One document matched: draft-ietf-crisp-firs-core-01.txt
Differences from draft-ietf-crisp-firs-core-00.txt
INTERNET-DRAFT Eric A. Hall
Document: draft-ietf-crisp-firs-core-01.txt May 2003
Expires: December, 2003
Category: Standards-Track
The Federated Internet Registry Service:
Core Elements
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC 2026.
Internet-Drafts are working documents of the Internet Engineering
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Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document describes the core technical elements of the
Federated Internet Registry Service (FIRS), a distributed service
for storing, locating and transferring information about Internet
resources using LDAPv3.
Internet Draft draft-ietf-crisp-firs-core-01.txt May 2003
Table of Contents
1. Introduction...............................................3
2. Prerequisites and Terminology..............................3
3. The FIRS Namespace.........................................4
3.1. The domainComponent (dc=) Namespace Component...........4
3.2. The inetResources Namespace Component...................5
3.3. The Resource-Specific Namespace Component...............5
3.4. Referrals...............................................6
3.4.1. Subordinate reference referrals...................8
3.4.2. Continuation reference referrals..................9
4. Global FIRS Object Classes and Attributes..................9
4.1. The inetResources Object Class..........................9
4.1.1. Naming syntax.....................................9
4.1.2. Schema definition................................10
4.1.3. Example..........................................12
4.2. The inetAssociatedResources Object Class...............12
4.2.1. Naming syntax....................................13
4.2.2. Schema definition................................13
4.2.3. Example..........................................14
4.3. The referral Object Class..............................15
5. Global Query Processing Rules.............................15
5.1. Query Pre-Processing...................................16
5.2. Query Bootstrap Models.................................18
5.2.1. Targeted query processing........................18
5.2.2. Top-down processing..............................19
5.2.3. Bottom-up processing.............................22
5.2.4. SRV processing...................................25
5.3. Query Processing.......................................26
5.3.1. Matching filters.................................26
5.3.2. Query-volume restrictions........................28
5.3.3. Authentication restrictions......................29
5.3.4. Protocol and schema version controls.............29
5.4. Referral Processing....................................30
6. Security Considerations...................................33
7. IANA Considerations.......................................33
8. Author's Addresses........................................34
9. Normative References......................................34
10. Acknowledgments...........................................36
11. Changes from Previous Versions............................36
12. Full Copyright Statement..................................38
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1. Introduction
This specification defines the core object classes, attributes,
syntax rules, matching filters, and operational behaviors for the
FIRS service as a whole. Refer to [FIRS-ARCH] for information on
the FIRS architecture, and the resource-specific specifications
for definitions and rules which govern each of the different
resource-types.
The definitions in this specification are intended to be used with
FIRS. Their usage outside of FIRS is not prohibited, but any such
usage is beyond this specification's scope of authority.
2. Prerequisites and Terminology
The complete set of specifications in the FIRS collection
cumulative define a structured and distributed information service
using LDAPv3 for the data-formatting and transport functions. This
specification should be read in the context of the complete set of
specifications, which currently include the following:
draft-ietf-crisp-firs-arch-01, "The Federated Internet
Registry Service: Architecture and Implementation"
[FIRS-ARCH]
draft-ietf-crisp-firs-core-01, "The Federated Internet
Registry Service: Core Elements" (this document)
[FIRS-CORE]
draft-ietf-crisp-firs-dns-01, "Defining and Locating DNS
Domains in the Federated Internet Registry Service"
[FIRS-DNS]
draft-ietf-crisp-firs-dnsrr-01, "Defining and Locating DNS
Resource Records in the Federated Internet Registry
Service" [FIRS-DNSRR]
draft-ietf-crisp-firs-contact-01, "Defining and Locating
Contact Persons in the Federated Internet Registry Service"
[FIRS-CONTCT]
draft-ietf-crisp-firs-asn-01, "Defining and Locating
Autonomous System Numbers in the Federated Internet
Registry Service" [FIRS-ASN]
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draft-ietf-crisp-firs-ipv4-01, "Defining and Locating IPv4
Address Blocks in the Federated Internet Registry Service"
[FIRS-IPV4]
draft-ietf-crisp-firs-ipv6-01, "Defining and Locating IPv6
Address Blocks in the Federated Internet Registry Service"
[FIRS-IPV6]
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL"
in this document are to be interpreted as described in RFC 2119.
3. The FIRS Namespace
The FIRS namespace acts as an index to the federated partition
structure of the globally-distributed database of FIRS servers.
There are three major components to this namespace, which are:
* The domainComponent entries. Each partition of the globally
distributed FIRS directory database is represented by a
sequence of domainComponent distinguished names. These
sequences effectively identify the root scope of authority
for each partition in the global directory database.
* An inetResources entry. All of the FIRS-related resource-
specific entries in the global database are required to be
stored within a well-known "cn=inetResources" container
entry at the root of each directory partition. These well-
known entries act as application-specific access points
within the globally distributed directory database.
* The resource-specific entries. Each of the resource-
specific entries within the inetResources container entries
have their own unique naming rules, as defined in the
governing specifications for those resources.
These naming rules are discussed in more detail below.
3.1. The domainComponent (dc=) Namespace Component
The global FIRS directory database is divided into administrative
partitions, each of which represent a scope-of-authority for a
certain portion of the global database. The root of each partition
is represented by a sequence of domainComponent relative
distinguished names (RDNs), as defined in RFC 2247 [RFC2247]. In
this model, the scope-of-authority for a FIRS partition is derived
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from a domain name in the global DNS directory, meaning that
whoever has authority over any particular domain name effectively
has authority over the related FIRS partition.
Note that the domainComponent attribute is restricted to seven-bit
character codes, and is therefore effectively limited to using
character codes from US-ASCII [US-ASCII]. Due to this limitation,
internationalized domain names MUST be converted into their ASCII-
compatible forms using the "ToASCII" process defined in RFC 3490
[RFC3490] before the domainComponent RDNs are used in the
directory database or LDAP messages.
3.2. The inetResources Namespace Component
The FIRS-specific directory entries are segregated from other
application-specific entries by the use of a container entry with
the MANDATORY name of "cn=inetResources". Any entry which is to be
located through FIRS MUST refer to this container entry.
Note that this rule specifically applies to entries which are to
be located by FIRS clients. The entries themselves MAY be
referrals which reference entries in other locations if this is
necessary or desirable (see section 3.4), although it is important
for administrators to recognize that the referral targets will not
be locatable through FIRS.
3.3. The Resource-Specific Namespace Component
Every resource-specific entry also has a RDN which identifies that
resource within the context of the inetResources container of any
given partition. Examples of these resource-specific entries can
be seen in Figure 1 of [FIRS-ARCH], and include "cn=example.com"
which refers to the "example.com" DNS domain name resource, and
"cn=admins@example.com" which refers to the "admins@example.com"
contact resource.
Each of the FIRS resource-types have their own specific naming
rules which govern those resources. Refer to the resource-specific
specifications for information on those rules.
Note that the rules specifically apply to entries which are to be
located by FIRS clients. The entries themselves MAY be referrals
which reference entries in other locations if this is necessary or
desirable (see section 3.4), although it is important for
administrators to recognize that the referral targets will not be
locatable through FIRS.
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3.4. Referrals
FIRS allows entries in the namespace to refer to other entries, as
necessary or desirable. This model allows certain entries to be
created as "placeholders" for other canonical entries which
contain the actual data.
