific event. Turning next to FIG. 2, in a typical configuration, a production truck 102 is

parked at a stadium in an area reserved for television production equipment 108.

Within 300 feet of truck 102, the practical limit for coax transmission of HDTV,

mezzanine level equipment 106 is provided to support the production truck 102. Typically between truck 102 and support equipment 106 there will be: one or more

conventional analog telephone lines 130 for IFB or engineering management from the

customer facility; SDTV transmit line 132 for support of SD and analog broadcasting;

SDTV receive line 134 for receiving fully produced video back from the customer

site; and HDTV transmit line 136 for sending HDTV via the inventive system.

At the mezzanine level equipment 106 an RJ-11 panel 138 is provided for

management of the telephone lines, a power supply 140 for operation of equipment;

and data and fiber management as described above. From the mezzanine level

equipment 106 information is passed to telco room 104 via fiber to overcome the 300

foot limitation of copper coax.

At room 104, POTS lines 142 are connected to the switched telephone public

network, standard television transmit and receive lines, 144 and 146, respectively, are

handled in the conventional manner through a local loop provided by the local

exchange carrier, and control of the system is provided by network connection 148

directed to router 150. HDTV is directed from telco room 104 to the fiber network point-of-presence in the manner described above.

As will be apparent to those skilled in the art, using the venue system

described above, the conventional broadcast is backed up by the HD broadcast in the

event the classic link fails, and the broadcaster can always fall back to SD if the HD

system fails. As will also be apparent to those skilled in the art, the HD signal is never

analog, delivery of the HD video is digital end-to-end. In contrast, presently analog

video is sent from the venue to the network point-of-presence where digitization now

occurs. With reference to FIG. 3, in most cities there are more than one venue which

host events which are likely to be televised. A feature of the inventive system is that

infrastructure is maximized at, and between, video service edges and minimized at the

individual venues. In light of this feature, multiple venues 200 are each served by

individual 270 Mbps loops 202. A single SDI switch 204 can be used at the video

service edge to enable video distribution from any given venue only during an event.

From switch 204, SDI signals are individually packetized at gateways 52 and sent to

router 206 and, in turn, to label edge router 208 and MPLS network 42. End-to-end

control of the system is accomplished via telemetry network 212, which may, in fact,

be a subset of MPLS network 42. It should also be noted that from a video service edge, monitoring can be accomplished by directing packets from a selected source to

gateway 210 which then provides serial video data.

As will be apparent to those skilled in the art, while some compression of the

HD signal is necessary to perform the HD/SD conversion to 270 Mbps to

accommodate the local loop and video gateway, the level of compression required is

relatively small, particularly in light of the fact that the data rate is over twice that

available from a satellite transponder.

Thus, providing a multicast transmission of HD video with the inventive

system involves: converting the signal from HD data rates to SD data rates; converting the signal to optical for transmission within the venue; converting the signal back to

electrical for transmission over a 270 Mbps loop, typically provided by the local

exchange carrier from the venue to a video service edge; converting from a continuous

data stream (SDI) to TCP/IP packets in video gateway; converting the electrical signal to optical; transmitting the packets over a fiber network in a multicast environment;

receiving the packets at one or more video service edges; converting the packets from

optical to electrical; converting from TCP/IP packets to a continuous serial data

stream in a video gateway; decompressing the signal from SD data rates to HD data

rates; and delivering an HD signal to a customer.

Preferably, the transmission of packets over a fiber network includes tagging

each packet with a label containing routing information and transmitting the packet

over an MPLS fiber network.

Optionally, the packets are transmitted via a GRE tunnel in a point-to- multipoint fashion.

It should be noted that while the preferred embodiments were described with

reference to an MPLS fiber network, the present invention is neither limited to MPLS

networks or fiber networks. In fact many types of networks are suitable for use with

the present invention, whether electrical, optical, wireless, or otherwise, and many

protocols can be employed with regard to practicing the present invention and at

various network layers. Thus, by way of example and not limitation, the present

invention may be practiced in ATM networks, IP networks, and the like, and such

networks are within both the scope and spirit of the present invention.

It should also be noted that the term "label edge router" is used with reference to the preferred embodiments which employs an MPLS network. It is contemplated

that when other types of networks are used, routers appropriate for use with the

specific network will also be used. Thus, the term "router" is to interpreted broadly to include not only label edge routers but also to include any type of network router, switch, or the like.

