其實，internet 傳真比用internet打電話發展的還早，老早就有了，是目前在internet上最賺錢的服務之一。為什麼呢?因為傳真沒有連續性的考慮。在技術上，沒有在internet 打電話複雜。你開了傳真機,一下快一下慢，這並沒什麼關係，它可以等所有的資料都到齊了再印。

不過當然如果將來Voice越來越普及的話必然是會超過Fax的，因為打電話的人畢竟還是比傳真的人多，那還有就是將來在InterNet上是否可以Video的東西，其實在十幾二十年前，在各位出生之前，AT&T已經研究出影像電話的產品出來了，打電話的同時有個小螢光幕可以看到對方，但是一直不能普及，其實這應該跟人性有關吧，只是打電話只要聲音的溝通就好了，我不用讓你看得到嘛，如果真的需要面對面的接觸，請你作特別的安排，所以影像電話的實用性並不是那麼高，不過開會就可能需要了，比如說我要給你看一個圖表或設計圖，用口頭上的言語絕對不及圖表的直接說明，還有比如說講地址，如果雙方都有地圖在手講起來比較不容易有誤差，如果單就口語溝通這個誤解就很容易產生了，不難看出Video的功能是在於較複雜的描述時才會需要的。

以後網路電話會非常人性化，功能也十分彈性，也很容易設定，因為它是由電腦起家的，它可以有很友善的GUI介面，例如轉接服務甚至可以設定的很精密
 

電通所相關計畫介紹

麼叫做I-Phone呢？就是PC啊！就是你在傳統電話裡裝一個小PC，裡面有Modem，直接走Hinet或Seednet，你也可以用來傳Fax，這些是屬於使用者端。系統端呢，就是剛剛講的Gateway，Gateway還可以分為企業，IPST用的,Internet PBS 等等FAx Server 像你傳真你不是直接傳到對岸，你是先傳到Server, Server 再替你送到目的地所以它並不是real time，但現在正在發展一些real time更新的技術。

CTI的技術稍微講一下，我們在辦公室的桌上有兩項設備，一個是電話，一個是電腦。傳統這兩個是不同的世界分別連到不同的網路。通常一個提供服務的人員，電話打進來就問：請問你的帳號是什麼，你就輸入電腦，就把他的資料印出來，但這種方式很浪費時間。現在是電話進來機器就自動問你的帳號是多少，資料就直接顯示在電腦上所以鈴響的時候他就已經之倒是誰打電話進來了。你也可以把資料在轉給下一個人。這不僅省客戶的時間，也省了企業主的時間這可以提升公司的營業效率。


　結論

　
        通訊你們大概還聽不大懂，民生電子主要是在電視方面，所以像有線電視網路的技術與HDTV，數位電視等等，都是電通所研究的方向。這三方面的技術就非常多，像對自動化方面，我們有提供相當多的服務，比如說工廠的自動化，辦公室的網路系統，我們最近看到一些汞污泥的事件，就是委託中研院來作檢驗，所以化工所就可以負責這一方面的問題。中研院的人出去，因為具有這一方面的知識，所以他所做的一些評鑑就蠻有公信力的。在新竹他們會把園區和中研院混在一起，其實是不太一樣的。中研院是一個研究單位，園區是一個生產製造的地方，整體來講中研院的特色是高學歷，而園區是生產量高，所以園區其實並不是高學歷，裡面大概有1/2是專科畢業生，公司的老闆也懂得要省成本，因此沒必要也不會請高學歷的人。反過來講在中研院60%以上是碩士畢業，其他是大學或專科做一些行政管理的工作，所以是不太一樣的。我們現在來講剛剛提到的三個領域:電腦、通訊及民生電子。民生電子的話，比如說setbox，就是把家裡電視機連到有線電視的網路的一個介面。現在都把這個setbox直接做到電視裡面，現在我們在做的是數位電視的setbox。現在的電視是類比式的，但是我希望用數位來傳輸，就不會有干擾及雜音。因為數位就是0和1嘛，只要能夠區別出0和1，你可以把這個訊號重整回來成一模一樣的畫面，這就是數位傳真的好處。如果用類比的話，例如聲音經過一段距離後就模糊掉了，影像也是一樣，如果是用數位處理的話，他最重要的就是保持原信號的真實度，他不會做任何的改變。在傳輸過程中0和1不要被干擾到會互換，基本上你可以把傳送出去的信號一模一樣的呈現在接收端，這就是數位傳真最主要的目的。高畫質電視叫HDTV，HDTV看起來不會很快出現，數位電視會比較先出現，就是DTV。我們傳統電視還想繼續使用的話，就需要一個setbox把數位訊號轉換為類比信號呈現在你的類比電視，數位電視明年要開播，你就要買一台新的數位電視，要不然就要裝一個數位電視轉換器。

        另外呢，現在電腦已經不是單機作業了，都是在網路上彼此連在一起，事實上叫做分散式運算。你要做事情不要說只靠一台，可以說我把資料送給一個功能比較強大的server去做，算完後把結果丟還給我就可以了，我不必說在自己的電腦裡算了半天。分散式的運算有很多的技術，譬如說你的database分散，你的運算分散，第三你的整個網路環境當成一個大電腦，一個任務來得時候可以分配給其他電腦，至於由誰來操縱，就是有一個distribute OS，它可以把很多電腦整合成一個大電腦，所以工作執行到一半可以換給另一台電腦執行。這當然是一個很理想的情況，這技術目前還不是很成熟。現在事實上已經整合在一起，不太能區分這三個領域分成電腦類，通訊類及民生電子類，因為都有關係。民生電子也有網路和通訊，剛剛講電腦在網路上分散，他也是通訊啊。

