The Past, Present and Future of Delivery and Applications

Telecommunications in Transition

Neolithic cave paintings to Multi-purpose global-network terminals, humankind continues to evolve a symbiotic Logos (from the ancient Greek's smokey database of all human knowledge- not, however ironically apropos, little corporate symbols). As our technology advances, so evolves our capacity for high quality image generation, transmission, and reception.

The moving image, combined with synchronized sound is the state of the art definition of Earth culture. That is to say, "television is the most widespread form of communication in the world" (encarta.msn.com). Any study of telecommunications will be invalid should it neglect an in-depth review of past, present and future of the moving image. Towards the purpose of focused discourse, this essay will not cover the photochemical techniques of imaging associated with celluloid (the first still and moving pictures). We will start with, and concern ourselves primarily throughout- with the photoelectric methods of capturing images, and subsequent electrical (or electromagnetic) transmission of them.

TV works on a very simple fundamental concept (and yet deep understanding of the electrical engineering and physics is nearly unattainable). This process is scanning. An image is broken into perpendicular horizontal lines. Each line is broken into an individual dot of varying luminance (and in the case of color TV each dot is in turn broken into a red green and blue dot set [chrominance])

The camera is an example of a transducer. Transduction can be a very slippery opponent to grapple with when wrestling an understanding of telecommunications. In short, a transducer converts information (synonymous in this case with energy) from one form to another e.g. a camera converts the photons that make up visual light into a stream of electricity, a monitor converts a stream of electricity into photons our eyes can discern.

The camera scans the image that passes through the lens line by line, dot by dot- at a very rapid rate. Photoelectric sensors evaluate the light intensity at each point in the image and convert this information into a fluctuating stream of electricity. In the case of most cameras, camcorders and personal VHS or hi-8 recorders, the electrical stream is printed on a magnetic tape.

Whether the video signal is being transmitted live, or played from a recording- it must move from the camera, or a playback device, to a monitor so it can be viewed (transmission is a major focus later in the essay). The monitor can be a television set, a computer terminal, or even a custom closed circuit display. Most monitors are cathode-ray tubes (except for liquid crystal display, a newer technology used almost exclusively in laptops, watches and calculators- often considered inadequate due to less vivid colors and slower refresh rate).

The cathode-ray tube relies on a scanning process in reverse of the cameras. The cathode ray is actually a stream of electrons that play upon a phosphorescent stratum behind the screen. The stream traces each dot of each line over and over again. The beams is shifted by applying cyclic electromagnetic pressure as its intensity fluctuates in accordance with the received electrical broadcast (coordination of broadcast determined beam intensity, with the beams rapid cycle over the screen is one essential result of standards). Broadcast quality television is usually 640x480 dots refreshed at a rate of almost 30 times per second. The varying intensity of each dot (or pixel) is determined by the strength of the electron stream, which in turn is determined by the electrical signal being transmitted.

The transmission of analog video signals varies from application to application. The oldest and most widespread form of transmission is over electromagnetic waves. Other methods include cable connections (including cables routed from a local dish) and satellite. The electromagnetic spectrum was first used to transmit radio waves (at a lower frequency then TV- though often the term radio-waves is used to describe all communications wavelengths in the EM spectrum). The amount of EM spectrum that can be used to broadcast is finite. Slices of EM bandwidth (The information-carrying capacity of an analog EM signal is one bit/sec per Hz. So, a 1 MHz electromagnetic signal can carry one million bits per second) are granted by the government agency known as the FCC (Federal Communications Commission).

Today we define the EM spectrum (in order of increasing wavelength) by type of signal: long radio waves, AM, FM, UHF, VHF, microwaves, radar, infrared, visible light (only a small percentage of the quantifiable spectrum), ultraviolet, X-rays, and Gamma rays. Most analog TV broadcasters use the 8-VSB modulation, a method of binding the TV signal to the EM carrier waves and transmitting it terrestrially. There are options besides terrestrial broadband transmission. Cable TV started because there are several places in the US where the electromagnetic carrier waves distributed by broadcasters couldn't reach. The residents of these areas were not buying television sets. To overcome the no signal problem and generate television set sales, entrepreneurs began setting up antennas at nearby locations where the broadcast signal was clear. They would run cable from those antennas to the local homes. It was not until the 1970's that larger companies began buying out the mom and pop groups and distributing the value added broadcasts we associate with cable today.

Satellites were first used simply to bounce radio waves off of. Today Satellites have very sophisticated amplification and transmission equipment. With satellites we can bounce data around the globe in fractions of a second. Nearly all the long distance operators rely on the space bounce for connecting their disparate clientele. There is an interesting trend made possible by beaming coded messages down from satellites, or even sending them across cables. The transmission must be decoded, or unscrambled by a piece of hardware on the subscriber's end. The ease of access to these coded signals has led to a proliferation of broadcast piracy. You may be able to get a homemade signal interpreter that will give you access to hundreds of channels for the price of the official box's first six months of use.

