W3C home > Mailing lists > Public > www-archive@w3.org > April 2004

.mobi considered harmful

From: Tim Berners-Lee <timbl@w3.org>
Date: Fri, 30 Apr 2004 19:13:59 -0400
Message-Id: <0FF4CB59-9AFC-11D8-A8E0-000A9580D8C0@w3.org>
Cc: Public W3C <www-archive@w3.org>
To: stld-rfp-mobi@icann.org

This text is from the current state of 
Tim BL

                    New top level domains considered harmful

      In 2004 there were proposals to create new top-level domains which
      included .mobi and .xxx. There are major problems with these
      proposals. The short answer is that it is unwise, as an
      architectural principle, to put semantics into names. However, this
      may not not enough to explain to its proponents what is wrong with
      the idea. This article attempts to elaborate a little. There are
      costs in general to creating any new top level domain. There are
      specific ways in which the ".mobi" breaks the web architecture of
      links, and attacks the universality of the web.


    When the Internet was being collaboratively developed by a
    substantially technical community around a growing but still
    manageable Internet Engineering Task Force, the Domain Name System
    (DNS) evolved as a hierarchical solution to the problem of keeping
    track of which computers had which Internet Protocol (IP) addresses.
    The tree structure was an improvement over the previous flat space of
    host names. It reduced the chaos, by allowing new names to be
    allocated in sub-domains without recourse to a central registration
    system. Because the frequency of allocation of new names decreased as
    one ascended the tree toward the root, the actual cost was kept

    As email and World Wide Web (WWW) use blossomed and became
    increasingly important, domain names crept out of the messages syntax
    for Internet protocols and crept into daily parlance. It then became
    valuable to own a short domain name. This turned domain name space
    into a limited commodity. After some tussles for control (ongoing at
    the time of writing) and some large amounts of money changing hands 
    some cases, the system has now settled down to a market-based one in
    which names can be rented, transfer value can be asked by the old
    owner of the new owner, and one-time and annual fees are typically
    payable by any domain to any company managing the higher domain. An
    anomaly was that unclaimed names were deemed to have no owner and no
    value, and were allocated in a "first come first served" frenzy in
    which speculators made great profits and held to ransom those who may
    have been considered the more logical owner of a name. This anomaly
    created great instability. It has costs, in that any trademark owner
    had to beware of parties who would register domains which included
    their trademark. The Example Manufacturing Company had to ensure that
    it owned not only example.com which it had used for email and web 
    for many years, but also example.net and example.org to avoid
    unscrupulous competition setting up sites to benefit from Example's
    excellent reputation. As the business grew, Example had to also
    acquire example.fr and example.co.uk to ensure that confusion was

    The fact was that the public memory was not for the domain name, but
    for the brand name which was sandwiched between www and .com. To this
    extent, in the world of memorable domain names, the
    hierarchicalization of the domain system had failed to happen. In the
    public's memory, example was the mark, and the difference between
    example.com and example.net merely a source of confusion.

    As each node in the tree represents a potentially valuable asset,
    control of any subset of the tree is valuable. Control of the entire
    tree is managed by ICANN, which is set up to be a non-profit
    international institution, with the intent that it should as such
    carry the trust of the entire community in its efforts to manage the
    system for the common good. Control of subtrees such as .net, .com 
    .org is delegated to set of parallel registries whose business model
    is nominally the charging of registration and annual fees. There have
    been temptations for the registry companies to consider themselves
    owners of unclaimed names. Rumors have abounded about systems which
    would automatically rent a domain name about which a potential renter
    was inquiring, or would redirect traffic from an unclaimed Web site 
    their own Web site, and so on.

The Cost of Change

    The top level of the domain name system, and to a lesser extent the 
    address space, are the single weak, centralised, points of an
    otherwise strong, decentralised system. The Internet is a net, and 
    WWW is a Web, but WWW and email use DNS which is a tree, which has a
    single root. Although there are many benefits to a system with global
    identifiers, there are also costs, such as a single common DNS tree.
    As a community we have all decided that the benefits of the system
    (such as being able to quote example.com anywhere in the world and
    have it mean the same thing) outweigh the costs of the social systems
    required to ensure fairness in its operation. There is, however, 
    stress. ICANN is under constant pressure to alter its balance of 
    or modus operandi. It balances technical, academic, commercial, and
    governmental inputs. The whole issue of domain names has created a
    vast amount of concern. And because the DNS tree is so fundamental to
    the Internet applications which build on top of it, any uncertainty
    about the future creates immediately instability and harm.