網際網路電信這個產業，假如公司在台北，分公司在新竹，那我們打電話時，每一個公司都會有一個企業交換機---PBX，傳統上，電話是一個網路，比如說學校，假使政大有一個分部在汐止，總部校區有一個 PBX，學校裡面那就不必每一個電話都拉專線到中華電信，而只要共用一個主機，假設學校總共有50台電話，如果我們拉一條T1可支援24條電話線，那50台電話可以共享24條電話線，因為也不可能同時50台電話都在使用，只要平均下來有24個人同時使用，那一條T1 就可以了。因此，就不需要付50條專線的電話費，只 須支付一條T1的費用，內線不用錢，可以有50條，但外線要錢，所以一條T1使用，所以每一個企業或團體都使用PBX，先集合起來再把電話轉出去，外線內線的比例通常達到1比10。因為我們發現通常都是內部對打比較多，打出去的比較少。
          接下來是我們今天的主題----網際網路電信這個產業，新竹打到台北傳統電話打的路線付的是長途電話費，就比是內電話貴得多，假使今天可以走INTERNET或INTRANET，讓我在台北及新竹間拉一條專線，雖然傳統是用來傳DATA，但是我們可以用來傳聲音，可能使用者在打出去經過PBX時，可以讓使用者選擇走傳統的電話線或是INTERNET。像是打給客戶就使用外線走internet，至於打給同事就可以選擇打內線了，大概是這樣。現在我們事實上的ISP(Internet Service Provider)，像seednet，hinet就是ISP，seednet，hinet目前還沒有提供電話的服務，它只提供上網的服務，今天你要伸請然後它會給你一個帳號和password，然後你用modem撥電話上去，然後上網，它依照使用量然後按月收費，這是ISP。但是今日如果ISP提供電話的服務那它就成了ITSP(Internet Telephone Service Provider)，使用者就不一定透過modem，而只是打電話連上當地的ISP的電話機，然後電話機將電話轉換成封包，將聲音轉成一個一個的封包，然後照順序傳過去，通過internet，在一個一個轉回來，所以使用這種方式的話，就算從台北到新竹，我算是打市內電話，然後用網路到新竹，5分鐘1.7元，就算上網的費用照月收，也比較划算，除了gateway還有一個像net server的機制，能夠區別電話，從區號就能知道你要傳到那，像04就是要到台中，那你就不必先經過新竹，也就是要能江電話號碼轉為IP address，在網路上知道要將封包傳到那，傳到後，在將IP address轉為電話號碼知到要打到那，這都是要有管理的，不是只是將電話轉為封包這麼簡單。這是大概講一下如何在internet上打電話。
 

所以，其實不是那麼簡單，把聲音裝成封包出去，你還要告訴它目的地在那裡、ip address和電話號碼之間要如何轉換，這是在說明如何用internet來做電信。那VOIP的市場到底多大呢?其實市場大囉。VOIP，就是voice over TCP/IP。TCP/IP，事實上，就是指資訊網路。在美國市場中，長途電話和國際電話是不一樣的，長途是指在美國國內，指的是跨州、或是跨區域號碼。如，從408打到415，美國的區域號碼，area code，都是三碼，也許是在同一州，但區域號碼不一樣，所以還是算長途。就像，台北到基隆，都是02，所以兩者間是屬於市內電話，至於台北打到桃園，也許比到基隆近，但由於跨了一個區碼，所以，是從02到03，所以是算長途。雖然，台北打到基隆較遠，但是，屬於同一區碼02，所以，是五分鐘一塊七。台北打到桃園比較近，但跨碼，所以，一分鐘要好幾塊。以上講的是長途電話。

國際電話，是從美國打到外國，如從美國打到加拿大、日本、台灣、歐洲。國際電話當然是比較貴。如果它使用VOIP，用網際網路來打電話，將來在國際電話領域一定會有很大的市場在。因為國際電話非常貴，這裡指的是使用傳統的長途電話機。所以，大家會更希望走internet來打國際電話。至於，長途電話也是一樣的，因為長途也算是比較貴的。那有沒有人說要以internet來打市內電話。沒有必要嘛，五分鐘一塊七，你何必走internet呢，反而貴耶。需要三塊四，因為你有兩端，上網和下網各一次，算兩通電話。所以，同一個區碼，沒人會用VOIP。如，台北到基隆屬於同一區，千萬不要上網，上網，費用加倍;不上網，不但話質清晰，而且便宜。所以，同一區碼不要上網，不要走internet，使用VOIP，只有在跨區碼時才划算。所以，它為什麼是指長途、國際電話，原因即是在此。市內電話，當然沒有人會去用VOIP。至於，長途和國際的市場，VOIP當然會成長，因為它能減少通話費用。其中，當然也要靠電信公司的政策，如果它發現你走internet打電話價錢會降低，它為了要競爭，它也會把價錢降低，因此，也許轉去使用VOIP的人就會減少。但以目前的收費價位而言，大家還是希望使用VOIP。

那使用internet來打電話的比率會有多大的變化呢?這裡指的是長途電話，因為市內電話，沒有人會去使用internet ，所以我們只講長途電話。長途電話long distance和國際電話international是不一樣的，如在台灣，長途是指不同縣市之間。至於，離開台灣就是國際電話，如到日本、美國、大陸。在美國，由於美國比較先進，所以使用者的觀念比較新，所以，他們知道使用VOIP的好處，也因此使用比率比較高。以VOIP的使用比率來看，大概從1998到2003之間，會有7%的長途電話會使用VOIP，預估到2003的話，會有26%。這裡的比率它是以時間來計算，也就是每四分鐘中有一分鐘是使用VOIP。那為何預估的會有兩條曲線呢?一個是樂觀，另外是悲觀的預估。其中悲觀只有樂觀的一半，也就是13%。就是算是13%的話，那也有八分之一。所以，大概有八分之一到四分之一的人在2003年時會使用VOIP，而VOIP目前也一直在進步、改進中，所以，將來在品質上會越來越好。

傳統的電信網路，PSTN，packet switch telephone network，它的通話時間，conversation minute，是以十億分鐘為單位。雖然，VOIP的使用越來越多，但並不代表傳統網路會大量減少，它還是會繼續增加。按照這個預測表，在2001到2003之間，傳統網路才會開始減少，因為，VOIP那時會變的大量被使用。在2001和2002間，VOIP的技術會改善到非常好，所以一般人會樂於使用。至於，現在為何那麼少呢，因為現在的通話的品質還不是非常好。所以，以internet來打電話，目前品質還是相當差，而只有學生、或實驗者才會使用internet來打電話。但這些，都是實驗、或好玩而已。在將來，VOIP品質會越來越好，大家就會覺得沒啥不可，進而轉而使用VOIP。不過，品質越好，但，相對的，成本會越來越高。另外，傳統的電信業者，為了和VOIP競爭，也會降價，所以，後來會呈現勢均力敵的態勢。可能VOIP和傳統電信網路在價格上會差不多。但由於傳統電話大家都已經有一支了，所以，並不是每個人都會換到VOIP。在VOIP的使用者中，有一部分的人是從傳統電話轉成使用VOIP的，而另一部分是沒有關掉原來電話，而另外牽一條線使用VOIP的。所以，VOIP的使用者是把兩者加起來的。這才是總共的VOIP電話量。在2005年時，VOIP可以占到使用率的一半，也就是五百billion 中的兩百五十billion。所以，你可以看到growth rate of annual，每年的成長率，傳統電話大概是3.2，其實後來是下降的。而VOIP是每年超過一倍成長的。

現在要講的是gateway，為什麼會覺得gateway很重要呢?傳統講I-phone、internet-phone，都是講我們在電腦前面，裝著microphone、喇叭來使用，因此，非常不方便。而對我們使用電話而言，都是拿起電話就使用。不可能說，你要打電話，還跑到電腦前開機，等到開機完成後，我想，搞不好你都已經忘記你要講什麼，甚至連你要打給誰都忘了。所以，這些是非常不人性化的。也就是說，透過電腦來打電話，所謂的I-phone，是不會成功的，只有少數學者、研究人員它用來做研究。只有讓它變得很好用，也就是我們打電話還是到桌上抓電話機，拿起來就打，這樣才可能被大眾所接受。我們知道我們用的還是傳統電話機，並沒有電腦在裡面，那它怎樣才能上網路呢?其中用的就是gateway。我們用的是電話，就像你辦公室、家裡、學校的電話，接通後，先會被連到PTN，也就是你企業大樓的總機，那時它才會問你要走傳統的電話網路(長途電話網路)，還是internet。若你說你不在乎品質，那就它就會走internet 。反之，你說你這是個重要電話，不能斷斷續續，那它就會走傳統的電話網路。所以，這些都是gateway在負責。也因此，gateway變得是真正重要的產品。至於，I-phone，所謂用電腦打電話(把軟體裝在電腦，然後加上額外所需的配件，電腦就可以打電話)那種東西反而沒有什麼用，需求量不會很大，真正量大的是gateway。你看，gateway全球的市場，到2002年是31億美元，1000億台幣耶。所以，各位如果想創業的話，gateway是很好的一種選擇。

所以，對美國人來說，在網路上傳真，是可以省很多錢的。因為，他只需付local的固定電話費，也就等於市內電話是免費的。由紐約傳真到舊金山，isp從internet接到由紐約傳來的資料，再送到你指定的目的地時，這段也是不用錢的。因為對isp而言，那也只是付固定的月租費而已。加上中間是走internet，也是不用錢。所以，由紐約在舊金山這整條路線好像都是不用錢。提供這服務的人，他只要收你五塊錢，他大概就賺了五塊錢，中間他大概不需要負擔到費用。所以變成好像是整條路線都不要錢一樣，提供這項服務的人他們只要收你五塊錢就是實收五塊錢，等於是InterNet的額外收入，因此InterNet上的Fax可以節省個人用戶及企業很多花費，所以如果我要傳真，我就傳給我的ISP如HINET或SEEDNET，而它們自然會把傳真傳到目的地，它不但能減少收費而且東西一樣傳得到，因此這種服務的營業額其實是比Voice還要來得大很多。

