Update of RFC 2838, tv: URI

["Deventer, M.O. \(Oskar\) van" <[e-mail]>]

All,

We see a need for an update to RFC 2838, which is about the tv: URI for
the identification of television channels. After speaking with Lisa
Dusseault, Cullen Jennings suggested discussing such an update on the
[e-mail] email list. The rest of this email describes the
use cases, the problem statement, a rough proposal and items for the
proposed update. We would like to invite feedback on these.

Background: RFC 2838 for the identification of TV channels

Unambiguous identification is needed when applications refer to TV
channels. An example use case is clickable TV watching advice in an
instant messaging application: "He John, check out BBC1 now". Another
example use case is a presence application: "Your buddy John is now
watching TV5". There does not exist an international naming authority
for the identification of TV channels. RFC 2838 defines a harmonized
alternative solution, namely the tv: URI. These DNS-style identifiers
are deduced from the name of the broadcaster or television network, its
nationality and possibly the name of the broadcast stream. The
assumption of RFC 2838 is that the deduction of a tv: URI is
unambiguous, which is usually true in the American context. Here are
some tv: URI examples from RFC 2838: tv:wqed.org; tv:nbc.com;
tv:abc.com; tv:abc.co.au; tv:east.hbo.com; tv:west.hbo.com.

Problem: Ambiguities with RFC 2838 in a European context

Because of the public network system in several European countries, the
deduction of tv: URIs leads to ambiguities in the European context. In
the Netherlands, for example, the public network system has more than
ten TV stations who alternatingly broadcast on the three public TV
channels. At one time, one TV station may be broadcasting different
programs on different channels. Another issue is "code sharing" where
cable companies broadcast on one TV channel different (foreign) TV
channels at different times, e.g. a children's channel at day time and a
film channel at evening time. In all these examples, the deduction of a
tv: URI for the TV channels is ambiguous.

Proposal: Take the website name of the TV channel

Our proposal is to deduce the name of the TV channel from the name of
its official website. After a small investigation, we found that every
TV channel seems to have a dedicated website. American TV channels,
public TV channels in Europe and even small local TV channels have their
own website. So that removes the problem of ambiguities. The deduction
of a tv: URI then becomes a no-brainer: take the website name and
replace "http://" by "tv:". Here are some examples of European tv: URIs
using this convention: tv:bbc.co.uk/bbcone; tv:nederland1.nl; tv:tv5.fr.

Update to RFC 2838: syntax and synonyms

-The proposed new RFC that updates RFC 2838 would keep most parts of RFC
2838 unaffected. The American tv: URI examples of RFC 2838 would remain
unchanged, as these tv: URIs do already match with a website. The
Australian ABC channel would become tv:abc.net.au, corresponding to
their actual website name.
-There is an update to the RFC 2838 syntax needed, as some TV channels
would be identified by a resource (using "/") in our proposal and not
only by a domain name. Two examples of this are tv:bbc.co.uk/bbcone and
tv:nationalgeographic.nl/channel.
-Another issue for the update is synonyms. Some websites work both with
and without the "www" part in its URI. Some websites redirect to other
websites. The website http://nederland1.nl redirects to
http://portal.omroep.nl/ned1. In order to achieve the highest level of
interoperability, synonyms should be accepted as names of TV channels.

Please let us know your reaction on this proposal.

Best regards,

Oskar

--------------------------------
dr.ir. M. Oskar van Deventer
TNO Information and Communication Technology
P.O. box 5050
2600 GB  Delft
Netherlands
[phone]
[e-mail]
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