📄 rfc1943.txt
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wide range of applications. Whereas globally integrated projects must
conform to a specific DIT, independent X.500 operations may define
unique DITs, object classes and attributes as per their specific
needs;
- X.500 is a good alternative for paper directories, offering the
ability to update and modify in an interactive mode. This allows a
company to provide the most current information with less cost and
effort;
- because of the electronic base of X.500, other electronic
applications may interact with the application without human
intervention.
The benefits for global directory use are:
- the distributed nature of X.500 is well suited for large global
applications such as the White Pages Directory. Maintenance can be
performed in a distributed manner;
- X.500 offers good searching capabilities from any level in the DIT.
Also with "User Friendly Naming" in place, searches are very
intuitive;
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RFC 1943 Building an X.500 Directory Service in the US May 1996
- there are DUA interfaces for the White Pages service available for
all types of workstations. For an overview of X.500 software reference
RFC1632.
- X.500 is an international standard. Using such a standard ensures
interoperability within the worldwide base.
2.5 Other Applications of X.500
In addition to the White Pages, X.500 can be used as a source for any
type of information that needs a distributed storage base.
The University of Michigan is using X.500 for electronic mail
routing. Any mail coming to the university domain, umich.edu; gets
expanded out to a local address that is stored in the rfc822Mailbox
attribute. The University also operates a standard X.500 name server
which provides name lookup service of over 200,000 names. They use
the Lightweight Directory Access Protocol (LDAP) [11].
An implementation of the X.500 Standard directory service has been
incorporated into the Open Software Foundation (OSF) Distributed
Computing Environment (DCE). This component, known as the Global
Directory Service (GDS), provides an area where distributed
application clients can find their application servers. The GDS, in
response to requests made by other clients, provides the unique
network address for a particular DCE resource. Because it is based
on a international standard, GDS can offer access to resources among
users and organizations worldwide. This scalable service can be
performed in DCE environments that range in size from the very small
to the very large.
Lookup services can be implemented into a variety of applications.
Cambridge University in Great Britain implemented the X.500 directory
service into an employee locator application. Based on badge sensors
at strategic locations, this application can determine the
whereabouts of an employee on the campus. As the individual moves
about, the sensors register their location in an X.500 Directory.
Digital Signature Service (DSS) and Privacy Enhanced Mail (PEM) work
on the principal of a directory key server which generates and
provide users with "public" codes that match previously registered
"private" codes. Only the recipient can decipher messages sent in
this fashion. The X.509 [4] standard for key certificates easily fits
within the structure of the X.500 Directory Service.
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RFC 1943 Building an X.500 Directory Service in the US May 1996
3.0 Legal Issues
3.1 Introduction
Currently in the United States, there are no specific legal rules for
the information that is provided via an electronic directory service.
Various organizations and groups associated with usage of the
Internet, noting a need to address privacy and data integrity issues,
have prepared directives to address this issue. Two such areas
addressed are those of the rights of registrants included in the
directory and the responsibility of administrators to guarantee the
integrity of such data.
Registries containing information that is related to an individual is
freely transferred and unregulated in the US, unless the provider of
the data is an agency or an holder of sensitive information as
defined by federal legislation and further may differ for each state.
An agency is defined as: any executive department, military
department, Government corporation, Government controlled
corporation, or other establishment in the executive branch of the
Government (including the Executive Office of the President), or any
independent regulatory agency. Sensitive data can be financial
records, medical records, and certain legal documents. As previously
noted, each state has their own legislation on sensitive or private
data.The registered persons have little recourse to control list
information short of filing a lawsuit against the information
provider.
For individuals who transfer data across country boundaries, it is
important to understand that other countries may have legislation to
regulate data. Prior to requesting list information from these
countries, an administrator should review applicable legislation and
have some mechanism in place to ensure how data will be handled once
it is crosses the border. Policy Statements for some countries have
been prepared and are provided for via Code of Conduct papers.
3.2 Purpose of the Directory
The operational intent including presentation data and list
registrants and access rights must be clearly defined and stated.
Initially this provides the skeleton of the DIT. Eventually a
statement such as this may provide a basis legally justifying the
directory.
All data presented must be defined in the purpose. If for example, a
directory is for the sole purpose of providing professional
addressing information - an entry would include name, postal address,
office telephone, facsimile number, electronic mail address and
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RFC 1943 Building an X.500 Directory Service in the US May 1996
company name. Private address information listing the home address
or phone would be prohibited as would any other information not
directly related to addressing.
3.3 User Rights
The North American Directory Forum (NADF) has published a document
that defines the User Bill of Rights [5]. This document defines an
individuals rights regarding the public release of personal or
private information. Among other issues stated, the user has the
right to be notified regarding the inclusion of their information in
a data registry as well as the right to examine and have incorrect
information changed.