不過當然如果將來Voice越來越普及的話必然是會超過Fax的，因為打電話的人畢竟還是比傳真的人多，那還有就是將來在InterNet上是否可以Video的東西，其實在十幾二十年前，在各位出生之前，AT&T已經研究出影像電話的產品出來了，打電話的同時有個小螢光幕可以看到對方，但是一直不能普及，其實這應該跟人性有關吧，只是打電話只要聲音的溝通就好了，我不用讓你看得到嘛，如果真的需要面對面的接觸，請你作特別的安排，所以影像電話的實用性並不是那麼高，不過開會就可能需要了，比如說我要給你看一個圖表或設計圖，用口頭上的言語絕對不及圖表的直接說明，還有比如說講地址，如果雙方都有地圖在手講起來比較不容易有誤差，如果單就口語溝通這個誤解就很容易產生了，不難看出Video的功能是在於較複雜的描述時才會需要的，但是簡單溝通基本上用講話就可以了，所以我們可以說人跟人的溝通90%用語言就可以了，不過有那10%是需要影像了，而這就是影像電話的發揮機會了，但大至說起來Video的用途還是比較有限的，那因為我們是做Voice的研究，基本上學術界都喜歡走高科技的路線，最好是我這樣技術可以包含所有的功能，因此他們一定會把Video的東西放進去，把多媒體的東西包括語音還有影像以及資料都放了進去，最後的結果是產品貴得不得了，因為影像是很難處理的東西，卻又沒有太大的用處，影像處理把系統成本大大提高，而運算速度卻大大的降低，因為要計算連續動畫或者是影片處理，幾乎所有的CPU都拿來做這些事情，那VOICE跟DATA部份就分不到太多了的資源，所以處理起來就比較慢了，結果VIDEO的部份又是最沒有人要用的，所以很多系統如果加了VIDEO之後反而變成畫蛇添足，把VIDEO拿掉的話，第一節省頻寬，因為影像的東西頻寬耗損非常的大，一張圖片要1024*500個點，每一個點要3個BYTE，這樣算起來一張圖就要1.5MegaByte，就是要12MegaBit，這是一張圖而已，電腦螢光幕每秒要30張圖，也就是要360MegaBit Per Second，這當然不可行啊，所以一定要壓縮，壓個一兩百倍了不起吧，壓下去跟解出來都已經不太一樣了啦，就算是壓200倍好了，也是要1.8MegaBit Per Second，一條T1的線都還不夠，由此就可以知道VIDEO的量是非常可觀的，它使用掉很多電腦的頻寬，也使用掉很多電腦的能力，但是它的效果卻很有限，所以在處理系統的時候一定要將它們分開，如果這個系統是專門處理語音，就不要牽涉到影像部份，因為我去國外參加過許多次國際的會議，我看過有很多公司就是碰到VIDEO之後就破產了，它們做出來的東西雖然有VIDEO在裡面，但是價格是別人的五倍甚至十倍，就算只是三倍，大家都覺得我不需要影像啊，我只要聲音就好啦，所以產品銷路都不太好，所以以前很多被騙去做VIDEO的研究室都關門大吉了，因為公司投資了之後發現，產品的銷量並沒有起來，它的投資都沒辦法回收，根本沒有多少人買，最後的結果都是部門被裁減，嚴重的就關掉了，現在只剩下那種很大的電話公司，反正它的資產雄厚、不怕虧損，但是這些研究人員都很挫折，他們花了心血做出東西來，卻都沒有人要用，因為消費者不喜歡講電話還要讓你看到我，如果90%都是把螢幕關掉的，那我又何必買呢？更何況又不是很便宜的東西，所以大家也逐漸認知到VIDEO千萬不要隨便放到系統裡面來，一放進去系統就失敗，把VIDEO拿掉系統就成功，因為系統就變得又快又便宜，而且可以專心把語音、資料的部份做好，現在有幾個方面。

『語音應用』是只做語音連資料都不處理，不要把每一樣都攬進來，最後卻沒有一樣做的好，專心把語音做好再把價格壓低，這樣才有市場也才有競爭力；『資料處理』在網路上可以交談，要是即時，也是一個不錯的方向。最重要的就是『VOIP』，利用那網際網路電信的特性，就是做便宜的長途電話，這也就是當初開始的原因，幾乎可以節省80%的電話費，不過現在有一個變數，就是在美國有電信公司抗議認為這樣不公平，為什麼電信公司的監理如此嚴格，價格的調整也受到限制，還要繳額外的稅，走Internet打電話的人就完全都不受管制，品質、價格都自由化，這樣相當不公平，這應該也要列入管制的範圍，一旦列入監管『VOIP』的成本就勢必要提高，可能就要繳某個程度的稅額，而且在費率上可能也不能如此隨心所欲了，也要付費可那些替它接續的長途電話公司及區域電話公司，『VOIP』被國家管制之後成本一定會提高，原本可以節省到80%的可能只能省到40%到50%了，萬一電話公司再一狠心也降價競爭，那價格上的優勢可能就不那麼明顯了。

那時就是功能上的競爭了，以後網路電話會非常人性化，功能也十分彈性，也很容易設定，因為它是由電腦起家的，它可以有很友善的GUI介面，例如轉接服務甚至可以設定的很精密，幾點到幾點請轉到哪裡，下班後請轉接到我家，沒有人請轉到我的大哥大，太晚了請不要響，都可以很彈性的設定，不會像現在的電話非常難設定而且功能有限，所以以後網路電話最大的賣點是它的功能非常的活潑且具彈性，這可能是傳統電信服務所沒辦法比的。