FIRS allows two methods for generating and processing these
referrals: subordinate reference referrals, and continuation
reference referrals.
Subordinate reference referrals indicate that the search base in
the original query is an alias for some other entry, and that the
query has to be restarted with a new search base in order for the
search operation to be processed. Meanwhile, continuation
reference referrals indicate that the search was successfully
initiated and that some data has been found, but that additional
queries for additional resources are required for the query to be
completely exhausted.
Subordinate and continuation reference referrals use the ref
attribute and referral object class defined in RFC 3296 [RFC3296].
Each of these mechanisms use LDAP URLs as defined in RFC 2255
[RFC2255] to carry referral data, with some additional FIRS-
specific restrictions.
Among these restrictions:
* Referral source entries MUST comply with all of the
applicable namespace and schema rules.
* Referral targets MUST use the domainComponent ("dc=")
naming syntax for their directory partitions. Although
other naming syntaxes are implicitly allowed by [RFC3296],
those syntaxes are only guaranteed to be resolvable if they
use domainComponent sequences.
* Referral targets are encouraged to reside in an
inetResources container entry, although this is not
required. For example, a general-purpose administrative
contact entry may need to refer to a user-specific contact
entry in another container if this is necessary, and this
kind of usage is allowed.
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* Referral sources and targets MUST have the same resource-
specific object class defined (for example, the referral
source and target for a DNS domain resource would both have
the inetDnsDomain object class defined). This is a
prerequisite for the proper handling of the search filters
specified in this document.
* Referral targets MAY exist as referrals to other entries,
but recursive referrals are discouraged. Clients MAY
discontinue referral processing after a reasonable amount
of effort (eight referrals is a suggested default value).
* The protocol identifier of a URL MUST specify the LDAP
service type. Although general-purpose LDAP referrals are
allowed to specify any kind of protocol, FIRS referrals are
intended to be used for automated queries, and the use of
other protocols is forbidden in the default case.
* URLs MAY specify host identifiers and port numbers, but
none of these elements are required.
* If a matching filter and/or assertion value needs to be
specified in the referral, they MUST be specified in the
filter element of the referral's LDAP URL. Matching filters
and/or assertion values MUST NOT be specified unless the
referral source needs to explicitly reference a specific
target entry in a specific partition. This should only be
necessary in those cases where the referral target entry
would not normally be located (most likely due to a
radically different entry name).
* The attribute, scope and extension elements of LDAP URLs
will be ignored by the client, and SHOULD NOT be provided.
* URLs MUST use a URL-safe format. For example, the IPv4 and
IPv6 network address syntaxes defined in this document make
use of the forward-slash ("/") character to indicate a
subnet prefix, and if this character needs to be provided
in a URL, it must be provided in the escaped form ("%2F" in
this example). Similarly, some domain names and email
addresses contain UTF-8 character data, and some of those
character codes will need to be escaped in order to be
passed as URL data.
* Implementations MUST NOT restrict URL values to verifiable
entries from local partitions. Implementations MAY validate
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referral targets in URLs, but a lack of knowledge regarding
a target MUST NOT be treated as sufficient cause to prevent
the referral target from being specified.
The rules for processing referral URLs are given in section 5.4.
Note that the "superior reference referral" defined in RFC 2251
[RFC2251] used as a "default referral" for out-of-scope searches
is explicitly unsupported in FIRS; any superior reference
referrals which are encountered as a part of this service are to
be treated as errors.
Each of the supported referral mechanisms are discussed in more
detail below.
3.4.1. Subordinate reference referrals
Subordinate reference referrals are defined in [RFC3296], and are
returned whenever the search base specified in a query exists as a
referral to some other entry. This means that the query MUST be
restarted, using the referral target as the new search base.
Any entries MAY be defined as subordinate reference referrals
which point to other entries. However, almost all of the search
functions defined for use by this service use the inetResources
container entry as the search base (the exceptions to this rule
are targeted searches for explicit entries), so subordinate
reference referrals will most commonly be seen when an
inetResources container entry has been redirected to an
inetResources container in another directory partition.
Servers MUST support the use of subordinate reference referrals
for this purpose, and clients MUST be prepared to accept and
process any subordinate reference referrals in answer sets.
When subordinate reference referrals are used for this purpose,
the referral source MUST be defined with the referral object
class, and MUST also be defined with the appropriate object class
for that resource type. For example, a "cn=inetResources" entry
which provided a subordinate reference referral would need to have
both the referral and inetResources object classes defined, while
a DNS domain resource such as "dc=example.com" would need to have
both the referral and inetDnsDomain object classes defined (among
the other object class definitions which were required for that
entry). Referral targets need to use whatever object classes are
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appropriate for the resource in question, and MAY also be
referrals to other entries.
3.4.2. Continuation reference referrals
Continuation reference referrals are defined in RFC 2251
[RFC2251], and are returned when a search operation has been
successfully processed but the answer data also includes referrals
to other entries. These referrals are often provided as
supplemental data to an answer set, although this is not required
(a continuation reference referral can be the only response, but
it won't be the only response in the common case).
Servers MUST support the use of continuation reference referrals
for this purpose, and clients MUST be prepared to accept and
process any subordinate reference referrals in answer sets.
When continuation reference referrals are used for this purpose,
entries MAY exist for the queried resource, but one or more
entries MUST exist with the referral object class defined, and
which provide LDAP URLs that point to other entries which have
additional information about the resource in question.
4. Global FIRS Object Classes and Attributes
Each of the schema definitions provided in this document include
attribute definitions, naming rules, and other definitions which
are designed to facilitate the consistent storage and retrieval of
information within the FIRS service.
4.1. The inetResources Object Class
The inetResources object class is a structural object class which
defines the attributes associated with the "cn=inetResources"
container entry, and which provides general information about the
network resources associated with the current directory partition.
4.1.1. Naming syntax
This document requires the presence of an entry named
"cn=inetResources" in the root of every directory partition which
provides FIRS services.
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4.1.2. Schema definition
Every directory partition which provides public FIRS data MUST
have a "cn=inetResources" entry in the root of the directory
partition. The inetResources entry MUST exist with the top and
inetResources object classes defined. If the entry exists as a
referral source, the entry MUST also be defined with the referral
object class, in addition to the above requirements.
The inetResources object class is a structural object class which
is subordinate to the top abstract class, and which MUST be
treated as a container class capable of holding additional
subordinate entries. The inetResources object class has one
mandatory attribute which is "cn" (the naming attribute), and also
has several optional attributes. Each of the other object classes
defined for use with FIRS are subordinate to the inetResources
object class and inherit its attributes.