    Our first instincts, then should be not to change the system with
    anything but incremental and carefully thought-out changes. The
    addition of new top-levels domains is a very disturbing influence. It
    carries great cost. It should only be undertaken when there is a very
    clear benefit to the new domain. In the case of the proposed .mobi
    domain, the change is actually detrimental.

The Economics of Domain Names

    In practice, for most domain name owners, the part between the "www"
    and the top level domain is their brand, or their name. It is
    something they need to protect. This means that in practice, a 
    organization to avoid confusion has to own its domain in every
    non-geographical top level domain. For a large company, the cost of
    this may be insignificant. For a small enterprise, a non-profit
    organization or a family, the cost becomes very significant.

    The chief effect of the introduction of the .biz and .info domains
    appears to have been a cash influx for the domain name registries.
    Example Inc. as mentioned above owns example.com, org and .net. Does
    it also have to buy .biz, .info, and .name to avoid confusion and the
    misappropriation of my name by others? Will I have to also rent
    "example.mobi" in case it want to make information available for
    people who use wireless equipment?

    The market for second-level domains is a market for a limited
    resource. After an unstable period when the first come first served
    system was in play and greedy squatters grabbed domains simply for
    speculation, it has now settled down. Introducing new TLDs has two

    The first effect is a little like printing more money. The value of
    one's original registration drops. At the same time, the cost of
    protecting one's brand goes up (from the cost of three domains to
    four, five, ...).

    The value of each domain name such as example.com also drops because
    of brand dilution and public confusion. Even though most people
    largely ignore the last segment of the name, when it is actually used
    to distinguish between different owners, this increases the mental
    effort required to remember which company has which top level domain.
    This makes the whole name space less usable.

    Is it fair to reduce the value of these domains which have been
    acquired at great cost by their owners?

    The second effect is that instability is brought on. There is a 
    of activity to reserve domain names, a rush one cannot afford to miss
    in order to protect one's brand. There is a rash of attempts to steal
    well-known or valuable domains. The whole process involves a lot of
    administration, a lot of cost per month, a lot of business for those
    involved in the domain name business itself, and a negative value to
    the community.


    As we have seen, the choice of a tree structure for domain names is
    one which has costs and benefits, and the community currently accepts
    both. The cost of confusion, and of extra name registrations, is 
    When the benefits of the new domain itself are small or negative (as
    we discuss below), then one looks for incentive. The large amount of
    money that has changed hands for domain names might lead a person to
    suspect that this was the motivation. Under these circumstances, to
    increase public trust, proposals from non-profit organizations would
    raise less suspicion.

    The root of the domain name system is a single public resource, by
    design. Its control must be for and, indirectly, by the people as a
    whole. To give away a large chunk of this to a private group would be
    simply a betrayal of the public trust put in ICANN.

Specific problems with .mobi

    The different domains are introduced for different reasons, so we 
    answer this for each one. The [2]ICANN list of proposals gives
    pointers to the proposals.


    The .mobi domain is described as being for the use of a community. To
    quote the proposal, the target community for the .mobi TLD is:

      * Individual and business consumers of mobile devices,services and
      * Mobile content and service providers
      * Mobile operators
      * Mobile device manufacturers and vendors
      * IT technology and software vendors who serve the mobile community

    This is in fact a mixture of reasons. It sounds as though there is a
    use for ".mobi" when the provider of a service intends it to be for
    the benefit of mobile users. There appears to be a desire to limit 
    use of ".mobi" to companies -- perhaps those in the group.

    This domain will have a drastically detrimental effect on the Web. By
    partitioning the HTTP information space into parts designed for 
    from mobile access and parts designed (presumably) not for such
    access, an essential property of the Web is destroyed.

   Device Independence.

    The Web is designed as a universal space. Its universality is its 
    important facet. I spend many hours giving talks just to emphasize
    this point. The success of the Web stems from its universality as do
    most of the architectural constraints.

    The Web must operate independently of the hardware, software or
    network used to access it, of the perceived quality or 
    of the information on it, and of the culture, and language, and
    physical capabilities of those who access it [@@WTW]. Hardware and
    network independence in particular have been crucial to the growth of
    the Web. In the past, network independence has been assured largely 
    the Internet architecture. The Internet connects all devices without
    regard to the type or size or band of device, nor with regard to the
    wireless or wired or optical infrastructure used. This is its great
    strength. From its inception, the Web built upon this architecture 
    introduced device independence at the user interface level. By
    separating the information content from its presentation (as is
    possible by mixing HTML with CSS, XML with XSL and CSS, etc.) the Web
    allows the same information to be viewed from computers with all 
    of screen sizes, color depths, and so on. Many of the original Web
    terminals were character-oriented, and now visually impaired users 
    text-oriented interfaces to the same information.