不過目前網路電話還是沒辦法普及，因為它的速度跟品質還是無法達到可讓人接受的程度，最主要還是因為頻寬上的問題，將來網路電話業者如果真的要認真來經營的話，它絕對不能把資料就把它往網路上一丟，讓它自己到目的地去，它如果想要做出好的品質的話，一定要有一個良好控制的系統，可以把封包抵達的延遲縮小到可以忍受的範圍之內，譬如說它在幾個大城市都有一個專門的接收點，這些接收點的接收點都是有即時功能，而這個網路是跟我們一般使用的Internet是分開的，是它為網路電話所建的一個專屬網路，在這上面是語音優先，因為語言的延遲如果超過0.3秒，話是講不下去的，不信的話可以試試打長途到美國去，如果延遲超過0.3秒，你一講完沒聽到對方的回應，馬上再講，結果對方才聽到你說的準備回答，你的第二句話就來了，就碰在一塊了，因為語音的延遲是有意義的，是沒辦法隨便改的，所以語音的連續性很重要，很簡單就講我跟你借錢，假設我用網路電話跟連主任借錢，譬如說我跟他借參萬塊，我們一連上，我就說「連主任啊，最近手頭緊想跟你借個參萬塊。」我講完這句話剛好網路塞車，過了兩秒鐘連主任才聽到這句話，他就立刻回答說「沒問題啊！」可是因為網路塞車我過了三秒鐘才聽到他的回答，雖然他是聽到就回答，可是我隔了三秒鐘才聽到，事實上三秒是很久的啊，我會認為奇怪，只是借的三萬塊還要想那麼久，那就算了吧，這樣就造成誤會了。事實上，人的語言裡「停頓」是有意義的，如果你跟一個人說明一件事的時候，你發現他都沒有講話，那個感覺會覺得說你是不是沒聽懂，你會再補充，那會發現你就一直講下去，對方會覺得不知道什麼時候才可以插嘴，那就變成沒辦法溝通了。『VOIP』最大的問題就是「延遲」沒辦法控制，現在的問題是，因為聲音上上網路一定要先變成DATA，所以就要先壓縮成數位信號，才不會佔太大的頻寬再送到遠端，收到後再解壓後數位轉類比才變回聲音，光是這樣一趟就要0.15秒了，來回就是0.3秒的人類極限了，目前大部份的網路電話系統都是超過0.3秒的，所以講起來就覺得很痛苦，不過隨著電腦越來越快，這應該都可以突破的才是。產業的話有使用者端，像I－PHINE他的產業當然有CT端，就是USER使用端，像I-Phone，用PC打電話POTS（Play of telephone System ）就是傳統電話，但它裡面有I-Phone的能力。

CTI的技術稍微講一下，我們在辦公室的桌上有兩項設備，一個是電話，一個是電腦。傳統這兩個是不同的世界分別連到不同的網路。通常一個提供服務的人員，電話打進來就問：請問你的帳號是什麼，你就輸入電腦，就把他的資料印出來，但這種方式很浪費時間。現在是電話進來機器就自動問你的帳號是多少，資料就直接顯示在電腦上所以鈴響的時候他就已經之倒是誰打電話進來了。你也可以把資料在轉給下一個人。這不僅省客戶的時間，也省了企業主的時間這可以提升公司的營業效率。

Digital television presents many exciting possibilities—interactivity, data broadcasting, electronic commerce, better pictures and audio, and high definition television (HDTV). Like many concepts related to digital television, however, HDTV is itself the subject of continued debate. Read below to find out the exciting ways HDTV fits into the digital TV picture.

About Digital TV

The United States television industry is going through a profound transition: from analog to digital broadcasts. Like the transition from black and white to color TV, it will undoubtedly take years for the industry to fully make the move from analog to digital TV. As mandated in 1996 by Congress and the Federal Communications Commission (FCC), the rollout of digital TV will be a gradual one, with most U.S. television stations expected to be up and running by 2006. Although this deadline may be extended, there is a firm commitment to allow stations to broadcast both analog and digital signals during the transition process.

The increased carrying capacity of digital TV signals, along with their superior video compression capabilities, means that TV viewers will have more choices than ever before. Electronic commerce, electronic program guides, interactive TV, multiple channels within the same bandwidth, instant replay—these are just some of the possibilities digital TV will make happen. But the most anticipated—and talked about— choice in this evolving landscape is high definition television, HDTV.

About HDTV

Although standards for what constitutes HDTV have been in development for about a dozen years, no single standard has yet emerged. Instead several versions of HDTV are taking shape. While all versions promise dramatically better sound and picture quality—approaching a movie theater experience—some proposed versions of digital television would allow you to take advantage of an array of compelling applications. Among these are multiple channels within a single bandwidth, as well as interactive TV and data broadcasting (for viewing on an assortment of receivers, including current and future TV set-top boxes, broadcast-enabled computers, and handheld TV-enabled devices).

Broadcasters have already started broadcasting digital TV, including HDTV. The National Association of Broadcasters (NAB) says 42 stations, most of them within the top 10 U.S. TV markets, have already broadcast HDTV, either entire programs or test transmissions. Many more are coming soon. In May 1999, broadcasters in the top 30 U.S. markets are required by the FCC to begin offering digital broadcasts, covering almost 50 percent of U.S. television households.

The Big Picture

Digital TV signals provide crystal-clear pictures and CD-quality sound. HDTV provides the maximum benefits of the digital TV experience. The TV industry has generally accepted that HDTV begins with a resolution at least twice that of analog television. That visually stunning clarity can increase to more than six times the resolution available on today's analog TV sets.

Beyond resolution, there are other features that make HDTV a superior visual experience. Many versions of HDTV are maximized for a wide screen format with a 16-by-9 width-to-height ratio. The standard analog broadcast today employs a 4-by-3 format. The wide-screen HDTV format is similar to a movie theater experience. It essentially fills a person's entire field of view, offering a richer visual experience.

Along with the several emerging versions of HDTV, digital TV also includes standard definition TV, or SDTV. Each of these digital formats provides dramatic improvements in picture and sound quality. Viewers will be able to enjoy them by watching on a range of appliances, including 4-by-3 digital TV sets, current analog TV sets outfitted with inexpensive digital set-top boxes, and wide-screen HDTV sets. In all likelihood, the marketplace will determine how much programming will be available in the various flavors of HDTV and SDTV.

Viewers of digital TV and HDTV can also benefit from CD-quality "surround sound." This is the same Dolby Digital (AC3) standard used in movies on digital versatile discs, or DVD. This sound system can include up to 5.1 channels of sound: three in front (left, center, and right) and two in back (left and right). Not every HDTV program will automatically include this CD-quality sound. But most Hollywood movies already employ a similar audio standard and will be among the most common HDTV broadcasts utilizing this "surround superior sound."