The schema definition for the inetResources object class is as
follows:
inetResources
( 1.3.6.1.4.1.7161.1.0.0 NAME 'inetResources' DESC 'The
inetResources container for the FIRS service' SUP top
STRUCTURAL MUST cn MAY ( o $ ou $ description $
inetResourceComments $ businessCategory $ telephoneNumber $
facsimileTelephoneNumber $ labeledURI $
preferredDeliveryMethod $ physicalDeliveryOfficeName $
postOfficeBox $ postalAddress $ postalCode $ street $ l $
st $ c $ inetAbuseContacts $ inetGeneralContacts $
inetSecurityContacts $ inetTechContacts $
inetGeneralDisclaimer ) )
The attributes from the inetResources object class are described
below:
businessCategory, see RFC 2256 [RFC2256], section 5.16
c (country), see [RFC2256], section 5.7
cn (commonName), see [RFC2256], section 5.4
description, see [RFC2256], section 5.14
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facsimileTelephoneNumber, see [RFC2256], section 5.24
inetAbuseContacts
( 1.3.6.1.4.1.7161.1.0.2 NAME 'inetAbuseContacts' DESC
'Contacts for reporting abusive behavior or acceptable-use
policy violations.' EQUALITY caseIgnoreMatch SYNTAX
inetContactSyntax )
inetGeneralContacts
( 1.3.6.1.4.1.7161.1.0.3 NAME 'inetGeneralContacts' DESC
'Contacts for general administrative issues.' EQUALITY
caseIgnoreMatch SYNTAX inetContactSyntax )
inetGeneralDisclaimer
( 1.3.6.1.4.1.7161.1.0.4 NAME 'inetResourceComments' DESC
'General disclaimer text regarding this data' EQUALITY
caseIgnoreMatch SYNTAX DirectoryString{1024} )
inetResourceComments
( 1.3.6.1.4.1.7161.1.0.5 NAME 'inetResourceComments' DESC
'General comments about this entry' EQUALITY
caseIgnoreMatch SYNTAX DirectoryString{1024} )
inetSecurityContacts
( 1.3.6.1.4.1.7161.1.0.6 NAME 'inetSecurityContacts' DESC
'Contacts for general security issues.' EQUALITY
caseIgnoreMatch SYNTAX inetContactSyntax )
inetTechContacts
( 1.3.6.1.4.1.7161.1.0.7 NAME 'inetTechContacts' DESC
'Contacts for general technical issues.' EQUALITY
caseIgnoreMatch SYNTAX inetContactSyntax )
l (locality), see [RFC2256], section 5.8
labeledURI, see RFC 2079 [RFC2079]
o (organization), see [RFC2256], section 5.11
ou (organizational unit), see [RFC2256], section 5.12
physicalDeliveryOfficeName, see [RFC2256], section 5.20
postalAddress, see [RFC2256], section 5.17
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postalCode, see [RFC2256], section 5.18
postOfficeBox, see [RFC2256], section 5.19
preferredDeliveryMethod, see [RFC2256], section 5.29
st (stateOrProvinceName), see [RFC2256], section 5.9
street (streetAddress), see [RFC2256], section 5.10
telephoneNumber, see [RFC2256], section 5.21
4.1.3. Example
An example of the inetResources object class in use is shown in
Figure 1 below.
cn=inetResources,dc=example,dc=com
[top object class]
[inetResources object class]
|
+-attribute: o
| value: "Example Widgets' network resources"
|
+-attribute: inetGeneralContacts
| value: "admins@example.com"
|
+-attribute: telephoneNumber
| value: "1-800-555-1212"
|
+-attribute: inetResourceComments
value: "Please don't send complaints to the
postmaster@example.com mailbox."
Figure 1: The Example Widgets inetResources container entry.
4.2. The inetAssociatedResources Object Class
The inetAssociatedResources object class defines attributes which
are useful for cross-referencing entries with other resources. For
example, it allows inetOrgPerson entries to be associated with
IPv4 networks or DNS domains, providing generic cross-reference
pointer attributes (this information may be useful if a single
organization has multiple DNS domains registered). In short, any
resource can be associated with any other resource through the use
of this object class.
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4.2.1. Naming syntax
The inetAssociatedResources object class is an auxiliary object
class, and not a structural object class. Entries which use this
object class definition are defined under the rules associated
with the structural object class that defines the Internet
resource in question. As such, the naming rules associated with
that entry take precedence, and the inetAssociatedResources object
class does not define an independent naming syntax.
4.2.2. Schema definition
The inetAssociatedResources object class is an auxiliary object
class which is subordinate to the top object class. The
inetAssociatedResources object class has no mandatory attributes,
and only has optional attributes.
Although the inetAssociatedResources object class is subordinate
to the top object class, it is intended to be used with the
resource-specific structural object classes defined for use with
FIRS. The inetAssociatedResources object class is not likely to
provide much value when it is associated with the inetResources
object class, since the inetResources object class does not
specifically define any resources (and since it does not define
resources, it cannot define any associated resources). On the
other hand, it is reasonable for the inetAssociatedResources
object class to be associated with an inetOrgPerson object class
entry, particularly if the referenced person (or role) is
responsible for the management of multiple resources.
The inetAssociatedResources object class MUST NOT be associated
with an entry that only exists as a referral source.
Each of the associated resource attributes provide multi-valued
data, using the syntax notations which are specific to the
resource in question. For example, the inetAssociatedDnsDomain
attribute provides multiple associated DNS domain name resources
using a multi-valued array, with each domain name using the
inetDnsDomainSyntax naming rules defined in [FIRS-DNS].
The schema definition for the inetAssociatedResources object class
is as follows:
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inetAssociatedResources
( 1.3.6.1.4.1.7161.1.5.0 NAME 'inetAssociatedResources' DESC
'Internet resources associated with this resource.' SUP top
AUXILIARY MAY ( inetAssociatedContacts $
inetAssociatedDnsDomains $ inetAssociatedIpv4Networks $
inetAssociatedIpv6Networks $ inetAssociatedAsNumbers ) )
The attributes from the inetAssociatedResources object class are
described below:
inetAssociatedAsNumbers
( 1.3.6.1.4.1.7161.1.5.2 NAME 'inetAssociatedAsNumbers' DESC
'Autonomous system numbers associated with this Internet
resource.' EQUALITY caseIgnoreMatch SYNTAX
inetAsNumberSyntax )
inetAssociatedContacts
( 1.3.6.1.4.1.7161.1.5.3 NAME 'inetAssociatedContacts' DESC
'Other contacts associated with this Internet resource.'
EQUALITY caseIgnoreMatch SYNTAX inetContactSyntax )
inetAssociatedDnsDomains
( 1.3.6.1.4.1.7161.1.5.4 NAME 'inetAssociatedDnsDomains' DESC
'DNS domains associated with this Internet resource.'
EQUALITY caseIgnoreMatch SYNTAX inetDnsDomainSyntax )
inetAssociatedIpv4Networks
( 1.3.6.1.4.1.7161.1.5.5 NAME 'inetAssociatedIpv4Networks'
DESC 'IPv4 networks associated with this Internet
resource.' EQUALITY caseIgnoreMatch SYNTAX
inetIpv4NetworkSyntax )
inetAssociatedIpv6Networks
( 1.3.6.1.4.1.7161.1.5.6 NAME 'inetAssociatedIpv6Networks'
DESC 'IPv6 networks associated with this entry.' EQUALITY
caseIgnoreMatch SYNTAX inetIpv6NetworkSyntax )
4.2.3. Example
An example of the inetAssociatedResources object class is shown in
Figure 2 below.
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cn=192.0.2.0/24,cn=inetResources,dc=example,dc=com
[top object class]
[inetResources object class]
[inetIpv4Network object class]
[inetAssociatedResources object class]
|
+-attribute: description
| value: "The Example Widgets network"
|
+-attribute: inetAssociatedAsNumbers
| value: "65535"
|
+-attribute: inetAssociatedDnsDomains
value: "2.0.192.in-addr.arpa"
Figure 2: The inetAssociatedResources attributes associated with
the 192.0.2.0/24 IPv4 network entry.