It should be further noted that, while the preferred embodiments are described

with reference to 270 Mbps loops, the invention is also not so limited. As will be

recognized by those skilled in the art, any number of solutions may be available for digital communications between a venue and the video service edge and any such

solution, regardless of the data rate supported, is within the scope and spirit of the

present invention. By way of example and not limitations, other available digital links

may include: fiber optic, coax, twisted pair, a modulated laser beam, microwave or other RF link, etc.

Finally, with regard to the mezzanine level equipment, it should be noted that

the preferred embodiment is discussed in the general environment of a sports arena,

stadium, or the like. As will be apparent to those skilled in the art, the precise

configuration of the venue-side equipment, as depicted in FIG. 2, will depend on the

environment in which it is used, the type of facility, the distance between production

equipment and telecommunication facilities, etc. It is contemplated that adaptations

of the venue-side equipment to accommodate the local environment are likewise

within the scope and spirit of the present invention.

[0061] Thus, the present invention is well adapted to carry out the objects

and attain the ends and advantages mentioned above as well as those inherent therein.

While presently preferred embodiments have been described for purposes of this

disclosure, numerous changes and modifications will be apparent to those skilled in the art. Such changes and modifications are encompassed within the spirit of this invention.

Claims

1. A method for transmitting an HD signal from a source location to a destination location comprising the steps of: (a) at a source location, receiving a source HD signal from a video source at an HD data rate; (b) compressing said HD signal to create a compressed HD signal in an SD format; (c) transmitting said compressed HD signal at an SD data rate from said source location to a first network point-of-presence; (d) in a first video gateway, converting said compressed HD signal into data formatted for transmission via a data network; (e) transmitting said data through a data network to a second network point-of-presence; (f) in a second video gateway converting said data signal into said compressed HD signal at said SD data rate; (g) decompressing said compressed HD signal into a destination HD signal at said HD data rate; and (h) delivering said destination HD signal at a destination location.

2. The method for transmitting a compressed HD signal from a source location to a destination location of claim 1 wherein said first and second network points-of-presence are video service edges.

3. The method for transmitting a compressed HD signal from a source location to a destination location of claim 1 wherein said data formatted for transmission via a network is formatted as TCP/IP packets.

4. The method for transmitting a compressed HD signal from a source location to a destination location of claim 3 wherein said data network is an MPLS network and said first point-of-presence comprises a first label edge router and said second point of presence comprises a second label edge router and wherein step (f) includes the substep of: (f)(i) tagging said TCP/IP packets with a label in said first label edge router, said label defining said route between said first point-of-presence and said second point-of-presence.

5. The method for transmitting a compressed HD signal from a source location to a destination location of claim 4 wherein said route is defined and reserved according to a schedule prior to performing step(a).

6. The method for transmitting a compressed HD signal from a source location to a destination location of claim 4 wherein said route comprises a GRE tunnel.

7. The method for transmitting a compressed HD signal from a source location to a destination location of claim 6 wherein network traffic along said GRE tunnel is bidirectional and symmetric paths through said data network are defined for said network traffic.

8. The method for transmitting a compressed HD signal from a source location to a destination location of claim 7, wherein in step (f), said TCP/IP packets are transmitted in a point-to-multipoint fashion to a plurality of label edge routers.

9. The method for transmitting a compressed HD signal from a source location to a destination location of claim 7 further comprising: (k) transmitting TCP/IP packets containing a return video program through said GRE tunnel from said second point-of-presence to said first point-of-presence.

10. The method for transmitting a compressed HD signal from a source location to a destination location of claim 1 , wherein said second video gateway comprises a video buffer, and step (h) includes the substeps of: (h)(i) in a second video gateway converting said second electrical signal into said compressed HD signal at said SD data rate; and (h)(ii) buffering said compressed HD signal in said buffer to remove jitter from said compressed HD signal.

11. The method for transmitting a compressed HD signal from a source location to a destination location of claim 1, wherein said data network is a fiber network.

12. A method for preparing an HD signal for transmission over a data network including the steps of: (a) receiving an HD signal at a first data rate; (b) converting said HD signal to an SD signal at a second data rate, said second data rate being lower than said first data rate; (c) transmitting said SD signal via a 270 Mbps loop to a network point-of-presence; (d) converting said SD signal into TCP/IP packets in a video gateway for transmission over a data network; and (e) delivering said TCP/TP packets to a router.

13. The method for preparing HD signals for transmission over a data network of claim 12 wherein said first data rate is 1.485 Gbps.

14. The method for preparing HD signals for transmission over a data network of claim 12 wherein said second data rate is 270 Mbps.

15. The method for preparing HD signals for transmission over a data network of claim 12 wherein said first HD signal conforms to SMPTE 292.