One very simple solution to a bandwidth problem that is the largest hurdle en-route to the information age, is a conversion to digital broadcasting. Transmitting the same TV data digitally reduces its stream to less then one-tenth the size and improves the quality. Currently satellites are the only system that delivers video digitally. The switch from analog to digital TV (DTV) is inevitable. The DTV initiative is at the heart of the evolving high-definition digital TV (HDTV at more then twice the resolution of today's standard and with CD quality sound) standards.

Unlike analog video, the digital signal (due to its mathematical nature) can be compressed. This opens a wide range of options for transmitting digitally. Until recently however, most broadcast quality digital video transmissions were prohibitively large for use on existing non-TV networks. Recently however new compression methods such as ADV from Analog Devices can generate loss-less (no perceived degradation) 4:1 compression suitable for the highest quality studio applications. The ADV (ADV601LC) makes even PCs configured for budget minded consumers suitable for video production. 25 minutes of VHS quality video can be compressed to fit in 1 gigabyte of space (the currently popular MPEG2 requires almost twice as much space. MPEG2 is used for digital satellite broadcasts- as such; this new improvement in compression almost doubles the available bandwidth).

By moving from analog to digital, television service providers face challenges such as increasing network management costs, adhering to FCC guidelines, and providing their customers with high speed access services. Despite these impediments, nearly all the top hardware manufactures are devoting considerable effort to the creation of a new generation of servers that will be particularly suited to route a digital video signal. nCUBE's video server in conjunction with NextLevel's network system will enable cable operators to provide near-video-on-demand (NVOD). Currently services like Pay Per View offer a NVOD service. The PPV service is limited by several factors: short list of available movies, infrequent start times, no VCR like control. The new NVOD servers can deliver more titles more frequently (once every 15min) and offer some interactive VCR functionality (like pause). The new nCUBE servers are configurable to deliver up to 20,000 broadcast quality video streams from a single system. Oracle (who provided software to nCUBE) corporation is well invested in the initiative to provide servers for VOD, music on demand, home banking, Information on demand (IOD), et al.

The only widespread version of digital TV services is from satellite providers. Satellites have enough bandwidth not only for high DTV- they can send streams of data bits (representing any type of information and interface) alongside the contemporary broadcast. This facilitates the new breed of cross platform content simulcasts that are a significant benchmark towards truly interactive TV.

There are several possibilities on the horizon for high-bandwidth transmission methods. The first is broadband wireless, especially after the switch to fully digital data types. Along with cable modems and the capacity for T1 (1.5 Mb) to the home, are the new breed of (as yet experimental in efforts to reduce the cost of DCE equipment) X-DSLs that can deliver with very large bandwidth. Of course there is fiber optic cable, capable of huge awe-inspiring downloads and data transfers. Currently however it seems as though the wireless technologies are better poised then any other to deliver not only DTV but also interactive multimedia. There is an issue that will come further into the public eye then it has concerning satellites. In the end of 1999 there will be another occurrence of the Leonid meteor shower (every 33 years). The last time Earth passed through the trail of this particular comet (the cause of meteor showers) it was called the end of the world. The Leonid shower at the end of the 19th century is cited as one of the most epic events in earth's history by virtue of the non-stop shooting stars. In 1966 the last time our upper atmosphere was saturated with these grain-sized bits of plasma, we had hardly any communications satellites. This time around things will be quite different. Chance of a satellite being hit (any hit at those speeds with a foreign object will destroy) by orbital debris will increase by 10,000 percent. Granted the chances of a satellite going out will be still be less then one in a hundred, the threat from orbital debris will only increase as the years go by.

There are a huge variety of educational applications for digital video and it's projected hyper-components. "The national importance of improving education is well recognized" (Elton). Education's universal appeal to politicians and community members alike makes it a strong pitching point for new media peddlers. To often though, we find a specific educational test program coming under fire for not living up to its hype. This is an unfortunate result of the step by step method any society must employ to advance itself.

We must keep the primary objective of Trans-media IOD clearly in mind when criticizing efforts to broaden the spectrum (no pun) of interactive broadcast educational applications. The objective is synonymous with the phrase itself- information on demand. An intuitive customizable interface for up-to-the-minute answers to any imaginable question. Ultimately, what could possibly be more educational then access to an evolving database of all the world's knowledge? Clearly there would be resources that offered specific lessons and courses of study. Likewise we will probably see a significant increase in online help and tutoring provided by individuals and brokered by agencies.

The bottom line concerning educational applications of digital video and new media in general is: any advance in the technology that can make more information easier to access will improve public access to information and thus, education. Education can be included as a main facet of IOD and as such is essentially the backbone justification of all general expenditures that improve and add functionality to the network.

There have been experiments with the incorporation of non-video data into the broadcast signal for many years. Videotex may have failed to grab a significant consumer market in the US, however- all the new steps being taken towards merging online content with television are simply videotex with a new flavor.