(09/14/98, 12:11 p.m. ET)
By George Leopold, EE Times

Urged on by an Aug. 13 letter from the Federal Communications Commission, in which FCC Chairman William Kennard asked for DTV-cable compatibility, the Consumer Electronics Manufacturers Association, in Arlington, Va., asked the FCC to press cable operators to cooperate in developing a cable-ready compatibility proposal that had been issued by the FCC in late June. But as of Sept. 10, CEMA received no response from the National Cable Television Association, in Washington, D.C., to this proposal, CEMA said in its reply to Kennard.

At issue is how DTV broadcasts, which are scheduled to begin Nov. 1, will be delivered to cable subscribers. Kennard urged all sides to complete work on an IEEE 1394 digital interface between DTV receivers and cable set tops by the fall. CEMA said a standards group is working to complete the 1394 interface standard by the Nov. 1 deadline, but is also proposing three other near-term options that would provide digital interfaces between DTV receivers and other home electronics systems, including PCs, VCRs, satellite receivers, DVD players, and digital Surround Sound processors.

"These solutions must meet consumers' long-term need for cost-effective digital interfaces to DTV receivers from other consumer electronics devices found in the household," CEMA president Gary Shapiro told Kennard.

CEMA and NCTA were earlier asked by the FCC to form an advisory group to work out compatibility issues and ensure consumers had broad access to new digital equipment. Out of those deliberations emerged CEMA's proposed cable-ready digital receiver standard.

The CEMA proposal contains four different interfaces: the 1394 interface, an RF remodulator interface (published as EIA-762), a component video interface (published as EIA-770), and the National Renewable Security Standard (NRSS) interface (published as EIA-679).

The RF remodulator interface, for example, lets QAM, the cable industry's transmission modulation signal, be remodulated into vestigial sideband, the transmission standard specified for DTV, so a digital cable set-top box can be directly connected to a DTV receiver.

The component video interface is another key element of the CEMA's proposal. It gives a near-term solution for both cable set-tops and DTV sets to get connected without resorting to IEEE 1394. The component video interface has been used for many years in professional video equipment, but this is the first time the technology has been standardized for consumer electronics products. A DTV receiver set-top to be launched by Panasonic next month, for example, will be equipped with the component video interface.

The NRSS interface is crucial for digital cable-ready TV receivers. It allows a DTV receiver to use a smart card or PCMCIA card to provide access security to pay and subscription cable or satellite TV services, telephony, and all forms of e-commerce.

The CEMA argued its cable-ready proposal would let cable operators connect directly to DTV receivers, thereby eliminating set-top compatibility problems and reducing equipment costs and complexity for consumers. FCC and NCTA officials did not return phone calls Friday seeking comment on the CEMA's proposals.

NEW YORK -- The direct broadcast satellite (DBS) industry faces significant challenges to adding new subscribers as digital terrestrial television broadcasts begin this fall and as cable TV providers prepare plans to implement digital cable.

Upgrades to digital cable could allow improvements to the quality of cable services and add Internet-access, phone, and multimedia services that would create competition and possibly lure away DBS customers, analysts said.

New subscribers to satellite services may peak in 1998, and the DBS industry's window of opportunity for adding further subscribers will close soon after 2000, said Vijay Jayant, associate director in the equity research department at Bear Stearns & Co., in New York. Then it will become harder for satellite operators to compete on price and value in the mass market, Jayant said.

The Boston-based Yankee Group said it estimates digital cable could attract 1.5 million households by the end of 1998 and increase to 9 million homes by 2002.

Acknowledging the challenges ahead of them, DBS providers at the Satellite Broadcasting and Communications Association's SkyForum here in New York Monday said they are nevertheless unafraid.

Rather than stealing away potential DBS customers, DBS providers said the introduction of digital cable will generate greater interest in DBS services.

"People who aren't in the cluster markets that will be upgraded by cable early will look into satellite services as an alternative," said one satellite broadcasting executive. DBS already provides between 150 to 200 channels and a better picture than standard cable, and will replace cable for some who must wait for improved digital cable service, DBS executives said.

The fact that cable services aren't yet ready for digital TV (DTV) will help boost DBS service in the interim, said Stanley E. Hubbard, president and CEO of U.S Satellite Broadcasting Co., which provides premium movie channels.

"As digital TV rolls out, folks will receive local digital channels via antenna," said Hubbard. "This will help the [satellite] industry a lot. It will counter claims that the cable industry has made over the years saying you can't get local channels without cable."

Cable and satellite TV customers will need to use off-air antennae to receive the first digital terrestrial broadcasts scheduled to begin Nov. 1, because first-generation DTVs won't be equipped to receive digital broadcast via cable. Consumer electronics, cable, and Hollywood factions have been unable to resolve differences regarding how a set-top box is to be connected to a digital-TV receiver. It is expected that receivers will be equipped with the IEEE 1394 digital interface required to receive DTV broadcasts by 1999.

In the meantime, satellite service providers said they plan to exploit their advantages over cable. For instance, while cable providers spend time and money to build out a digital cable network, satellite services across the nation will be able to switch to digital service instantly, according to Jayant.

In addition, satellite broadcasters are moving ahead with plans for receiving terrestrial digital signals. For instance, DirecTV and U.S Satellite Broadcasting have arranged for Thomson Consumer Electronics to build a Digital Satellite System receiver into Thomson's future digital TVs to enable them to receive satellite DTV broadcasts from DirecTV and/or U.S Satellite Broadcasting along with digital terrestrial broadcasts.