4.3. The referral Object Class
Entries use the referral object class to define subordinate
reference referrals and continuation reference referrals, thereby
facilitating the programmatic redirection of queries in support of
the referral mechanisms defined in section 3.4.
Referral entries MUST conform to the schema specification defined
in [RFC3296].
Referral sources MUST NOT contain any user-definable attributes
(other than the mandatory naming attribute), and MUST NOT have any
subordinate child entries.
Refer to section 3.4 for the rules that govern referral URLs in
FIRS. Refer to section 5.4 for information on processing referral
URLs in FIRS.
5. Global Query Processing Rules
Another critical aspect to FIRS is the query-processing behavior.
These rules govern the ways in which a client parses a query,
locates a server which is authoritative for the resource being
queried, generates LDAPv3 queries, and processes any resulting
referrals. More specifically:
* Query pre-processing. The first step is for the client to
prepare the query. Portions of this process require the
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client to determine the type of resource being queried for,
and to determine the initial partition which should be used
for the query. Since this process is different for each
particular resource-type, the rules which govern this
behavior are defined in each of the resource-specific
specifications.
* Bootstrap processing. Once a partition has been determined,
the client must locate the LDAP servers which are
authoritative for the resource in question. Section 0
defines three different bootstrap models that clients can
use as part of this process, while each of the resource-
specific specifications define which of the models are to
be used for each particular resource-type.
* Query processing. Once a server has been located, the
client must submit the LDAP query which was formed during
the pre-preprocessing phase. Section 5.3 defines the global
considerations for all FIRS queries, while the resource-
specific specifications also define additional parameters.
* Query post-processing. FIRS explicitly supports different
types of LDAP referral mechanisms, any of which may result
in the client application restarting the query or
initiating a brand-new query. These mechanisms and their
behavioral rules are defined in section 5.4.
Each of these phases are discussed in more detail below.
5.1. Query Pre-Processing
Client input is generally limited to a single well-formed unit of
data, such as a domain name ("example.com") or an email address
("admins@example.com"), and this single piece of information must
be used to subsequently build a fully-formed LDAPv3 query,
including the assertion value, the search base, the matching
filter, and so forth. All of these steps are part of the pre-
processing phase.
Although the exact sequence of steps will vary according to the
resource-type being queried, there are some commonalities between
each of them. Among these steps:
* Determine the resource type. Different kinds of resources
have different processing steps, validation mechanisms, and
so forth, each of which require that the resource-type be
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appropriately identified. Clients MAY use any mechanisms
necessary to force this determination.
* Validate and normalize the data. In all cases, the input
data MUST be validated and normalized according to the
syntax rules defined in the specification which governs the
resource-type. As an example of this step, queries for
internationalized domain names must be validated and
normalized into a canonical UTF-8 form before any other
steps can be taken. Similarly, IPv6 addresses are required
to conform to specific syntax rules, and input address may
need to be expanded or compressed in order to comply with
the syntax requirements.
* Determine the authoritative directory partition for the
named resource. In most cases, the authoritative partition
will be a variation of the input query string, but this is
not always the case. For example, the default partition for
an email address will be extrapolated from the domain
component of the email address itself, while the
authoritative partition for an ASN uses a reserved
(special-purpose) domain name. In some cases, the
authoritative partition may change during the subsequent
query-processing steps.
* Determine the search base for the query. Each resource type
has resource-specific query-processing rules which will
dictate how the authoritative partitions are mapped to the
search base. In some cases, the cn=inetResources container
entry in the authoritative partition will be used "as-is",
while in other cases, the cn=inetResources container entry
in a delegation parent of the authoritative partition will
be used instead. In some cases, the search base may change
during subsequent query-processing steps.
* Determine the assertion value for the query. The assertion
value will usually be the normalized form of the input
query. In some cases, the assertion value may change during
subsequent query-processing steps.
* Determine the matching filter. Each resource-type has its
own matching filter rules. For example, contact entries are
matched with a simple equalityMatch comparison, while in
other cases the matching filter will be an extensibleMatch
which is peculiar to the resource-type in use.
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Once all of the pre-processing steps have been successfully
completed, the client will have to locate an LDAPv3 server which
is authoritative for the search base before it can submit the
query. This process is described in section 5.2 below.
5.2. Query Bootstrap Models
Once a client has determined which partition should be queried for
the specified resource, the client must determine which LDAP
servers are authoritative for that partition.
The FIRS service supports three different bootstrap models for
this process, although these models only differ in relatively
minor ways; once a server has been located, the rest of the query
process follows the same basic path (issuing the LDAPv3 query,
following referrals, and so forth).
The three bootstrapping models defined for use with this service
are the "targeted " model which is functionally identical to
traditional lookups for LDAP servers, the "top-down" model which
causes a client to submit a query to the root of a delegation
hierarchy, and a "bottom-up" model which causes a client to work
up through a delegation hierarchy until a server has been located.
5.2.1. Targeted query processing
The "targeted" model is similar to the traditional model of LDAP
lookups, in that a client queries a previously specified LDAP
server for a particular resource under the assumption that the
resource exists on that server. If the server or resource does not
exist (notwithstanding any referrals which may be returned), the
entire query fails.
The targeted model can be used when a fixed resource has been
specified (such as may occur with a URL), but can also be used if
the client prefers to use a "default" server for all operations.
The latter may occur when clients use proxy servers, caching
servers, or other fixed servers, in lieu of navigating the global
directory database with every query. In all of these cases,
however, failed lookups are considered to be fatal.
The steps for processing targeted queries are described below:
a. Determine the IP address and port number to be used (this
information may be determined from user input, a
configuration file, a URL, or from any other source).
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1. If a non-ASCII domain name has been specified for this
purpose, convert the domain name into its ASCII-
compatible form using the "ToASCII" process defined in
[RFC3490] before performing any lookups.
2. Locate the LDAP servers associated with the domain
name through the SRV query steps provided in section
5.2.4. If this step fails, use DNS lookups for A
resource records instead. If no resource records are
available, report the error to the user and exit.
b. Once a server has been determined, submit the search
operation. If the search operation fails, report the error
to the user and exit. Otherwise, display any answer data
which is returned.
c. If the answer data contains a subordinate reference
referral or a continuation reference referral, new query
processes MUST be spawned.
For subordinate reference referrals, process the URLs
according to the rules described in section 5.4 and restart
the query process at step 5.2.1.a. For each continuation
reference referral, display the answer data received so
far, process the LDAP URLs according to the rules described
in section 5.4 and start new query processes for each
referral at step 5.2.1.a, appending the output from these
searches to the current output.
Any additional subordinate reference referrals or
continuation reference referrals which are encountered from
any subsequent searches will need to be processed in the
same manner as specified above, until no additional
referrals are received.
d. Exit the query operation.
5.2.2. Top-down processing
The top-down model uses an input string to construct an LDAP
assertion value and search base, with DNS queries being used to
locate the LDAP servers associated with the appropriate top-level
delegation entity. Once this process completes, a query is issued
to the specified servers. This query may be subsequently
redirected to other servers through the use of LDAP referrals.
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The top-down model is primarily suited for locating Internet
resources which are centrally managed and delegated, and where
information about the delegation is desired. In particular, this
includes resources such as DNS domain names, IP address blocks,
and AS numbers.
Note that the top-down model does not use incrementally larger
domain names for the bootstrap process. Instead, it is assumed
that the root partition in the delegation tree will be able to
provide any necessary redirection services. For example, if the
domain name of "www.example.co.uk" is used in a query, the query
will be sent to the "dc=uk" partition, which should provide a
referral for the "dc=co,dc=uk" partition, which in turn should
provide a referral for the "dc=example,dc=co,dc=uk" partition.