Intel and Microsoft have developed new standards for delivering hyper-information (web pages, etc.) in the vertical blanking interval (VBI padding in the signal). The added informational and interactive depth can then be accessed with desktop or TV set-top applications.

NBC, CNBC, MTV, VH1, CNN, UPN, USA, QVC and other broadcast networks are all coordinating synchronized TV and online content. NBC offers NBA simulcasts that link to almost any type of information from the particular game and it's players to season travel, ticket and stadium information. This is just one example of successful integration of video streams and hyper-media. This new hybrid is neither TV, nor the Internet.

Microsoft is calling for use of the IP multicast protocol (currently in use for high-bandwidth Intranet apps) as the standard in digital broadcasting. This is being met with some resistance by the cable companies who want to maintain the half-duplex closed circuit mode of broadband wireless broadcast. In fact Intel just recently complied with the broadcasters wish that new chips for receiving TV through the PC work on a broader standard set then Microsoft was proposing. Many of the Cable Co.'s, even TCI (who seems on the verge of a $3 billion deal with Microsoft and Intel to design set-top-boxes) are committed to keeping proprietary hooks (like Microsoft's windows) out of any interactive DTV initiatives.

The Intercast Industry Group is an alliance of the big money interests from the television, PC and software industries. Their goal is unified standards for delivering typical world wide web content (including live streams like stock tickers, sports scores, weather and schedules) with TV signals. Use of VHF and UHF spectrum for delivery of content besides TV has been proven by companies like En Technology that makes components that enable the delivery of software over TV signals (recent demonstrations showed the system delivers a 10mb file in less then a minute).

Intercast uses the extra space provided by VBI and along with synchronized online distribution. It will provide a coherent merger of packet switched web content and broadcast high-bandwidth transmissions. The DTE hardware can be either a TV with a set-top box for connectivity with the packet switched network- or a PC with a tuner card for the inclusion of streaming (often analog) broadcasts into same environment as the video editing software, word processor, e-messaging and system clock.

Microsoft and DirecTV(received in 1.3 million US homes with a 30-megabit slice of satellite bandwidth) are teaming up on PC's expected early next year. The new windows environment includes the capacity to integrate a broadcast video signal with the desktop. These computers will be shipped with hardware that includes cards that work with DirecTV home dishes to receive DirecTV broadcasts of 175 channels as well as enhanced data services that complement existing online content. The all-digital system will support high quality sound and laserdisc quality video. The system is not intended to replace other high-bandwidth technologies- it is designed position the PC as a home appliance that's always turned on.

We may begin to see broadcasting as an interesting supplement to IP. While DirecTV is a one way non-interactive network, developers may choose to build interactive applications that use conventional DCE equipment (like modems, cable modems or set-top-boxes) to send feedback and interactive requests upstream to the broadcaster's hub.

Web pages synched with TV shows and sent along analog signals may evolve into the digital broadband communications network of which producers and consumers have been sci-fi dreaming. A question now becomes; which will lead the market- TVs with set-top-boxes, or PCs with tuner cards (the idea of a network computer will never gain much initiative now that we can just get the network box for the PC)? It can be argued that TVs with boxes are much cheaper, however- will HDTVs be that much cheaper then low end PCs?

The videophone may not seem particularly poised to sweep into the mainstream, however, the new advances being made in fast packet switching and circuit switch emulation may well re-introduce videophone as the final step towards fully integrating the multi-purpose global-network terminal (MPGNT). With large-bandwidth providers ramping up their resources to provide high data-rates to the home- it wont be long before a C-U/C-ME application allows integration of live video links between multiple sources. In a layered operating system the number of different windows, each with independent video feeds (and resolutions) will be limited only by bandwidth, RAM and processing speed.

Microsoft Chief Bill Gates is doing everything in his power (and his clout is considerable) to get advanced multimedia IP networks up and content-copious ASAP. The vision in Redmond is of commonplace "Gateway Destination-style PC's". This is very nearly the same thing as a MPGNT.

Ubiquitous MPGNT in conjunction with the advance of smart cards leads ultimately towards using chip cards to log into the GN. You will start each session from the customized jump point of your net ID. This initial page will contain whatever information you reference most and presumably, links to your favorite network resources. All finance will be coordinated electronically and any purchases you make online (every purchase since retailers will simply have terminals rather then registers- items ranging from adult entertainment, furniture and applications to food at a local restaurant) will instantly be credited to your account. Likewise we will very likely see a dramatic increase in freelance work by telecommuters (most of whom learned the digital design and production tasks from online resources) all of whom will be paid through a direct deposit to their network account.

The biggest issue in e-commerce, that of security and identity will be handled entirely by the ID/purchase/password card. Most public terminals will be the same, but those with accounts in higher standing will obviously get a lot more out of them. The latest episode of your favorite soap, a videoconference with your mom, and a notepad planner all in the same interface. The future of all network apps, TV, internet, telephone, is unification- and it's not far off.