    For a time, many Web site designers did not see the necessity for 
    device independence, and indicated that their site was "best viewed
    using screen set to 800x600". Theose Web sites now look terrible on a
    phone or, for that matter, on a much larger screen. By contrast, many
    Web sites which use style sheets appropriately can look very good on 
    very wide range of screen sizes.

    It is true that to to optimize the use of any device, an awareness on
    the part of the server allows it to customize the content and the
    whole layout of a site. However, the domain name is perhaps the worst
    possible way of communicating information about the device. Devices
    vary in many ways, including:
      * Network bandwidth at the time,
      * Screen size and resolution,
      * Intermittent or continuous connectivity,

    and so on. While with the current technology, the phrase "Mobile" may
    equate roughly in many minds to "something like a cell phone", it is
    naive -- and pessimistic -- to imagine that this one style of device
    will be the combination that will endure for any length of time. Just
    as concepts such as the "Network PC" and the "Multimedia PC" which
    defined profiles of device capability were swept away in the onrush 
    technology, so will an attempt to divide devices, users and content
    into two groups. Small devices will have high bandwidth. Devices with
    large screens will sometimes have small bandwidth. Some "mobile"
    phones will be permanently mounted on kitchen walls. The range of
    digital assistants will continue to evolve.

    There are good ways to deal with and derive the greatest benefit from
    the growing diversity of client devices. The CC/PP specifications
    provide a framework for a client device to describe its capabilities
    in great detail. This is based partly on the UAPROF (User Agent
    Profile) specifications developed by the mobile phone industry. Also,
    the HTTP specification has a content negotiation mechanism which
    allows a device to give a simple profile of its capabilities whenever
    it asks for some information. These systems are much more powerful
    than a top level domain name.

    The various documents about the ".mobi" Top Level Domain talk about
    not only mobile devices but "mobile users" and "mobile businesses".
    There is an indication that the mobile technology providers feel that
    while one is mobile, or when one is catering to a mobile customer, 
    is special or different. This may in fact be motivated simply by
    attempts to get the mobile communications supplier's name more
    visible. It may be connected with a hope by the communication
    providers to gain some control of over information flow to and from
    mobile users. This would be detrimental to the open markets enabled 
    the Internet.

    If neither of these motivations are the cause, then perhaps there is
    an honest belief that being mobile will indeed be best when it is
    visible to end users. In other words, the mobile communications
    providers are expecting to declare failure. It is failure when a
    communications system, in providing connectivity, becomes foremost in
    the user's perceptions. A travel agent should be a travel business,
    not a "mobile business". In a reasonable world, the travel agent gets
    on with selling flights and not worrying about whether a customer is
    attached by a wire. In a reasonable world, a phone is a phone and the
    particular electromagnetics used to connect it to another phone are
    totally uninteresting compared to the fact that a person is connected
    to another person.

   Damage: Loss of web functionality

    But the point is not that a division into ".mobi" and the
    ("immobile?") rest of the world is futile, it is that it is harmful.

    The Web works by reference. As an information space, it is defined by
    the relationship between a URI and what one gets on using that URI.
    The URI is passed around, written, spoken, buried in links,
    bookmarked, traded while Instant Messaging and through email. People
    look up URIs in all sorts of conditions.

    It is fundamentally useful to be able to quote the URI for some
    information and then look up that URI in an entirely different
    context. For example, I may want to look up a restaurant on my 
    bookmark it, and then, when I only have my phone, check the bookmark
    to have a look at the evening menu. Or, my travel agent may send me a
    pointer to my itinerary for a business trip. I may view the itinerary
    from my office on a large screen and want to see the map, or I may
    view it at the airport from my phone when all I want is the gate

    Dividing the Web into information destined for different devices, or
    different classes of user, or different classes of information, 
    the Web in a fundamental way.

    I urge ICANN not to create the ".mobi" top level domain.

    Tim Berners-Lee

     Personal Opinion
     Cambridge, Massachusetts, USA, 30 April 2004


    See also:

    [UW]: Berners-Lee, T., Universality of the WWW, Japan prize
    commemorative lecture, Tokyo, 2004. [3]slides]

       [3] http://www.w3.org/2002/Talks/04-univ/slide1-3.html

    [WTW]: Berners-Lee, T. [4]Weaving the Web, HarperSanFrancisco, 1999.

       [4] http://www.w3.org/People/Berners-Lee/Weaving

    [IJ]: Jacobs, I.: [5]Why Using TLDs for Filtering is Ineffective,
    Harmful, and Unnecessary Public communication. 2004

       [5] http://www.w3.org/2004/03/28-tld
Received on Friday, 30 April 2004 19:14:00 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:32:27 UTC