The steps for processing top-down queries are described below:
a. Determine the directory partition for the query.
1. Separate the input string into discrete elements where
this is possible. For a DNS domain name of
"www.example.com", this would be "www", "example" and
"com". For the IPv4 network number of "192.0.2.14",
this would be "192", "0", "2" and "14". AS numbers
only have a single value and require no separation. Do
not discard the original query string.
2. IP addresses and AS numbers require additional
conversion. For IPv4 addresses, strip off the prefix
and convert the input string into a reverse-lookup DNS
domain name by reversing the order of the octets and
appending "in-addr.arpa" to the right of the domain
name. For IPv6 addresses, strip off the prefix and
reverse the nibble order of the address (where each
nibble is represented by a single hexadecimal
character), and append "ip6.arpa". For AS numbers,
append only the "arpa" domain name.
b. Form the LDAP search base for the query.
1. If the client application allows non-ASCII input,
convert the domain name formed in step 5.2.2.a above
into its ASCII-compatible form using the "ToASCII"
process defined in RFC 3490.
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2. Convert the right-most element from the domain name
formed in step 5.2.2.b.1 into a domainComponent DN
(such as "dc=com" or "dc=arpa"). This represents the
directory partition for the current query.
3. Append "cn=inetResources" to the front of the
domainComponent syntax ("cn=inetResources,dc=com").
This will form the fully-qualified search base for the
LDAP query.
c. Locate the LDAP servers associated with the resource by
processing the domain name formed in step 5.2.2.a above
through the SRV query steps provided in section 5.2.4.
d. If the SRV lookup succeeds:
1. Choose the best LDAP server, using the weighting
formula described in [RFC2782].
2. Formulate the LDAP search using the search base and
search filter constructed earlier. For example, if the
input query string was for "www.example.com", then the
client would begin the process by submitting an
inetDnsDomainMatch extensibleMatch search with the
assertion value of "www.example.com", and with a
search base of "dc=inetResources,dc=com". Similarly,
if the input query string was "192.0.2.14", then the
client would begin the process by submitting an
inetIpv4NetworkMatch extensibleMatch search with the
assertion value of "192.0.2.14/32", and with the
search base of "cn=inetResources,dc=arpa".
3. Submit the search operation to the chosen server and
port number. If the operation fails, report the
failure to the user and exit. Otherwise, display any
answer data which is returned.
4. If the answer data contains a subordinate reference
referral or a continuation reference referral, new
query processes MUST be spawned.
For subordinate reference referrals, process the URLs
according to the rules described in section 5.4 and
restart the query process at step 5.2.2.b. For each
continuation reference referral, display the answer
data received so far, process the LDAP URLs according
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to the rules described in section 5.4 and start new
query processes for each referral at step 5.2.2.b,
appending the output from these searches to the
current output.
Any additional subordinate reference referrals or
continuation reference referrals which are encountered
from any subsequent searches will need to be processed
in the same manner as specified above, until no
additional referrals are received.
e. If the SRV lookup fails (where failure is defined as any
DNS response message other than an answer), report the
failure to the user and exit the current search operation.
f. Exit the query operation.
5.2.3. Bottom-up processing
The bottom-up model uses an input string to construct an LDAP
assertion value and search base, with DNS queries being used to
locate the LDAP servers which are associated with the management
entity that is directly responsible for the resource in question.
If no servers are available for that partition, the parent
partition in the delegation hierarchy is used instead, with this
process repeating until a server has been located.
The bottom-up model is best used when a leaf-node partition needs
to be queried directly, either because there is no direct
delegation path for the resource in question, or because the user-
managed partition is preferable to the centralized delegation
information. For example, there is no global delegation body which
assigns and manages contact identifiers, so these identifiers need
to be directed towards the leaf-node partitions directly. The
bottom-up model can also be used for other kinds of resources if
desirable, although in most cases the bottom-down model will be
more useful for those resources.
The steps for processing bottom-up queries are described below:
a. Determine the input type (DNS Domain, IPv4 Address, etc.)
b. Determine the authoritative DNS domain for the resource.
1. Separate the input string into discrete elements where
this is possible. For a DNS domain name of
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"www.example.com", this would be "www", "example" and
"com". For the IPv4 network number of "192.0.2.14",
this would be "192", "0", "2" and "14". Do not discard
the original query string.
2. IP addresses require additional conversion. For IPv4
addresses, strip off the prefix and convert the input
string into a reverse-lookup DNS domain name by
reversing the order of the octets and appending
"in-addr.arpa" to the right of the resulting sequence.
For IPv6 addresses, strip off the prefix and reverse
the nibble order of the address (where each nibble is
represented by a single hexadecimal character), and
append "ip6.arpa" to the right of the resulting
sequence.
c. Form the LDAP search base for the query.
1. If the client application allows non-ASCII input,
convert the domain name formed in step 5.2.3.b above
into its ASCII-compatible form using the "ToASCII"
process defined in RFC 3490.
2. Convert the domain name formed in step 5.2.3.c.1 above
into a domainComponent DN (such as
"dc=www,dc=example,dc=com" or "dc=0,dc=2,dc=0,dc=192,
dc=in-addr,dc=arpa"). This represents the directory
partition for the current query.
3. Append the "cn=inetResources" RDN to the left of the
domainComponent syntax (perhaps resulting in
"cn=inetResources,dc=www,dc=example,dc=com"). This
will become the search base for the LDAP query.
d. Locate the LDAP servers associated with the resource by
processing the domain name formed in step 5.2.3.b above
through the SRV query steps provided in section 5.2.4.
e. If the SRV lookup fails with an NXDOMAIN response code (as
described in RFC 2308), then the domain name used for the
SRV lookup does not exist, and a substitute LDAP server and
search base must be used instead. This process involves
determining the parent zone for the domain name in
question, issuing an SRV lookup for that zone, and using
the domain name of the zone as the new LDAP search base,
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with this process repeating until a search base can be
located, or until a critical failure forces an exit.
1. Remove the left-most label from the domain name formed
in step 5.2.3.b.
2. If this process has already resulted in a query domain
name at a top-level domain such as "com" or "arpa",
convert the query domain name to "." (to signify the
root domain).
3. If the queried domain name is already set to ".", the
query can go no higher (this most likely indicates a
malformed DNS configuration, a connectivity problem,
or a typo in the query). Exit and report the failure
to the user.
4. Restart the process at step 5.2.2.b, using the domain
name formed above. Repeat until a server is located or
a critical failure forces an exit.
For example, if the original input string of
"www.example.com" resulted in a failed SRV lookup for
"_ldap._tcp.www.example.com", then the first fallback
SRV query would be for "_ldap._tcp.example.com", and
the next fallback query would be for "_ldap._tcp.com",
possibly being followed by "_ldap._tcp.", and possibly
resulting in failure after that.
f. If the SRV lookup succeeds:
1. Choose the best LDAP server, using the weighting
formula described in RFC 2782.
2. Formulate the LDAP search using the search base and
search filter constructed above. For example, if the
input query string was for "www.example.com", then the
client would begin the process by submitting an
inetDnsDomainMatch extensibleMatch search with the
assertion value of "www.example.com", with the search
base of "cn=inetResources,dc=www,dc=example,dc=com".