This paper is specifically written for the North American Directory
Forum and recommends compliance with US or Canadian laws regulating
privacy and access information.
Although current US legislation does not include all the suggestions
in this document, it is the responsibility of the controller of the
data to respect the rights of the individuals. These recommended
rules can be seen as respect for the individual and the considerate
controller will follow these guidelines within any boundaries that
they may be mandated by.
3.4 Data Integrity
An information provider has the responsibility to guarantee the data
that they make available to users. The integrity of a data source is
heavily weighted by the accuracy and timeliness of the contents.
Interoperable data sources must have concurrence of these factors as
well. The degree to which an information provider can guarantee the
validity of the data that they present, reflects on the validity of
the provider in general. RFC 1355 [6], suggests that a data source
enable accuracy statements describing the process that the individual
NIC will use to maintain accuracy in the database.
In the European community, it is a legal requirement that the
information provider guarantee accurate data.
The controller of the information needs to be certain of the primary
source of data. When possible, the controller should develop routines
of random checks to validate the registry data for correctness.
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RFC 1943 Building an X.500 Directory Service in the US May 1996
3.5 Data Security
A Directory Service with non-authenticated access from the Internet
is difficult to protect from unauthorized use. Unauthorized use being
defined by each organization within the directory purpose statement.
Typical misuse being by individuals who attempt to duplicate the
directory for unauthorized purposes. Other security measures include:
Access Control Lists (ACLs), limitations on number of entries
returned to a query, and time to search flags. The result of such
controls will affect the legitimate user as well as the user they are
intended to block.
An alternative that may provide protection from misuse is to create
and display an attribute with each entry stating non-approved usage.
This feature will also provide evidence of restricted use in the
event that a legal case is necessary to stop unauthorized access.
The responsibility again falls on the data provider/implementor of
the directory service. Astute programmers will create or make use of
existing tools to protect against data destruction, falsification,
and misuse.
3.6 Conclusions
User Rights, Data Integrity and Protection of data should not be
considered merely in an effort to abide by legal rulings; they should
be the intention of a good data source. A successful Directory
Service must be aware of the requirements of those individuals
inclusive in the list as well as those of the directory users.
In general, at the minimum the following conditions should be
observed:
1. Define the purpose of the Directory.
2. Initially inform all registrants of their inclusion in
a Directory.
3. Prevent the use of data beyond the stated purpose.
4. Limit the attributes associated to an entry within
boundaries of the purpose.
5. Work towards a suitable level of security.
6. Develop a mechanism to correct/remove faulty data
or information that should not be in the Directory.
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RFC 1943 Building an X.500 Directory Service in the US May 1996
4.0 Infrastructure
4.1 Introduction
The White Pages Project, currently operated by Performance Systems
International (PSI) provides a reliable QUIPU infrastructure for
sites wishing to provide their own X.500 directory. Started in 1989
as the NYSERNet White Pages Pilot Project it was the first
production-quality field test of the Open Systems Interconnection
(OSI) technology running on top of TCP/IP suite of protocols [7].
This pilot X.500 Directory, provided a real-time testbed for a
variety of administrative and usage issues that arise. Today, more
than 30 countries participate in the globally distributed project
with over 1 million entries. The White Pages pilot is one of 37 other
pilots cooperating to provide information in the Nameflow-PARADISE
directory; an European project.
Initially the software was public domain, QUIPU X.500 [8]. This
"shareware" application in conjunction with administrative services
provided free of charge by PSI, allowed for a truly distributed X.500
Directory Service to operate.
In keeping with the Internet rules of operation, the lack of the US
regulations, the suggestions of North American Directory Forum and
the Internet Engineering Task Force (IETF), the complications that
arise from multi-distributed data as a service can be overwhelming.
PSI took on the challenge to provide such a service, and continues to
ensure operations today.
4.2 A Well Maintained Infrastructure
This distributed information service involves the cohesive effort of
all of the participating organizations. The ISO Development
Environment (ISODE) implementation of the OSI Directory, provided the
attributes and uniformity to facilitate this effort.
The primary DSA for the PSI Project is named Alpaca. Operating on a
Sun Sparc 10 with 120 megabytes of memory, this host serves as the
Master for the DSAs of 117 organizations under c=US. Redundancy for
Alpaca is provided by two sources, Fruit Bat operated by PSI and Pied
Tamarin operated by the InterNIC. Slave updates to this host are
provided on a nightly basis from the individual DSAs.
The data presentation is hierarchical in nature and emulates the
common white pages telephone book. The information provided contains
at minimum: a common name, voice phone listing, and electronic mail
addressing. Each entry has a uniqueness associates with it; the
relative distinguished name which is comprised of the entire
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