Poll-Based Security Event Token (SET) Delivery Using HTTP
RFC 8936
| Document | Type | RFC - Proposed Standard (November 2020; No errata) | |
|---|---|---|---|
| Authors | Annabelle Backman , Michael Jones , Marius Scurtescu , Morteza Ansari , Anthony Nadalin | ||
| Last updated | 2020-11-30 | ||
| Replaces | draft-ietf-secevent-delivery | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | plain text html xml pdf htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Yaron Sheffer | ||
| Shepherd write-up | Show (last changed 2019-11-19) | ||
| IESG | IESG state | RFC 8936 (Proposed Standard) | |
| Action Holders |
(None)
|
||
| Consensus Boilerplate | Yes | ||
| Telechat date | |||
| Responsible AD | Benjamin Kaduk | ||
| Send notices to | Yaron Sheffer <yaronf.ietf@gmail.com> | ||
| IANA | IANA review state | IANA OK - No Actions Needed | |
| IANA action state | No IANA Actions | ||
Internet Engineering Task Force (IETF) A. Backman, Ed.
Request for Comments: 8936 Amazon
Category: Standards Track M. Jones, Ed.
ISSN: 2070-1721 Microsoft
M. Scurtescu
Coinbase
M. Ansari
A. Nadalin
Independent
November 2020
Poll-Based Security Event Token (SET) Delivery Using HTTP
Abstract
This specification defines how a series of Security Event Tokens
(SETs) can be delivered to an intended recipient using HTTP POST over
TLS initiated as a poll by the recipient. The specification also
defines how delivery can be assured, subject to the SET Recipient's
need for assurance.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8936.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction and Overview
1.1. Notational Conventions
1.2. Definitions
2. SET Delivery
2.1. Polling Delivery using HTTP
2.2. Polling HTTP Request
2.3. Polling HTTP Response
2.4. Poll Request
2.4.1. Poll-Only Request
2.4.2. Acknowledge-Only Request
2.4.3. Poll with Acknowledgement
2.4.4. Poll with Acknowledgement and Errors
2.5. Poll Response
2.5.1. Poll Error Response
2.6. Error Response Handling
3. Authentication and Authorization
4. Security Considerations
4.1. Authentication Using Signed SETs
4.2. HTTP Considerations
4.3. Confidentiality of SETs
4.4. Access Token Considerations
4.4.1. Bearer Token Considerations
5. Privacy Considerations
6. IANA Considerations
7. References
7.1. Normative References
7.2. Informative References
Appendix A. Unencrypted Transport Considerations
Acknowledgments
Authors' Addresses
1. Introduction and Overview
This specification defines how a stream of Security Event Tokens
(SETs) [RFC8417] can be transmitted to an intended SET Recipient
using HTTP [RFC7231] over TLS. The specification defines a method to
poll for SETs using HTTP POST. This is an alternative SET delivery
method to the one defined in [RFC8935].
Poll-based SET delivery is intended for scenarios where all of the
following apply:
* The recipient of the SET is capable of making outbound HTTP
requests.
* The transmitter is capable of hosting a TLS-enabled HTTP endpoint
that is accessible to the recipient.
* The transmitter and recipient are willing to exchange data with
one another.
In some scenarios, either push-based or poll-based delivery could be
used, and in others, only one of them would be applicable.
A mechanism for exchanging configuration metadata such as endpoint
URLs, cryptographic keys, and possible implementation constraints
such as buffer size limitations between the transmitter and recipient
is out of scope for this specification. How SETs are defined and the
process by which security events are identified for SET Recipients
are specified in [RFC8417].
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Throughout this document, all figures may contain spaces and extra
line wrapping for readability and due to space limitations.
1.2. Definitions
This specification utilizes terminology defined in [RFC8417] and
[RFC8935].
2. SET Delivery
When a SET is available for a SET Recipient, the SET Transmitter
queues the SET in a buffer so that a SET Recipient can poll for SETs
using HTTP POST.
In poll-based SET delivery using HTTP over TLS, zero or more SETs are
delivered in a JSON [RFC8259] document to a SET Recipient in response
to an HTTP POST request to the SET Transmitter. Then in a following
request, the SET Recipient acknowledges received SETs and can poll
for more. All requests and responses are JSON documents and use a
"Content-Type" of "application/json", as described in Section 2.2.
After successful (acknowledged) SET delivery, SET Transmitters are
not required to retain or record SETs for retransmission. Once a SET
is acknowledged, the SET Recipient SHALL be responsible for
retention, if needed. Transmitters may also discard undelivered SETs
under deployment-specific conditions, such as if they have not been
polled for over too long a period of time or if an excessive amount
of storage is needed to retain them.
