Network Working Group                                         D. Crocker
Request for Comments: 1775                        Brandenburg Consulting
Category: Informational                                       March 1995


                       To Be "On" the Internet

Status of this Memo

  This memo provides information for the Internet community.  This memo
  does not specify an Internet standard of any kind.  Distribution of
  this memo is unlimited.

Abstract

  The Internet permits different levels of access for consumers and
  providers of service.  The nature of those differences is quite
  important in the capabilities They afford.  Hence, it is appropriate
  to provide terminology that distinguishes among the range, so that
  the Internet community can gain some clarity when distinguishing
  whether a user (or an organization) is "on" the Internet.  This
  document suggests four terms, for distinguishing the major classes of
  access.

1.   INTRODUCTION

  The Internet is many things to many people.  It began as a technology
  and has grown into a global service.  With the growth has come
  increased complexity in details of the technology and service,
  resulting in confusion when trying to determine whether a given user
  is "on" the Internet.  Who is on the Internet?  What capabilities do
  they have?  This note is an attempt to aid Internet consumers and
  providers in determining the basic types of end-user access that
  distinguish critical differences in Internet attachment.

  The list was developed primarily for the perspective of users, rather
  than for the technical community. The definitions in this list take
  the perspective that users are primarily interested in application
  services.   A curious implication is that some of the definitions do
  not rely on the direct use of the underlying Internet connectivity
  protocols, TCP/IP.  For many technical discussions, therefore, these
  terms will not be appropriate.









Crocker                                                         [Page 1]

RFC 1775                To Be "On" the Internet               March 1995


2.   LABELS FOR INTERNET ACCESS

  The following definitions move from "most" to "least" Internet
  access, from the perspective of the user (consumer). The first term
  is primarily applicable to Internet service providers.  The remaining
  terms are primarily applicable to consumers of Internet service.

  FULL ACCESS

     This is a permanent (full-time) Internet attachment running
     TCP/IP, primarily appropriate for allowing the Internet community
     to access application servers, operated by Internet service
     providers.  Machines with Full access are directly visible to
     others attached to the Internet, such as through the Internet
     Protocol's ICMP Echo (ping) facility.  The core of the Internet
     comprises those machines with Full access.

  CLIENT ACCESS

     The user runs applications that employ Internet application
     protocols directly on their own computer platform, but might not
     be running underlying Internet protocols  (TCP/IP), might not have
     full-time access, such as through dial-up, or might have
     constrained access, such as through a firewall.  When active,
     Client users might be visible to the general Internet, but such
     visibility cannot be predicted.  For example, this means that most
     Client access users will not be detected during an empirical
     probing of systems "on" the Internet at any given moment, such as
     through the ICMP Echo facility.

  MEDIATED ACCESS

     The user runs no Internet applications on their own platform.  An
     Internet service provider runs applications that use Internet
     protocols on the provider's platform, for the user.  User has
     simplified access to the provider, such as dial-up terminal
     connectivity.  For Mediated access, the user is on the Internet,
     but their computer platform is not.  Instead, it is the computer
     of the mediating service (provider) which is on the Internet.

  MESSAGING ACCESS

     The user has no Internet access, except through electronic mail
     and through netnews, such as Usenet or a bulletin board service.
     Since messaging services can be used as a high-latency -- i.e.,
     slow -- transport service, the use of this level of access for
     mail-enabled services can be quite powerful, though not
     interactive.



Crocker                                                         [Page 2]

RFC 1775                To Be "On" the Internet               March 1995


3.   SAMPLE USAGE

  The test of a nomenclature is, of course, its application to real-
  life situations.  Two simple cases involve home users.  If a user
  accesses the Internet by running a terminal program on their PC and
  then dials up a public service which provides the Internet
  applications, then that user has Mediated Internet access.  The
  public service has Client or Full access, but the user does not.  On
  the other hand, users who access via SLIP or PPP are running Internet
  applications on their own PCs and they have Client Internet access.

  Many corporations now have a full-time link to the Internet.  The
  link is based on TCP/IP and usually has a number of Internet servers
  running, for email exchange and for making public corporate data
  available to the rest of the world, such as through the World Wide
  Web and Gopher.  Clearly, the corporation is "on" the Internet, with
  Full Internet access.

  What about a user in that corporation?  Many corporations today
  separate their internal internet from the public Internet via a
  firewall.  If a user from the internal internet has a desktop
  computer and reaches out to the Internet, through the firewall, by
  running any Internet applications, such as a Web browser, then that
  user has Client Internet access.

  Some corporations will not allow this, instead requiring all software
  which touches the public Internet to be run on specially-administered
  machines which are part of the corporation's firewall suite of
  services.  Hence, users must make a terminal connection to the
  special machines, from there running the Internet applications.  Such
  users have Mediated Internet access, the same as home users who dial
  up a public service.

4.   SECURITY CONSIDERATIONS

  This specification does NOT, itself, provide or define any security-
  related mechanisms.  However it does describe scenarios with
  different security implications for users and providers.  Readers of
  this discussion are cautioned to consider those implications when
  choosing a service.

5.   ACKNOWLEDGMENTS

  Development of these definitions was spurred by many public and
  private discussions in which confusion over Internet access reigned.
  Convergence on an initial set of three terms was the result of
  discussion on the Big-Internet mailing list, particularly from
  comments made by Alan Barret, Howard Berkowitz, Noel Chiappa, Steve



Crocker                                                         [Page 3]

RFC 1775                To Be "On" the Internet               March 1995


  Goldstein, Iain Hanson, Gary Malkin, Bob McKisson, Tim O'Reilly, Dave
  Piscitello and Bill Simpson.  Eventually, the need for a fourth
  category became evident and was discussed further with the
  participants on the list.  This does not mean that any of them
  necessarily endorses the terms and definitions provided, merely that
  their notes assisted my thinking on the topic.  After the initial
  round of public discussion, Smoot Carl-Mitchell and John Quarterman
  of Texas Internet Consulting developed terminology for similar
  categories and served to prompt modification of this set, described,
  here, to distinguish between provider and consumer forms of access
  and emphasize the role of Full access in defining the Internet core.

6.   Security Considerations

  Security issues are not discussed in this memo.

7.   Author's Address

  David H. Crocker
  Brandenburg Consulting
  675 Spruce Dr.
  Sunnyvale, CA 94086 USA

  Phone:    +1 408 246 8253
  Fax:      +1 408 249 6205
  EMail:    [email protected]

























Crocker                                                         [Page 4]