[opendtv] Re: IP-Based TV Will Revolutionize Entertainment

  • From: Craig Birkmaier <craig@xxxxxxxxx>
  • To: opendtv@xxxxxxxxxxxxx
  • Date: Sat, 30 Apr 2005 08:27:27 -0400

At 6:30 PM -0400 4/29/05, Manfredi, Albert E wrote:
>This goes back to these comments:
>>  As we told the FCC back before 1995, they only needed
>>  to do two things.
>>  Choose a modulation standard and a transport stream
>>  standard. Everything else can be driven by the
>>  marketplace.
>>  The analogy to this is Ethernet and TCP/IP.
>XML didn't exist in 1995, but something was needed

Once again Bert takes things out of context.

In the 1995 context, the referral to a transport stream standard 
implied two things:

1. A standardized way of packetizing the data that is carried by the systems;

2. The uses of headers and descriptors to identify the contents of the packets.

These issues were discussed extensively inside of the ACATS process 
(which recommended the same) and in the ATSC, which eventually 
adopted the MPEG-2 transport stream and a bunch of proprietary 
header/descriptor garbage which most vendors still do not implement 
properly . Hence the high level of list traffic about PSIP, Directed 
Channel Change et al).

Ten years later the marketplace HAS come to understand the important 
role of metadata as it relates to the delivery of all kinds of 
information via digital networks. During that time the SMPTE has 
developed parallel standards for the video industry, but their 
efforts were too little too late, and narrowly defined for a vertical 
industry market. The SMPTE MXF standard is implements in the 
equipment from several vendors, but many others are using XML.

XML has emerged as the marketplace standard for the handling of 
metadata, and companies are scurrying around writing filters to 
convert MXF into XML and back.

You see Bert, the marketplace really does work. It is the efforts of 
industries that are seeking to build walls around their little 
empires that cause most of the headaches.

The ATSC standards may become a case study in futility for the next 
generation of Harvard MBAs.

It is also worth noting that the requirements for a one-way broadcast 
network versus a two-way IPTV network are NOT the same. As Kon points 
out, you can burn up significant bandwidth using the network to pull 
data that should be pushed to every receiver. With a broadcast 
network there is little choice - although it is possible to use a 
back channel to send requests for data, it is far more efficient to 
push data and let the receivers filter out what they need.

For IPTV networks the same rules still apply to some extent. It is 
more efficient to broadcast the stuff that everyone needs, and pull 
the private stuff. Thus these system use IP multicast on the 
backbones and routing close to the home to select the streams for 
individual users.

I'm quite certain I could find several megabytes of messages from 
Bert trying to teach us all of this a few years ago...


You can UNSUBSCRIBE from the OpenDTV list in two ways:

- Using the UNSUBSCRIBE command in your user configuration settings at 

- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word 
unsubscribe in the subject line.

Other related posts: