Internet DRAFT - draft-ietf-scim-use-cases
draft-ietf-scim-use-cases
SCIM WG K. LI, Ed.
Internet-Draft Alibaba Group
Intended status: Informational P. Hunt
Expires: November 8, 2015 Oracle
B. Khasnabish
ZTE (TX) Inc.
A. Nadalin
Microsoft
Z. Zeltsan
Individual
May 7, 2015
SCIM Definitions, Overview, Concepts and Requirements
draft-ietf-scim-use-cases-08
Abstract
This document provides definitions and an overview of the System for
Cross-domain Identity Management (SCIM). It lays out the system's
concepts, models and flows, and includes user scenarios, use cases,
and requirements.
Status of this Memo
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This Internet-Draft will expire on November 8, 2015.
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. SCIM User Scenarios . . . . . . . . . . . . . . . . . . . . . 4
2.1. Background & Context . . . . . . . . . . . . . . . . . . . 4
2.2. Model Concepts . . . . . . . . . . . . . . . . . . . . . . 4
2.2.1. Triggers . . . . . . . . . . . . . . . . . . . . . . . 4
2.2.2. Actors . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.3. Modes & Flows . . . . . . . . . . . . . . . . . . . . 6
2.2.4. Bulk & Batch Operational Semantics . . . . . . . . . . 7
2.3. Cloud Service Provider to Cloud Service Provider Flows
(CSP->CSP) . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3.1. CSP->CSP - Create Identity (Push) . . . . . . . . . . 7
2.3.2. CSP->CSP - Update Identity (Push) . . . . . . . . . . 7
2.3.3. CSP->CSP - Delete Identity (Push) . . . . . . . . . . 8
2.3.4. CSP->CSP - SSO Trigger (Push) . . . . . . . . . . . . 8
2.3.5. CSP->CSP - SSO Trigger (Pull) . . . . . . . . . . . . 8
2.3.6. CSP->CSP - Password Reset (Push) . . . . . . . . . . . 9
2.4. Enterprise Cloud Subscriber to Cloud Service Provider
Flows(ECS->CSP) . . . . . . . . . . . . . . . . . . . . . 9
2.4.1. ECS->CSP - Create Identity (Push) . . . . . . . . . . 9
2.4.2. ECS ->CSP - Update Identity (Push) . . . . . . . . . . 9
2.4.3. ECS ->CSP - Delete Identity (Push) . . . . . . . . . . 10
2.4.4. ECS ->CSP - SSO Pull . . . . . . . . . . . . . . . . . 10
3. SCIM Use Cases . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1. Migration of the identities . . . . . . . . . . . . . . . 10
3.2. Single Sign-On (SSO) Service . . . . . . . . . . . . . . . 11
3.3. Provisioning of the user accounts for a Community of
Interest (CoI) . . . . . . . . . . . . . . . . . . . . . . 13
3.4. Transfer of attributes to a relying party web site . . . . 14
3.5. Change notification . . . . . . . . . . . . . . . . . . . 15
4. Security considerations . . . . . . . . . . . . . . . . . . . 16
5. IANA considerations . . . . . . . . . . . . . . . . . . . . . 17
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.1. Normative References . . . . . . . . . . . . . . . . . . . 17
7.2. Informative References . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
This document provides the SCIM definitions, overview, concepts,
flows, scenarios and use cases. It also provides a list of the
requirements derived from the use cases.
The document's objective is to help with understanding of the design
and applicability of SCIM schema [I-D.ietf-scim-core-schema] and SCIM
protocol [I-D.ietf-scim-api].
Unlike the practice of some protocols like ABFAB and SAML2 WebSSO,
SCIM provides provisioning and de-provisioning of resources in a
separate context from authentication (aka just-in-time provisioning).
1.1. Terminology
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 [RFC2119] when they
appear in ALL CAPS. These words may also appear in this document in
lower case as plain English words, absent their normative meanings.