If the SRV lookups had failed (resulting in "com"
being used as the authoritative directory partition),
then the search base for the query would also be
trimmed accordingly ("cn=inetResources,dc=com").
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3. Submit the search operation to the chosen server and
port number. If the operation fails, report the
failure to the user and exit. Otherwise, display any
answer data which is returned.
4. If the answer data contains a subordinate reference
referral or a continuation reference referral, new
query processes MUST be spawned.
For subordinate reference referrals, process the URLs
according to the rules described in section 5.4 and
restart the query process at step 5.2.3.d. For each
continuation reference referral, display the answer
data received so far, process the LDAP URLs according
to the rules described in section 5.4 and start new
query processes for each referral at step 5.2.3.d,
appending the output from these searches to the
current output.
Any additional subordinate reference referrals or
continuation reference referrals which are encountered
from any subsequent queries will need to be processed
in the same manner as specified above, until no
additional referrals are received.
g. If a fatal DNS error condition occurs, report the error to
the user and stop processing the current query. A fatal DNS
error is any response message with an RCODE of FORMERR,
SERVFAIL, NOTIMPL, or REFUSED, or where a query results in
NODATA (implying that an "_ldap._tcp" domain name exists
but it doesn't have an SRV resource record associated with
it, which is most likely a configuration error).
h. Exit the query operation.
5.2.4. SRV processing
The bootstrapping models described in this document make use of
DNS SRV resource records to locate the LDAP servers associated
with the resource provided in the query input.
The procedure for constructing this SRV lookup is as follows:
a. Construct an SRV-specific label pair for the service type.
For LDAP queries, this will be "_ldap._tcp".
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b. If the client allows non-ASCII characters to be input, then
convert the domain name input into its ASCII-compatible
form by using the "ToASCII" process described in [RFC3490].
c. Append the SRV label pair to the left of the input domain
name from step 5.2.4.b. In the case of a query for the
"example.com" domain, this would result in an SRV-specific
domain name of "_ldap._tcp.example.com".
d. Issue a DNS query for the SRV resource records associated
with the domain name formed in step 5.2.4.b.
Multiple SRV resource records may be returned in response to a
query. Each resource record identifies a different connection
target, including the domain name of a server, and a port number
for that server. The port number specified in a SRV resource
record MUST be used for any subsequent bind and search operations.
SRV resource records provide "priority" and "weight" values which
MUST be used to determine the preferred server. If a server is
unavailable or unreachable, a connection attempt must be made to
the next-best server in the answer set.
Refer to [RFC2782] for a detailed explanation of SRV resource
records and their handling.
5.3. Query Processing
Once an authoritative server for the partition in question has
been located, the LDAP query can be submitted. In order to ensure
interoperability, this specification defines several behavioral
rules which clients and servers are encouraged to conform with.
These guidelines are discussed in the following sections.
5.3.1. Matching filters
LDAP search filters are fairly flexible, in that they allow for a
wide variety of configurable elements, such as the maximum number
of entries which are returned, the type of comparison operation
that needs to be performed, and other details. In order to ensure
interoperability, default values are defined here for many of
these elements.
[RFC2251] defines the LDAP search request specification, although
it does not provide guidelines or recommended values for the
filter settings. In an effort to promote interoperability among
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FIRS clients and servers, this document defines some recommended
and mandatory values for searches within the FIRS service.
NOTE: These rules ONLY apply to the FIRS search operations
in particular. Any queries for other resources SHOULD NOT
impose these restrictions. Also note that other documents
which define additional resource types can also define
different restrictions, and those definitions will take
precedence over the global defaults.
Servers MUST be prepared to enforce these rules independently of
the client settings, and clients MUST be prepared to receive
truncated search results accordingly.
The default values of an LDAPv3 search filter in FIRS are:
* Search base. The directory partition to be used in a search
will vary for each query operation. The methodology for
determining the current search base for a query is defined
by the query-processing protocols described in section 5.1,
although FIRS searches are normally constrained to the
"cn=inetResources" container of a particular directory
partition.
* Scope. In order to support continuation reference referrals
(which are defined as referral entries beneath a resource-
specific entry), clients MUST use a sub-tree scope for FIRS
searches. Servers MUST NOT arbitrarily limit the scope of
search operations.
* Dereference aliases. Although the FIRS service does not
make direct use of alias entries, they are not prohibited.
Clients SHOULD set the Dereference Aliases option to
"Always" for FIRS searches. Servers SHOULD dereference any
aliases which are encountered, where this is feasible (in
particular, where the alias refers to another directory
partition on the same server).
* Size limit. The size limit field specifies the maximum
number of entries that a server should return. For the FIRS
service, this setting SHOULD be set to a value between 25
and 100. This range ensures that the client is capable of
receiving a sufficient number of entries and continuation
references in a single response, but also works to prevent
runaway queries that match everything (such as searches for
"com", which can match every inetDnsDomain entry in the
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"cn=inetResources,dc=com" container). Servers MAY truncate
answer sets to 100 responses if the client specifies a
larger value.
* Time limit. The time limit field specifies the maximum
number of seconds that a server should process the search.
For the FIRS service, this setting SHOULD be set to a value
between 10 and 60 seconds. This range ensures that the
server is able to process a sufficient number of entries,
but also works to prevent runaway queries that match
everything. Servers MAY stop processing queries after 60
seconds if the client specifies a larger value.
* Types-only. The types-only setting is a Boolean flag which
controls whether or not attribute values are returned in
the answer sets. Since excessive queries are likely to be
more burdensome than larger answer sets, this setting
SHOULD be set to FALSE. Resource-constrained clients (such
as PDAs) MAY set this value to TRUE, but these clients MUST
be prepared to issue the necessary subsequent queries.
* Filter. The search operation will depend on the type of
data being queried. For FIRS queries, the filter MUST use
the matching rules defined for the relevant resource type.
* Attribute list. Clients MAY restrict the list of attributes
which are returned in searches, but are discouraged from
doing so without cause.
5.3.2. Query-volume restrictions
The restrictions listed in section 5.3.1 represent suggested
defaults, although server operators MAY impose any kinds of usage
limits they deem necessary or desirable.
Specifically, server operators MAY restrict the amount of
information provided to specific clients and/or users over a given
amount of time, within reason. For example, servers MAY restrict
clients to an arbitrary number of queries per hour, per day, and
so forth. Servers which refuse to process a query due volume
policy SHOULD reject the connection and/or query using the
"unwillingToPerform" response code ("53").
Clients MUST be prepared for connection requests and queries to be
denied for any reason, and MUST treat these conditions as non-
permanent failures. Clients MAY retry the operations if a known
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error condition is corrected (such as authentication errors), but
SHOULD NOT automatically generate retry attempts.
5.3.3. Authentication restrictions
Servers operators SHOULD allow anonymous authentication for read-
only access to public delegation data. Clients SHOULD use
anonymous authentication by default.
Wherever a server operator requires or desires clients to
authenticate for access, servers MUST support the simple
authentication mechanism defined in RFC 2222 [RFC2222], although
server operators MAY require the use of any authentication
mechanisms in addition to or instead of the simple mechanism.
Server operators SHOULD NOT impose unreasonable requirements for
proprietary authentication mechanisms for routine purposes.
Server operators MAY withhold privileged information from non-
privileged clients or users, as necessary.
Clients SHOULD NOT equate the absence of any attributes with the
absence of data, and SHOULD assume that the user is not authorized
to view any data which has not been provided.