Some analysts question whether it makes economic sense for satellite broadcasters to use their limited capacity to carry digital broadcasts, which hog bandwidth. Each satellite transponder is limited to 27-megabit-per-second throughput, and a High Definition TV signal is expected to use 19 Mbps, according to Jayant. So a 32-transponder satellite would have the capacity to handle 45 to 64 HDTV channels, compared with nearly 200 channels in standard definition television.

(09/20/98, 8:24 a.m. ET)
By Junko Yoshida, EE Times

LEIDSCHENDAM, Netherlands -- With a goal to integrate 2-D, 3-D, and streaming content for digital TV (DTV) programming, leaders from key international technology-development forums gathered here last week to launch a new initiative to harmonize the various multimedia streams.

Taking part in the AIC meeting were representatives from the Motion Picture Experts Group, Virtual Reality Modeling Language organization, and Advanced Television Systems Committee (ATSC). The initiative will "write an open specification to integrate and harmonize VRML, MPEG-4, and Broadcast HTML [BHTML] into a seamless stream," said Rob Glidden, co-chairman of VRML 3-D Integrated Media Working Group and one of 12 founding members of AIC.

Common Goal

To a certain degree, the new initiative shares a common objective with the Intel-led Advanced Television Enhancement Forum (ATVEF). Both aim to create a content-programming platform for a broadcast environment.

The AIC proponents, however, are going a few steps further, according to Cliff Reader, a key player in the MPEG-4 standard development and also an AIC founding member.

"While many in the industry today are thinking how they can add HTML to TV," Reader said, "our vision is how we can create a rich set of 2-D and 3-D objects, audiovisual streaming content in a broadcast environment, for which HTML -- or an application like seeing Web pages on a TV -- may be only a part."

ATSC's DTV Application Software Environment group is examining two competing proposals, one by ATVEF and the other being refined by the Broadcast HTML team within the DTV Application Software Environment group. BHTML, written in the emerging Extensible Markup Language (XML), is designed for tight integration with the Java framework.

Given that AIC lists the chairman of the DTV Application Software Environment group as well as the BHTML team leader among its founders, it's no wonder the effort is already causing a stir among ATVEF backers. (The DTV Application Software Environment group chairman is Aninda DasGupta of Philips Research; Ted Wugofski of Gateway is the BHTML team leader.)

Some said they believe the motivation is to promote BHTML, even if the ATSC doesn't wind up ratifying that technology. One executive in the ATVEF camp, who spoke on the condition of anonymity, warned, "The AIC, not being a due-process standards body, is in questionable territory if it presumes to invoke an international platform standard based on BHTML."

AIC members vigorously disagree. AIC is founded mostly by individual technical leaders of industry forums and is committed to serving as integrator of disparate standards. It is not a consortium of corporations vying to promote a proprietary spec.

"This [AIC] is not yet another forum to set a standard," said Glidden.

Pointing to longstanding integration efforts between VRML and XML, as well as between MPEG-4 and VRML, Glidden said, "This is a natural extension of what we have been doing at each of the groups."

Moreover, the initiative fills gap in work done by each group thus far. Each member is responsible for sharing any developments discussed in AIC with his original standards body. Thus, after drafting a spec, the AIC members would have to win over the appropriate bodies and get the specification approved there. "We see ourselves more as a facilitator," Glidden said.

As for BHTML, Glidden said, "Although we see BHTML as a good technical solution, we have no intention to replace the development work by the BHTML team at the DTV Application Software Environment group. Nor will our work within the AIC be dependent upon their BHTML development. We may end up finding a solution similar to BHTML, but not necessarily BHTML itself."

Getting To The Crux Of The Problem

AIC founders appear to believe the problem they must solve is fairly straightforward. Because there is no well-defined way to integrate such key technologies as VRML, MPEG-4, and BHTML, their job is to develop and specify syntax and tools for this integration. More specifically, they plan to add a BHTML stream to MPEG-4, while defining "an integration of language and interface between BHTML and VRML/Binary Format for Scenes," or BIFS, said Glidden. In his view, BIFS and VRML are dual representations of the same content, BIFS in a binary form, and VRML in a textual.

As for tools, "The use of MPEG-4 in this integration effort is a marriage made in heaven," said Reader. MPEG-4, an object-oriented data representation, uses the same tools as MPEG-2, compressed digital audio/video streams. The two share the same timing model, the same clock reference, and the same time stamps.

"All these things allow a perfect synchronization between MPEG-4's objects and DTV audio/video streams, a precisely guaranteed quality of service," Reader said. "The exact lip-sync experience of streaming can now be fused with 3-D graphics objects and VRML."

The AIC founders said they believe no new technology is needed for such an integration work. And while there may be a few ways of integrating these tools, they hope to specify just one.

The AIC initiative has already set a very tight and ambitious schedule. The group will deliver the spec by December and validate it in a working implementation by March 1999. The group set the timetable by mapping its efforts onto the concurrent time line set for the open standards processes of MPEG, VRML, and ATSC.

Noting that the dozen AIC founders are all experts in actually writing specifications in their respective standards organizations, "We set the schedule by already allocating resources from our members," said Glidden. He also promised commercial products based on the new spec can be launched in the fourth quarter of next year.

Content developed on a platform based on the newly integrated spec will be delivered by using MPEG-2 or IP transport protocols. The network infrastructure used for the delivery of integrated 2-D, 3-D, and streaming content can be a digital broadcast TV network or the Internet. It's possible to have integration, in the same device, of content coming from a broadcast and an interactive (online) connection.