Here is a list of acronyms and abbreviations used in this document:
o COI: Community Of Interest
o CRM: Customer Relationship Management
o CRUD: Create Read Update Delete
o CSP: Cloud Service Provider
o CSU: Cloud Service User
o ECS: Enterprise Cloud Subscriber
o IaaS: Infrastructure as a Service
o JIT: Just In Time
o PaaS: Platform as a Service
o SaaS: Software as a Service
o SAML: Security Assertion Markup Language
o SCIM: System for Cross-domain Identity Management
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o SSO: Single-Sign On
2. SCIM User Scenarios
2.1. Background & Context
The System for Cross-domain Identity Management (SCIM) specification
is designed to manage user identity in cloud based applications and
services in a standardized way to enable interoperability, security
and scalability. The specification suite seeks to build upon
experience with existing schemas and deployments, placing specific
emphasis on simplicity of development and integration, while applying
existing authentication, authorization, and privacy models. The
intent of SCIM specification is to reduce the cost and complexity of
user management operations by providing a common user schema and
extension model, as well as binding documents to provide patterns for
exchanging this schema using standard protocols. In essence, make it
fast, cheap, and easy to move users in to, out of, and around the
cloud.
The SCIM scenarios are overview user stories designed to help clarify
the intended scope of the SCIM effort.
2.2. Model Concepts
2.2.1. Triggers
Quite simply, triggers are actions or activities that start SCIM
flows. Triggers may not be relevant at the protocol or the schema,
they really serve to help identify the type or activity that resulted
in a SCIM protocol exchange. Triggers make use of the traditional
provisioning CRUD (Create Read Update & Delete) operations but add
additional use case contexts like "SSO" (Single-Sign On) as it is
designed to capture a class of use case that makes sense to the actor
requesting it rather than to describe a protocol operation.
o Create SCIM Identity Resource - Service On-boarding Trigger: A
"create SCIM identity resource" trigger is a service on-boarding
activity in which a business action such as a new hire or new
service subscription is initiated by one of the SCIM Actors. In
the protocol itself, service on-boarding may well be implemented
via the same resource PUT method as a service change. This is
particular to the implementation, and not to the use cases that
drive that implementation.
o Update SCIM Identity Resource - Service Change Trigger: An "update
SCIM identity resource" trigger is a service change activity as a
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result of an identity moving or changing its service level. An
"update SCIM identity" trigger might be the result of a change in
a service subscription level or a change to key identity data used
to denote a service subscription level. Password changes are
specifically called out from other more general identity attribute
changes as they are considered to have specific use case
differences.
o Delete SCIM Identity Resource - Service Termination Trigger: A
"delete SCIM identity resource" trigger represents a specific and
deliberate action to remove an identity from a given SCIM service
point. At this stage it is unclear if the SCIM protocol needs to
identify separate protocol exchange for a service suspension
actions. This may be relevant as target services usually
differentiate between these result and may require separate
resource representations as a result.
o Single-Sign On (SSO) Trigger - Service Access Request: A "Single-
Sign On" trigger is a special class of activity in which a Create
or Update trigger is initiated during an SSO operational flow.
The implication here is that as the result of a service access
request by the end user (SSO), defined SCIM protocol exchanges can
be used to initiate SCIM resource CRUD somewhere in the service
cloud.
2.2.2. Actors
Actors are the operating parties that take part in both sides of a
SCIM protocol exchange, and help identify the source of a given
Trigger. So far, we have identified the following SCIM Actors:
o Cloud Service Provider (CSP): A CSP is the entity operating a
given cloud service. In a SaaS scenario this is simply the
application provider. In an IaaS or PaaS scenario, the CSP may be
the underlying IaaS/PaaS infrastructure provider or the owner of
the application running on that platform. In all cases, the CSP
is the thing that holds the identity information being operated
upon. Put another way, the CSP really is the service that the
end-end user interacts with.
o Enterprise Cloud Subscriber (ECS): An ECS represents a middle-tier
of aggregation for related identity records. In one of our sample
enterprise SaaS scenarios, the ECS is "Example.com" that
subscribes to a cloud based CRM service service "SaaS-CRM.Inc"
(the CSP) for all of its sales staff. The actual Cloud Service
Users (CSUs) are the FooBar.Inc. sales staff. The ECS actor is
identified to help capture use cases in which a single entity is
given administrative responsibility for other identity accounts.
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SCIM may not address the configuration and setup of an ECS within
the CSP, but it does address use cases in which SCIM identity
resources are grouped together and administers as part of some
broader agreement or operational exchange.
o Cloud Service User (CSU): A CSU represents the real cloud service
end user - the "person logging into and using the cloud service".
As described above, and ECS will typically own or manage multiple
CSU identities where as the CSU represents the FooBar.Inc.
employee using the cloud service to manage their CRM process.
+---------------------+
| Cloud Service |
| Provider (CSP) |
+---------------------+
|
+--------------------------------+
| |
v v
+----------------+ +----------------+
|Enterprise Cloud| |Enterprise Cloud|
|Subscriber (ECS)| |Subscriber (ECS |
+----------------+ +----------------+
| |
+----------------+ +----------------+
| | | |
v v v v
+-------------+ +-------------+ +-------------+ +-------------+
|Cloud Service| |Cloud Service| |Cloud Service| |Cloud Service|
| User (CSU) | | User (CSU) | | User (CSU) | | User (CSU) |
+-------------+ +-------------+ +-------------+ +-------------+
Figure 1: SCIM Actors
2.2.3. Modes & Flows
Modes identify the functional intent of a data-flow initiated in a
SCIM scenario. The modes identified so far are 'push' and 'pull'
referring to the fact of pushing data to, or pulling data from an
authoritative identity data store.
In the SCIM scenarios, Modes are often used in the context of a flow
between two Actors. For example, one might refer to a Cloud-to-Cloud
Pull exchange. Here one Cloud Service Provider (CSP) is pulling
identity information from another CSP. Commonly referenced flows
are:
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o Cloud Service Provider to Cloud Service Provider (CSP->CSP)
o Enterprise Cloud Subscriber to Cloud Service Provider (ECS-CSP)
Modes & flows simply help us understand what is taking place; they
are likely to be technically meaningless at the protocol level, but
again they help the reader follow the SCIM scenarios and apply them
to real world use cases.
2.2.4. Bulk & Batch Operational Semantics
It is assumed that each of the triggers action outlined in this
document may be part of the larger bulk or batch operation.
Individual SCIM actions should be able to be collected together to
create single protocol exchanges.
The initial focus of SCIM scenarios is on identifying base flows and
single operations. The specific complexity of full bulk and batch
operations is left to a later version of the scenarios or to the main
specification.
2.3. Cloud Service Provider to Cloud Service Provider Flows (CSP->CSP)
These scenarios represent flows between two Cloud Service Providers
(CSPs). It is assumed that each CSP maintains an Identity Data Store
for its Cloud Service Users (CSUs). These scenarios address various
joiner, mover, leaver and JIT triggers, resulting in push and pull
data exchanges between the CSPs.
2.3.1. CSP->CSP - Create Identity (Push)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. CSP-1 receives a Create Identity trigger action from
its Enterprise Cloud Subscriber (ECS-1). CSP-1 creates a local user
account for the new CSU. CSP-1 then pushes the new CSU joiner push
request down-stream to CSU-2 and gets confirmation that the account
was successfully created. After receiving the confirmation from
CSP-2, CSP-1 sends an acknowledgement to the requesting ECS.
2.3.2. CSP->CSP - Update Identity (Push)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. The Enterprise Cloud Subscriber (ECS-1) has already
created an account with CSP-1 and supplied a critical attribute
"department" that is used by CSP-1 to drive service options. CSP-1
then receives an Update Identity trigger action from its Enterprise
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Cloud Subscriber (ECS). CSP-1 updates its local directory account
with the new department value. CSP-1 then initiates a separate SCIM
protocol exchange to push the mover change request down-stream to
CSP-2. After receiving the confirmation from CSP-2, CSP-1 sends an
acknowledgment to ECS-1.
2.3.3. CSP->CSP - Delete Identity (Push)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. CSP-1 receives a Delete Identity trigger action from
its Enterprise Cloud Subscriber (ECS-1). CSP-1 suspends the local
directory account for the specified CSU account. CSP-1 then pushes a
termination request for the specified CSU account down-stream to
CSP-2 and gets confirmation that the account was successfully
removed. After receiving the confirmation from CSP-2, CSP-1
finalizes the deletion operation and sends an acknowledgment to the
requesting ECS.
This use case highlights how different CSPs may implement different
operational semantics behind the same SCIM operation. Note CSP-1
suspends the account representation for its service where as CPS-2
implements a true delete operation.
2.3.4. CSP->CSP - SSO Trigger (Push)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. However, rather than pre-provisioning accounts from
CSP-1 to CSP-2, CSP-1 waits for a service access request from the end
Cloud Service User (CSU-1) before issuing account creation details to
CSP-2. When the CSU completes a SSO transaction from CSP-1 to CSP-2,
CSP-2 then creates an account for the CSU based on information pushed
to it from CSP-1.
At the protocol level, this class of scenarios may result in the use
of common protocol exchange patterns between CSP-1 & CSP-2.
2.3.5. CSP->CSP - SSO Trigger (Pull)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. However, rather than pre-provisioning accounts from
CSP-1 to CSP-2, CSP-2 waits for a service access request from the
Cloud Service User (CSU-1) before initiating a Pull request to gather
information about the CSU sufficient to create a local account.
At the protocol level, this class of scenarios may result in the use
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of common protocol exchange patterns between CSP-2 & CSP-1.
2.3.6. CSP->CSP - Password Reset (Push)
In this scenario two CSPs (CSP-1 & CSP-2) have a shared service
agreement in place that requires the exchange of Cloud Service User
(CSU) accounts. CSP-1 wants to change the password for a specific
Cloud Service User (CSU-1). CSP-1 sends a request to CSP-2 to reset
the password value for CSU-1.
At the protocol level, this scenario may result in the same protocol
exchange as any other attribute change request.
2.4. Enterprise Cloud Subscriber to Cloud Service Provider
Flows(ECS->CSP)
These scenarios represent flows between an Enterprise Cloud
Subscriber (ECS) and a Cloud Service Providers (CSP). It is assumed
that both the ECS and the CSP maintains an information access service
for the relevant Cloud Service Users (CSUs). These scenarios address
various joiner, mover, leaver and JIT triggers, resulting in push and
pull data exchanges between the ECS and the CSP.
Many of these scenarios are very similar to those defined in the
Cloud Service Provider to Cloud Service Provider section above. They
are identified separately here so that we may explore any differences
and might emerge.
2.4.1. ECS->CSP - Create Identity (Push)
In this scenario an Enterprise Cloud Subscriber (ECS-1) maintains a
service with a Cloud Service Provider (CSP-1) that requires the
sharing of various Cloud Service User (CSU) accounts. A new user
joins ECS-1 and so ECS-1 pushes an account creation request to CSP-1,
supplying all required base SCIM schema attribute values and
additional extended SCIM schema values as required.
2.4.2. ECS ->CSP - Update Identity (Push)
In this scenario an Enterprise Cloud Subscriber (ECS-1) maintains a
service with Cloud Service Provider (CSP-1) that drives service
definition from a key account schema attribute called Department.