5.3.4. Protocol and schema version controls
The FIRS collection of specifications are explicitly bound to the
LDAPv3 protocol, as defined by [RFC3377] and its subordinate
specifications. If a new version of the LDAP protocol emerges, it
is expected that some type of mechanism will be included for end-
points to use when negotiating over the version in use. Lacking
such a mechanism, FIRS is explicitly restricted to LDAPv3.
LDAP attributes, object classes, syntaxes and matching filters
have OIDs which uniquely identify the format of the data they
provide, and which act as simple schema-version identifiers in the
generic case. [RFC2251] defines standardized mechanisms for
retrieving and reading the OIDs associated with object classes and
attributes (among other resource types). These mechanisms MAY be
used whenever a FIRS client reads an entry, and MUST be used
whenever a FIRS client modifies or creates an entry (even though
FIRS does not define mechanisms for updating entries, it is
assumed that some clients will allow this behavior).
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Modifications to existing schema definitions MUST be accompanied
by OID changes.
5.4. Referral Processing
As was discussed in section 3.4, FIRS supports two types of
referrals, which are subordinate reference referrals and
continuation reference referrals. Both referral types use URLs for
the purpose of providing referral targets, using the rules
described in section 3.4 of this document.
Non-compliance with the requirements provided in section 3.4
amounts to an error, and is sufficient cause for a client to stop
processing a query.
As was discussed in section 3.4, subordinate reference referrals
are defined in [RFC3296], and use the SearchResultDone response
with a Referral result code as defined in [RFC2251]. Subordinate
reference referrals use a subset of the labeledURI syntax as
defined in [RFC2079], and use the syntax definitions from
[RFC2255] when LDAP URLs in particular are provided, although
section 3.4 of this document also defines additional restrictions
on the allowable URL syntax. This condition means that the current
search operation cannot proceed past this point, and the search
MUST be restarted. This will most often occur when the
inetResources entry for a partition has been redirected to another
directory partition.
Meanwhile, continuation reference referrals use the
SearchResultReference response, which is defined and described in
section 4.5.3 of [RFC2251]. Continuation reference referrals use a
subset of the labeledURI syntax as defined in [RFC2079], and use
the syntax definitions from [RFC2255] when LDAP URLs in particular
are to be provided, although section 3.4 of this document also
defines additional restrictions on the allowable URL syntax. This
condition means that the current search operation has partially
succeeded, but that additional searches SHOULD be started in order
for all of the answer data to be retrieved (in many cases, no
answer data will be provided, and in those situations, new queries
will be required for any data to be retrieved). This will occur
whenever the assertion value of a search has matched a resource
entry which is being managed by another directory partition, and
can occur with any of the search operations described in this
document.
The procedure for processing referral URLs is as follows:
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a. [RFC2251] allows multiple URLs to be provided, although the
URLs are not provided with any "preference" or "weighting"
values. If a set of URLs are provided, only one of the URLs
need to be tried (implementations MAY perform additional
queries in an attempt to recover from temporary failures,
although this is not required). Select one of the URLs at
random ("round-robin"), and continue to the next step in
the process.
b. Validate the protocol label. FIRS only supports the use of
the LDAP service type. URLs with other protocol identifiers
are to be treated as malformed.
c. Extract the port number provided with the URL, and set it
aside for use with the subsequent connection attempt. If no
port number has been provided in the URL, use the port
number discovered through any subsequent SRV lookups (as
described below), or as a last resort use the default port
number associated with the protocol identifier.
d. Determine the authoritative partition and search base
specified in the referral URL.
1. If no distinguished name element was provided, reuse
the existing authoritative partition and search base.
2. Otherwise, use the distinguished name element for the
search base of the subsequent search operation.
3. Extract the sequence of domainComponent distinguished
names from the search base, and use them as the
authoritative partition.
e. Determine the server address and port number specified in
the referral URL.
1. If a host identifier was not provided, map the
domainComponent elements determined in step 5.4.d to a
DNS domain name and submit a DNS lookup for the SRV
resource records associated with that domain name. If
this step fails, report the error to the user and exit
the query.
2. If the host identifier is an IP address, extract it
and skip to step 5.4.f.
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3. If no port number was provided in the URL, submit a
DNS lookup for the SRV resource records associated
with the domain name, as described in section 5.2.4.
If this lookup succeeds, skip to step 5.4.f.
4. If the SRV lookup from the previous step fails, or if
no port number was specified, submit a DNS lookup for
the A resource records.
f. Determine the new assertion value and/or matching filter
specified in the referral URL.
1. If the URL's path element does not contain a filter
element, reuse the current matching filter and
assertion value.
2. If the URL's path element contains a filter element,
use it to form the new matching filter and/or
assertion value.
g. Discard the remainder of the URL.
h. Use the discovered parameter values to start a new query.
For example, imagine that a referral has been received with the
URL value of "ldap:///cn=inetResources,dc=example,dc=com". The
processing rules for this URL would be as follows:
* Use "cn=inetResources,dc=example,dc=com" as the new search
base for the subsequent query.
* Use the domainComponent sequence of "dc=example,dc=com" as
the new authoritative partition.
* No host identifier was specified in the URL, so the
"dc=example,dc=com" partition must be used to seed a server
identifier of "example.com".
* Issue DNS lookups for the SRV resource records associated
with "_ldap._tcp.example.com" to determine the server and
port number for the subsequent query.
* Reuse the existing assertion value and matching filter.
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As another example, imagine a referral with the URL value of
"ldap://example.com/cn=inetResources,dc=example,dc=com". The
processing rules for this URL would be as follows:
* Use "cn=inetResources,dc=example,dc=com" as the new search
base for the subsequent query.
* Use the domainComponent sequence of "dc=example,dc=com" as
the new authoritative partition.
* Use the host identifier of "example.com" as specified in
the URL.
* Issue DNS lookups for the SRV resource records associated
with "_ldap._tcp.example.com" to determine the server and
port number for the subsequent query.
* Reuse the existing assertion value and matching filter.
As another example, imagine a referral with the URL value of
"ldap:////???(cn:dn:www.example.com). The processing rules for
this URL would be as follows:
* Reuse the existing search base and authoritative partition
information.
* Reuse the existing server and port number.
* Use "(cn:dn:www.example.com)" as the new matching filter
and assertion value.
Note that step 5.4.g requires the client to discard the remainder
of the URL, although this step may be changed in subsequent
versions of this specification. In particular, [CRISP-REQ]
requires the ability to pass an inter-server "referral bag", and
this mechanism may be implemented through the use of extensions in
the LDAP URL.
6. Security Considerations
Security considerations are discussed in [FIRS-ARCH].
7. IANA Considerations
IANA considerations are discussed in [FIRS-ARCH].
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8. Author's Addresses
Eric A. Hall
ehall@ehsco.com
9. Normative References
[RFC1274] Barker, P., and Kille, S. "The COSINE and
Internet X.500 Schema", RFC 1274, November
1991.
[RFC2079] Smith, M. "Definition of an X.500 Attribute
Type and an Object Class to Hold Uniform
Resource Identifiers (URIs)", RFC 2079,
January 1997.
[RFC2222] Myers, J. "Simple Authentication and Security
Layer (SASL)", RFC 2222, October 1997.
[RFC2247] Kille, S., Wahl, M., Grimstad, A., Huber, R.,
and Sataluri, S. "Using Domains in LDAP/X.500
DNs", RFC 2247, January 1998.