Anticipated applications leveraging the AIC spec include graphic-rich electronic program guides with related cross links and on-screen program previews, home-shopping whereby consumers can inspect products via streaming video and 3-D images, and detailed 3-D replicas of historic sites. The spec might also make it possible for viewers to access bibliographical content and unused video footage.

Founders of the Advanced Interactive Content (AIC, pronounced "ace") initiative said they are hoping a variety of advanced multimedia technologies -- thus far developed and grown independently -- will finally converge on a common platform. The group said it plans to draft the spec before the end of this year.

Taking part in the AIC meeting were representatives from the Motion Picture Experts Group, Virtual Reality Modeling Language organization, and Advanced Television Systems Committee (ATSC). The initiative will "write an open specification to integrate and harmonize VRML, MPEG-4, and Broadcast HTML [BHTML] into a seamless stream," said Rob Glidden, co-chairman of VRML 3-D Integrated Media Working Group and one of 12 founding members of AIC.

Common Goal

To a certain degree, the new initiative shares a common objective with the Intel-led Advanced Television Enhancement Forum (ATVEF). Both aim to create a content-programming platform for a broadcast environment.

The AIC proponents, however, are going a few steps further, according to Cliff Reader, a key player in the MPEG-4 standard development and also an AIC founding member.

"While many in the industry today are thinking how they can add HTML to TV," Reader said, "our vision is how we can create a rich set of 2-D and 3-D objects, audiovisual streaming content in a broadcast environment, for which HTML -- or an application like seeing Web pages on a TV -- may be only a part."

ATSC's DTV Application Software Environment group is examining two competing proposals, one by ATVEF and the other being refined by the Broadcast HTML team within the DTV Application Software Environment group. BHTML, written in the emerging Extensible Markup Language (XML), is designed for tight integration with the Java framework.

Given that AIC lists the chairman of the DTV Application Software Environment group as well as the BHTML team leader among its founders, it's no wonder the effort is already causing a stir among ATVEF backers. (The DTV Application Software Environment group chairman is Aninda DasGupta of Philips Research; Ted Wugofski of Gateway is the BHTML team leader.)

Some said they believe the motivation is to promote BHTML, even if the ATSC doesn't wind up ratifying that technology. One executive in the ATVEF camp, who spoke on the condition of anonymity, warned, "The AIC, not being a due-process standards body, is in questionable territory if it presumes to invoke an international platform standard based on BHTML."

AIC members vigorously disagree. AIC is founded mostly by individual technical leaders of industry forums and is committed to serving as integrator of disparate standards. It is not a consortium of corporations vying to promote a proprietary spec.

"This [AIC] is not yet another forum to set a standard," said Glidden.

Pointing to longstanding integration efforts between VRML and XML, as well as between MPEG-4 and VRML, Glidden said, "This is a natural extension of what we have been doing at each of the groups."

Moreover, the initiative fills gap in work done by each group thus far. Each member is responsible for sharing any developments discussed in AIC with his original standards body. Thus, after drafting a spec, the AIC members would have to win over the appropriate bodies and get the specification approved there. "We see ourselves more as a facilitator," Glidden said.

As for BHTML, Glidden said, "Although we see BHTML as a good technical solution, we have no intention to replace the development work by the BHTML team at the DTV Application Software Environment group. Nor will our work within the AIC be dependent upon their BHTML development. We may end up finding a solution similar to BHTML, but not necessarily BHTML itself."

Getting To The Crux Of The Problem

AIC founders appear to believe the problem they must solve is fairly straightforward. Because there is no well-defined way to integrate such key technologies as VRML, MPEG-4, and BHTML, their job is to develop and specify syntax and tools for this integration. More specifically, they plan to add a BHTML stream to MPEG-4, while defining "an integration of language and interface between BHTML and VRML/Binary Format for Scenes," or BIFS, said Glidden. In his view, BIFS and VRML are dual representations of the same content, BIFS in a binary form, and VRML in a textual.

As for tools, "The use of MPEG-4 in this integration effort is a marriage made in heaven," said Reader. MPEG-4, an object-oriented data representation, uses the same tools as MPEG-2, compressed digital audio/video streams. The two share the same timing model, the same clock reference, and the same time stamps.

"All these things allow a perfect synchronization between MPEG-4's objects and DTV audio/video streams, a precisely guaranteed quality of service," Reader said. "The exact lip-sync experience of streaming can now be fused with 3-D graphics objects and VRML."

The AIC founders said they believe no new technology is needed for such an integration work. And while there may be a few ways of integrating these tools, they hope to specify just one.

The AIC initiative has already set a very tight and ambitious schedule. The group will deliver the spec by December and validate it in a working implementation by March 1999. The group set the timetable by mapping its efforts onto the concurrent time line set for the open standards processes of MPEG, VRML, and ATSC.

Noting that the dozen AIC founders are all experts in actually writing specifications in their respective standards organizations, "We set the schedule by already allocating resources from our members," said Glidden. He also promised commercial products based on the new spec can be launched in the fourth quarter of next year.

Content developed on a platform based on the newly integrated spec will be delivered by using MPEG-2 or IP transport protocols. The network infrastructure used for the delivery of integrated 2-D, 3-D, and streaming content can be a digital broadcast TV network or the Internet. It's possible to have integration, in the same device, of content coming from a broadcast and an interactive (online) connection.

Anticipated applications leveraging the AIC spec include graphic-rich electronic program guides with related cross links and on-screen program previews, home-shopping whereby consumers can inspect products via streaming video and 3-D images, and detailed 3-D replicas of historic sites. The spec might also make it possible for viewers to access bibliographical content and unused video footage.

Such gateways provide three basic functions:
-Interface between the PSTN network and the Internet