ECS-1 wishes to move a given CSU from Department A to Department B
and so it pushes an attribute update request to the CSP.
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2.4.3. ECS ->CSP - Delete Identity (Push)
In this scenario an Enterprise Cloud Subscriber (ECS-1) maintains a
service with a Cloud Service Provider (CSP-1). Upon termination of
one of its employees' employment agreement, ECS-1 sends a suspend
account request to CSP-1 (Figure 1.4.3-1). One week later the ECS
wishes to complete the process by fully removing the Cloud Service
User (CSU) account and so it sends a terminate account request to
CSP-1.
2.4.4. ECS ->CSP - SSO Pull
In this scenario an Enterprise Cloud Subscriber (ECS-1) maintains a
service with a Cloud Service Provider (CSP-1). No accounts are
created or exchanged in advance. However, rather than pre-
provisioning accounts from ECS-1 to CSP-1, CSP-1 waits for a service
access request from the Cloud Service User (CSU-1) under the control
domain of ECS-1, before issuing an account Pull request to ECS-1.
3. SCIM Use Cases
This section lists the SCIM use cases.
3.1. Migration of the identities
Description:
A company SomeEnterprise runs an application ManageThem that relies
on the identity information about its employees (e.g., identifiers,
attributes). The identity information is stored at the cloud
provided by SomeCSP. SomeEnterprise has decided to move identity
information to the cloud of a different provider - AnotherCSP. In
addition, SomeEnterprise has purchased a second application
ManageThemMore, which also relies on the identity information.
SomeEnterprise is able to move identity information to AnotherCSP
without changing the format of identity information. The application
ManageThemMore is able to use the identity information.
Pre-conditions:
o SomeCSP is a cloud service provider for SomeEnterprise.
o SomeCSP has a known attribute name and value for the Enterprise
used for managing and transferring data.
o AnotherCSP is a new cloud service provider for SomeEnterprise.
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o All involved cloud service providers and applications support the
same standard specifying the format for and actions on the user
(e.g., employee) identity information.
Post-conditions:
o SomeEnterprise has moved its employees' identity information from
SomeCSP to AnotherCSP without making any changes to representation
of identity information.
o Application ManageThemMore is able to use the identity
information.
Requirements:
o SomeEnterprise, the applications ManageThem and ManageThemMore,
the providers SomeCSP and AnotherCSP support a common standard for
identity information, which specifies the following:
* Format (or schema) for representing user identity information
* Interfaces and protocol for managing user identity information
o Cloud providers shall be able to meet regulatory requirements when
migrating identity information between jurisdictional regions
(countries, state-by-state for regulations on privacy).
o Cloud providers shall be able to log all actions related to
SomeEnterprise employees' identities.
o The logs should be secure and available for auditing.
3.2. Single Sign-On (SSO) Service
Description:
Bob has an account with application hosted by a cloud service
provider SomeCSP. SomeCSP has federated its user identities with a
cloud service provider AnotherCSP. Bob requests a service from an
application running on AnotherCSP. The application running on
AnotherCSP, relying on Bob's authentication by SomeCSP and using
identity information provided by SomeCSP, serves Bob's request.
Pre-conditions:
o Bob's identity information is stored on SomeCSP.
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o SomeCSP and AnotherCSP have established trust and federated their
user identities.
o SomeCSP is able to authenticate Bob.
o SomeCSP is able to securely provide the authentication results to
AnotherCSP.
o SomeCSP is able to securely provide Bob's identity information
(e.g., attributes) to AnotherCSP.
o AnotherCSP is able to verify information provided by SomeCSP.
o SomeCSP is able to process the identity information received from
AnotherCSP.
Post-conditions:
Bob has received the requested service from an application running on
AnotherCSP without having to authenticate to that application
explicitly.
Requirements:
o Bob must have an account with SomeCSP.
o SomeCSP and AnotherCSP must establish trust and federate their
user identities.
o SomeCSP must be able to authenticate Bob.
o SomeCSP must be able to securely provide the authentication
results to AnotherCSP.
o SomeCSP must be able to securely provide Bob's identity
information (e.g., attributes) to AnotherCSP.
o AnotherCSP must be able to verify the identity information
provided by SomeCSP.
o SomeCSP must be able to process the identity information received
from AnotherCSP.
o SomeCSP and AnotherCSP must log information generated by Bob's
actions according to their policies and the trust agreement
between them.
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3.3. Provisioning of the user accounts for a Community of Interest
(CoI)
Description:
Organization YourHR provides Human Resources (HR) services to a
Community of Interest (CoI) YourCoI. The HR services are offered as
Software-as-a-Service (SaaS) on public and private clouds. YourCoI's
offices are located all over the world. Their Information Technology
(IT) systems may be composed of the combinations of the applications
running on Private and Public clouds along with the traditional IT
systems. The local YourCoI offices are responsible for collecting
personal information(i.e. user identities and attributes). YourHR
services provide means for provisioning and distributing the employee
identity information across all YourCoI offices. YourHR also enables
the individual users (e.g., employees) to manage their personal
information that they are responsible for (e.g., update of an address
or a telephone number).
Pre-conditions:
o YourCoI has a complex infrastructure composed of the large number
of local offices that rely on the diverse IT systems.
o YourCoI has contracted YourHR to provide the HR services.
o Each local office has a right to establish a personal account for
an employee.
Post-conditions:
o All personal accounts are globally available to any authorized
user or application across the YourCoI system through the services
provided by YourHR.
o The employees have ability to manage the part of personal
information that is in their responsibility.
Requirements:
o Your HR must ensure that information generated by the local
offices is provisioned securely and considers privacy requirements
in a timely fashion across systems that may span technical (e.g.,
protocols and applications), administrative (e.g., corporate),
regulatory (e.g. location) and jurisdictional domains.
o Management of personal information must be protected against
unauthorized access, eavesdropping, and should be distributed only
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to authorized parties and services.
o Regulatory requirements shall be met when migrating identity
information between jurisdictional regions (countries, state-by-
state for regulations on privacy).
o All operation with identity data must be securely logged.
o The logs should be available for auditing.
3.4. Transfer of attributes to a relying party web site
Description:
An end user has an account in a directory service A with one or more
attributes. That user then visits relying party web site B, and the
web site B requires attributes of the user. The user selectes some
attributes and authorizes the transfer of data via authorization
protocols (e.g. OAuth, SAML), so selected attributes of the user are
transferred from the user's account in directory service A to the web
site B at the time of the user's first visit to that site.
Pre-conditions:
o User has an account in a directory service A.
o User has one or more attributes.
o User visits web site of a relying party B.
Post-conditions:
Selected attributes of the user are transferred from the user's
account in directory service A to the web site B at the time of the
user's first visit to that site.
Requirements:
o Relying party B must be able to authenticate the end user.
o Relying party B must be able to securely provide the
authentication results to directory service A.
o Directory service A must be able to securely provide end user's
identity information (e.g., attributes) to relying party B.
o Regulatory requirements shall be met when migrating identity
information between jurisdictional regions (countries, state-by-
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state for regulations on privacy).
o Relying parties have to be aware of changes to their cached copy,
as these would potentially cause a state change in other relying
parties.
o A maximum period should be set for the relying party to cache the
information.
3.5. Change notification
Description:
An end user has an account in a directory service A with one or more
attributes. That user then visits relying party web site B. Relying
party web site B queries directory service A for attributes
associated with that user, and related resources.
The attributes of the user change later in directory service A. For
example, the attributes might change if the user changes their name,
has their account disabled, or terminates their relationship with
directory service A. Furthermore, other resources and their
attributes might also change. The directory service A then wishes to
notify relying party web site B of these changes, as relying party B
might (or might not) have a cache of those attributes, and if the
relying party B were aware of these changes to their cached copy,
would potentially cause a state change in relying party B.