Upon receiving a SET, the SET Recipient reads the SET and validates
it in the manner described in Section 2 of [RFC8935]. The SET
Recipient MUST acknowledge receipt to the SET Transmitter, and SHOULD
do so in a timely fashion, as described in Section 2.4. The SET
Recipient SHALL NOT use the event acknowledgement mechanism to report
event errors other than those relating to the parsing and validation
of the SET.
2.1. Polling Delivery using HTTP
This method allows a SET Recipient to use HTTP POST (Section 4.3.3 of
[RFC7231]) to acknowledge SETs and to check for and receive zero or
more SETs. Requests MAY be made at a periodic interval (short
polling) or requests MAY wait, pending availability of new SETs using
long polling, per Section 2 of [RFC6202]. Note that short polling
will result in retrieving zero or more SETs whereas long polling will
typically result in retrieving one or more SETs unless a timeout
occurs.
The delivery of SETs in this method is facilitated by HTTP POST
requests initiated by the SET Recipient in which:
* The SET Recipient makes a request for available SETs using an HTTP
POST to a pre-arranged endpoint provided by the SET Transmitter,
or
* after validating previously received SETs, the SET Recipient
initiates another poll request using HTTP POST that includes
acknowledgement of previous SETs and requests the next batch of
SETs.
The purpose of the acknowledgement is to inform the SET Transmitter
that delivery has succeeded and redelivery is no longer required.
Before acknowledgement, SET Recipients validate the received SETs and
retain them in a manner appropriate to the recipient's requirements.
The level and method of retention of SETs by SET Recipients is out of
scope of this specification.
2.2. Polling HTTP Request
When initiating a poll request, the SET Recipient constructs a JSON
document that consists of polling request parameters and SET
acknowledgement parameters in the form of JSON objects.
When making a request, the HTTP "Content-Type" header field is set to
"application/json".
The following JSON object members are used in a polling request:
Request Processing Parameters
maxEvents
An OPTIONAL integer value indicating the maximum number of
unacknowledged SETs to be returned. The SET Transmitter SHOULD
NOT send more SETs than the specified maximum. If more than
the maximum number of SETs are available, the SET Transmitter
determines which to return first; the oldest SETs available MAY
be returned first, or another selection algorithm MAY be used,
such as prioritizing SETs in some manner that makes sense for
the use case. A value of "0" MAY be used by SET Recipients
that would like to perform an acknowledge-only request. This
enables the Recipient to use separate HTTP requests for
acknowledgement and reception of SETs. If this parameter is
omitted, no limit is placed on the number of SETs to be
returned.
returnImmediately
An OPTIONAL JSON boolean value that indicates the SET
Transmitter SHOULD return an immediate response even if no
results are available (short polling). The default value is
"false", which indicates the request is to be treated as an
HTTP long poll, per Section 2 of [RFC6202]. The timeout for
the request is part of the configuration between the
participants, which is out of scope of this specification.
SET Acknowledgment Parameters
ack
A JSON array of strings whose values are the "jti" [RFC7519]
values of successfully received SETs that are being
acknowledged. If there are no outstanding SETs to acknowledge,
this member is omitted or contains an empty array. Once a SET
has been acknowledged, the SET Transmitter is released from any
obligation to retain the SET.
setErrs
A JSON object with one or more members whose keys are the "jti"
values of invalid SETs received. The values of these objects
are themselves JSON objects that describe the errors detected
using the "err" and "description" values specified in
Section 2.6. If there are no outstanding SETs with errors to
report, this member is omitted or contains an empty JSON
object.
2.3. Polling HTTP Response
In response to a poll request, the SET Transmitter checks for
available SETs and responds with a JSON document containing the
following JSON object members:
sets
A JSON object containing zero or more SETs being returned. Each
member name is the "jti" of a SET to be delivered, and its value
is a JSON string representing the corresponding SET. If there are
no outstanding SETs to be transmitted, the JSON object SHALL be
empty. Note that both SETs being transmitted for the first time
and SETs that are being retransmitted after not having been
acknowledged are communicated here.
moreAvailable
A JSON boolean value that indicates if more unacknowledged SETs
are available to be returned. This member MAY be omitted, with
the meaning being the same as including it with the boolean value
"false".
When making a response, the HTTP "Content-Type" header field is set
to "application/json".
2.4. Poll Request
The SET Recipient performs an HTTP POST (see Section 4.3.4 of
[RFC7231]) to a pre-arranged polling endpoint URI to check for SETs
that are available. Because the SET Recipient has no prior SETs to
acknowledge, the "ack" and "setErrs" request parameters are omitted.