[RFC2251] Wahl, M., Howes, T., and Kille, S.
"Lightweight Directory Access Protocol (v3)",
RFC 2251, December 1997.
[RFC2252] Wahl, M., Coulbeck, A., Howes, T., and Kille,
S. "Lightweight Directory Access Protocol
(v3): Attribute Syntax Definitions", RFC 2252,
December 1997.
[RFC2253] Wahl, M., Kille, S., and Howes, T.
"Lightweight Directory Access Protocol (v3):
UTF-8 String Representation of DNs", RFC 2253,
December 1997.
[RFC2254] Howes, T. "The String Representation of LDAP
Search Filters", RFC 2254, December 1997.
[RFC2255] Howes, T., and Smith, M. "The LDAP URL
Format", RFC 2255, December 1997.
[RFC2256] Wahl, M. "A Summary of the X.500(96) User
Schema for use with LDAPv3", RFC 2256,
December 1997.
[RFC2277] Alvestrand, H. "IETF Policy on Character Sets
and Languages", BCP 18, RFC 2277, January
1998.
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[RFC2308] Andrews, M. "Negative Caching of DNS Queries
(DNS NCACHE)", RFC 2308, March 1998.
[RFC2596] Wahl, M., and Howes, T. "Use of Language Codes
in LDAP", RFC 2596, May 1999.
[RFC2782] Gulbrandsen, A., Vixie, P., and Esibov, L. "A
DNS RR for specifying the location of services
(DNS SRV)", RFC 2782, February 2000.
[RFC2798] Smith, M. "Definition of the inetOrgPerson
LDAP Object Class", RFC 2798, April 2000.
[RFC3296] Zeilenga, K. "Named Subordinate References in
Lightweight Directory Access Protocol (LDAP)
Directories", RFC 3296, July 2002.
[RFC3377] Hodges, J., and Morgan, R. "Lightweight
Directory Access Protocol (v3): Technical
Specification", RFC 3377, September 2002.
[RFC3490] Faltstrom, P., Hoffman, P., and Costello, A.
"Internationalizing Domain Names in
Applications (IDNA)", RFC 3490, March 2003.
[FIRS-ARCH] Hall, E. "The Federated Internet Registry
Service: Architecture and Implementation
Guide", draft-ietf-crisp-firs-arch-01, May
2003.
[FIRS-ASN] Hall, E. "Defining and Locating Autonomous
System Numbers in the Federated Internet
Registry Service", draft-ietf-crisp-firs-asn-
01, May 2003.
[FIRS-CONTCT] Hall, E. "Defining and Locating Contact
Persons in the Federated Internet Registry
Service", draft-ietf-crisp-firs-contact-01,
May 2003.
[FIRS-CORE] Hall, E. "The Federated Internet Registry
Service: Core Elements", draft-ietf-crisp-
firs-core-01, May 2003.
[FIRS-DNS] Hall, E. "Defining and Locating DNS Domains in
the Federated Internet Registry Service",
draft-ietf-crisp-firs-dns-01, May 2003.
[FIRS-DNSRR] Hall, E. "Defining and Locating DNS Resource
Records in the Federated Internet Registry
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Service", draft-ietf-crisp-firs-dnsrr-01, May
2003.
[FIRS-IPV4] Hall, E. "Defining and Locating IPv4 Address
Blocks in the Federated Internet Registry
Service", draft-ietf-crisp-firs-ipv4-01, May
2003.
[FIRS-IPV6] Hall, E. "Defining and Locating IPv6 Address
Blocks in the Federated Internet Registry
Service", draft-ietf-crisp-firs-ipv6-01, May
2003.
[US-ASCII] Cerf, V. "ASCII format for Network
Interchange", RFC 20, October 1969.
10. Acknowledgments
Funding for the RFC editor function is currently provided by the
Internet Society.
Portions of this document were funded by Verisign Labs.
The first version of this specification was co-authored by Andrew
Newton of Verisign Labs, and subsequent versions continue to be
developed with his active participation.
11. Changes from Previous Versions
draft-ietf-crisp-firs-core-01:
* Several clarifications and corrections have been made.
* Significant portions of text were moved to [FIRS-ARCH].
draft-ietf-crisp-firs-core-00:
* Restructured document set, separating the architectural
discussion from the technical descriptions. Several
sections were relocated to [FIRS-ARCH] as a result of this
change.
* "Attribute references" have been eliminated from the
specification. All referential attributes now provide
actual data instead of URL pointers to data. Clients that
wish to retrieve these values will need to start new
queries using the data values instead of URLs.
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* The various modified* operational attributes in the core
schema have been eliminated as unnecessary.
* Several attributes had their OIDs changed. NOTE THAT THIS
IS AN INTERNET DRAFT, AND THAT THE OIDS ARE SUBJECT TO
ADDITIONAL CHANGES AS THIS DOCUMENT IS EDITED.
draft-ietf-crisp-lw-core-00:
* As a result of the formation of the CRISP working group,
the original monolithic document has been broken into
multiple documents, with draft-ietf-crisp-lw-core
describing the core service, while related documents
describe the per-resource schema and access mechanisms.
* References to the ldaps: URL scheme have been removed,
since there is no standards-track specification for the
ldaps: scheme.
* An acknowledgements section was added.
draft-hall-ldap-whois-01:
* The “Objectives” section has been removed. [ir-dir-req] is
now being used as the guiding document for this service.
* Several typographical errors have been fixed.
* Some unnecessary text has been removed.
* Figures changed to show complete sets of object classes, to
improve inheritance visibility.
* Clarified the handling of reverse-lookup domains (zones
within the in-addr.arpa portion of the DNS hierarchy) in
the inetDnsDomain object class reference text.
* Referrals now use regular LDAP URLs (multiple responses
with explicit hostnames and port numbers). Prior editions
of this specification used LDAP SRV resource records for
all referrals.
* The delegation status codes used by the
inetDnsDelegationStatus, inetIpv4DelegationStatus,
inetIpv6DelegationStatus and inetAsnDelegationStatus
attributes have been condensed to a more logical set.
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* Added an inetDnsAuthServers attribute for publishing the
authoritative DNS servers associated with a domain. NOTE
THAT THIS IS A TEMPORARY ATTRIBUTE THAT WILL EVENTUALLY BE
REPLACED BY GENERALIZED RESOURCE-RECORD ENTRIES AND
ATTRIBUTES.
* Added an inetGeneralDisclaimer attribute for publishing
generalized disclaimers.
* Added the inetAssociatedResources auxiliary object class
for defining associated resources, and moved some of the IP
addressing and ASN attributes to the new object class.
* Several attributes had their OIDs changed. NOTE THAT THIS
IS AN INTERNET DRAFT, AND THAT THE OIDS ARE SUBJECT TO
ADDITIONAL CHANGES AS THIS DOCUMENT IS EDITED.
12. Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished
to others, and derivative works that comment on or otherwise
explain it or assist in its implementation may be prepared,
copied, published and distributed, in whole or in part, without
restriction of any kind, provided that the above copyright notice
and this paragraph are included on all such copies and derivative
works. However, this document itself may not be modified in any
way, such as by removing the copyright notice or references to the
Internet Society or other Internet organizations, except as needed
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process must be followed, or as required to translate it into
languages other than English.
The limited permissions granted above are perpetual and will not
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This document and the information contained herein is provided on
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ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR
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