The volume of changes, however, might be substantial, and only some
of the changes may be of interest to relying party B, so directory
service A does not wish to "push" all the changes to B. Instead,
directory service A wishes to notify B that there are changes
potentially of interest, such that B can at an appropriate time
subsequently contact directory service A and retrieve just the subset
of changes of interest to B.
Note that the user must authorize the directory service A to transfer
data to the web site, and the user must authorize the directory
service A to notify the web site.
Pre-conditions:
o User has an account in a directory service A.
o User has one or more attributes.
o User visits relying party web site B.
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o The resource being updated is at the web site.
Post-conditions:
Directory service A is able to notify relying party B that there are
changes potentially of interest.
Requirements:
o Relying party B must be able to authenticate the end user.
o Relying party B must be able to securely provide the
authentication results to directory service A.
o Directory service A must be able to securely provide end user's
changed identity information (e.g., attributes) to relying party
B.
o Relying party B must be able at an appropriate time to
subsequently contact directory service A and retrieve just the
subset of changes of interest to relying party B.
4. Security considerations
Authentication and authorization must be guaranteed for the SCIM
operations, to ensure that only authenticated entities can perform
the SCIM requests and the requested SCIM operations are authorized.
SCIM resources (e.g., Users and Groups) can contain sensitive
information. Thus, data confidentiality MUST be guaranteed at the
transport layer.
There can be privacy issues that go beyond transport security, e.g.
moving PII offshore between CSPs. Regulatory requirements shall be
met when migrating identity information between jurisdictional
regions (countries, state-by-state for regulations on privacy.
Additionally, privacy sensitive data elements may be omitted or
obscured in SCIM transactions or stored records to protect these data
elements for a user. For instance a role based identifier might be
used in place of an individual's name.
Detailed security considerations are specified in section 7 of SCIM
protocol [I-D.ietf-scim-api] and section 9 of SCIM schema
[I-D.ietf-scim-core-schema].
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5. IANA considerations
This Internet Draft includes no request to IANA.
6. Acknowledgements
Authors would like to thank Ray Counterman, Richard Fiekowsky, Bert
Greevenbosch, Barry Leiba, Kelly Grizzle, Magnus Nystrom, Stephen
Farrell, Kathleen Moriarty, Benoit Claise, Dapeng Liu and Jun Li for
their reviews and comments.
Also thanks to Darran Rolls and Patrick Harding, the SCIM user
scenarios section is taken from them.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
7.2. Informative References
[I-D.ietf-scim-api]
Hunt, P., Grizzle, K., Ansari, M., Wahlstroem, E., and C.
Mortimore, "System for Cross-Domain Identity Management:
Protocol", draft-ietf-scim-api-17 (work in progress),
April 2015.
[I-D.ietf-scim-core-schema]
Hunt, P., Grizzle, K., Wahlstroem, E., and C. Mortimore,
"System for Cross-Domain Identity Management: Core
Schema", draft-ietf-scim-core-schema-18 (work in
progress), April 2015.
Authors' Addresses
Kepeng LI (editor)
Alibaba Group
Wenyixi Road, Yuhang District
Hangzhou, Zhejiang 311121
China
Email: kepeng.lkp@alibaba-inc.com
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Phil Hunt
Oracle
Email: phil.hunt@oracle.com
Bhumip Khasnabish
ZTE (TX) Inc.
55 Madison Ave, Suite 302
Morristown, New Jersey 07960
USA
Phone: +001-781-752-8003
Email: vumip1@gmail.com, bhumip.khasnabish@ztetx.com
URI: http://tinyurl.com/bhumip/
Anthony Nadalin
Microsoft
Email: tonynad@microsoft.com
Zachary Zeltsan
Individual
Email: Zachary.Zeltsan@gmail.com
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