16. The method for preparing HD signals for transmission over a data network of claim 12 wherein said first SD signal conforms to SMPTE 259M.

17. The method for preparing HD signals for transmission over a data network of claim 12 wherein said data network is an MPLS network and said router is a label edge router.

18. A system for the end-to-end digital transmission of a video signal comprising: a mezzanine level system comprising: an encoder for compressing an HD signal at a first data rate to an SDI data stream at a second data rate; and a first converter for converting said SDI data stream to an optical signal; a fiber optic link connecting a second converter for converting said optical signal back to said SDI data stream; a first video service edge comprising: an SDI switch for receiving said SDI data stream, said SDI switch connected to said second converter through a 270 Mbps loop; a first video gateway in communication with said SDI switch for receiving said SDI data stream, wherein said SDI data stream is configured by said first video gateway into packets output through a gateway network connection; and a first router in communication with said first gateway network connection to receive said packets and retransmit said packets via a data network; and a second video service edge comprising: a second router, said second router receiving said packets from said data network and outputs said packets through a router output; and a second video gateway in communication with said router output to receive said packets, wherein said second video gateway converts said packets to restore said SDI data stream through a gateway digital output; a decoder for decompressing said SDI data stream into an uncompressed HD signal at said first data rate, said decoder in communication with said gateway digital output for receiving said SDI data stream.

19. The system for the end-to-end digital transmission of a video signal of claim 18 wherein said decoder is located at a customer site and said decoder is in communication with said gateway digital output through a 270 Mbps loop.

20. The system for the end-to-end digital transmission of a video signal of claim 18 wherein said second video gateway is located at a customer site and said second video gateway is in communication with said router output through an ethernet switch loop or ethernet local loop.

21. The system for the end-to-end digital transmission of a video signal of claim 18 wherein said second video service edge is located at a customer site.

22. The system for the end-to-end digital transmission of a video signal of claim 18 wherein said packets are TCP/IP packets.

23. The system for the end-to-end digital transmission of a video signal of claim 18 wherein said data network is an MPLS network and said first and second routers and first and second label edge routers, respectively.

24. The system for the end-to-end digital transmission of a video signal of claim 23 wherein said MPLS network is a fiber network.

25. A system for preparing an HD signal for transmission over a data network comprising: an encoder for compressing an HD signal at a first data rate to an SD data stream at a second data rate; a video gateway in communication with said encoder to receive said SD data stream, wherein said SD data stream is configured by said video gateway into packets output through a gateway network connection; and a router in communication with said gateway network connection to receive said packets and transmit said packets over a data network.

26. The system for preparing an HD signal for transmission over a data network of claim 25 wherein said encoder is remote from said video gateway, the system further comprising: a first converter in communication with said encoder for converting said SD data stream to an optical signal; a second converter in communication with said video gateway for converting said optical signal back to said SD data stream; and an optical fiber connecting said first and second converters to carry said optical signal from said first converter to said second converter.

27. The system for preparing an HD signal for transmission over a data network of claim 25 wherein said encoder is remote from said video gateway, the system further comprising a 270 Mbps loop communicating said SD data stream from said encoder to said video gateway.

28. The system for preparing an HD signal for transmission over a data network of claim 25 wherein said encoder is remote from said video gateway, the system further comprising: a first converter in communication with said encoder for converting said SD data stream to an optical signal; a second converter in communication with said video gateway for converting said optical signal back to said SD data stream; an optical fiber connecting said first and second converters to carry said optical signal from said first converter to said second converter; and a 270 Mbps loop for communicating said SDI data stream from said second converter to said video gateway.

29. A system for preparing a plurality of HD signals for transmission over a data network, the plurality of HD signals originating from a plurality of venues, the system comprising: a plurality of encoders for compressing said plurality of HD signals into a corresponding plurality of SDI data streams, each encoder being associated with one of venue of said plurality of venues; a plurality of local digital loops, each local digital loop being in communication with a corresponding encoder of said plurality of encoders for carrying the SDI data stream of said corresponding encoder; an SDI switch having a plurality of SDI inputs in communication with said plurality of encoders through said plurality of local digital loops, said SDI switch having an SDI output for selectively outputting an individual SDI data stream selected from said plurality of SDI data streams; a video gateway in communication with said SDI switch to receive said individual SDI data stream, wherein said individual SDI data stream is configured by said video gateway into data packets output through a gateway network connection; and a router in communication with said gateway network connection to receive said data packets and retransmit said data packet over a data network.

30. The system for preparing a plurality of HD signals for transmission over a data network of claim 29 wherein said data network is an MPLS network and said router is a label edge router.