After a period of time configured in an out-of-band manner between
the SET Transmitter and Recipient, a SET Transmitter MAY redeliver
SETs it has previously delivered. The SET Recipient SHOULD accept
repeat SETs and acknowledge the SETs regardless of whether the
Recipient believes it has already acknowledged the SETs previously.
A SET Transmitter MAY limit the number of times it attempts to
deliver a SET.
If the SET Recipient has received SETs from the SET Transmitter, the
SET Recipient parses and validates that received SETs meet its own
requirements and SHOULD acknowledge receipt in a timely fashion
(e.g., seconds or minutes) so that the SET Transmitter can mark the
SETs as received. SET Recipients SHOULD acknowledge receipt before
taking any local actions based on the SETs to avoid unnecessary delay
in acknowledgement, where possible.
Poll requests have three variations:
Poll-Only
In this scenario, a SET Recipient asks for the next set of
events where no previous SET deliveries are acknowledged (such
as in the initial poll request).
Acknowledge-Only
In this scenario, a SET Recipient sets the "maxEvents" value to
"0" along with "ack" and "setErrs" members indicating the SET
Recipient is acknowledging previously received SETs and does
not want to receive any new SETs in response to the request.
Combined Acknowledge and Poll
In this scenario, a SET Recipient is both acknowledging
previously received SETs using the "ack" and "setErrs" members
and will wait for the next group of SETs in the SET
Transmitters response.
2.4.1. Poll-Only Request
In the case where no SETs were received in a previous poll (see
Figure 7), the SET Recipient simply polls without acknowledgement
parameters ("ack" and "setErrs").
The following is a non-normative example request made by a SET
Recipient that has no outstanding SETs to acknowledge and is polling
for available SETs at the endpoint "https://notify.idp.example.com/
Events":
POST /Events HTTP/1.1
Host: notify.idp.example.com
Content-Type: application/json
{
"returnImmediately": true
}
Figure 1: Example Initial Poll Request
A SET Recipient can poll using default parameter values by passing an
empty JSON object.
The following is a non-normative example default poll request to the
endpoint "https://notify.idp.example.com/Events":
POST /Events HTTP/1.1
Host: notify.idp.example.com
Content-Type: application/json
{}
Figure 2: Example Default Poll Request
2.4.2. Acknowledge-Only Request
In this variation, the SET Recipient acknowledges previously received
SETs and indicates it does not want to receive SETs in response by
setting the "maxEvents" value to "0". This variation might be used,
for instance, when a SET Recipient needs to acknowledge received SETs
independently (e.g., on separate threads) from the process of
receiving SETs.
If the poll needs to return immediately, then "returnImmediately"
MUST also be present with the value "true". If it is "false", then a
long poll will still occur until an event is ready to be returned,
even though no events will be returned.
The following is a non-normative example poll request with
acknowledgement of SETs received (for example, as shown in Figure 6):
POST /Events HTTP/1.1
Host: notify.idp.example.com
Content-Type: application/json
{
"ack": [
"4d3559ec67504aaba65d40b0363faad8",
"3d0c3cf797584bd193bd0fb1bd4e7d30"
],
"maxEvents": 0,
"returnImmediately": true
}
Figure 3: Example Acknowledge-Only Request
2.4.3. Poll with Acknowledgement
This variation allows a recipient thread to simultaneously
acknowledge previously received SETs and wait for the next group of
SETs in a single request.
The following is a non-normative example poll with acknowledgement of
the SETs received in Figure 6:
POST /Events HTTP/1.1
Host: notify.idp.example.com
Content-Type: application/json
{
"ack": [
"4d3559ec67504aaba65d40b0363faad8",
"3d0c3cf797584bd193bd0fb1bd4e7d30"
],
"returnImmediately": false
}
Figure 4: Example Poll with Acknowledgement and No Errors
In the above acknowledgement, the SET Recipient has acknowledged
receipt of two SETs and has indicated it wants to wait until the next
SET is available.
2.4.4. Poll with Acknowledgement and Errors
In the case where errors were detected in previously delivered SETs,
the SET Recipient MAY use the "setErrs" member to communicate the
errors in the following poll request.
The following is a non-normative example of a response acknowledging
one successfully received SET and one SET with an error from the two
SETs received in Figure 6:
POST /Events HTTP/1.1
Host: notify.idp.example.com
Content-Language: en-US
Content-Type: application/json
{
"ack": ["3d0c3cf797584bd193bd0fb1bd4e7d30"],
"setErrs": {
"4d3559ec67504aaba65d40b0363faad8": {
"err": "authentication_failed",
"description": "The SET could not be authenticated"
}
},
"returnImmediately": true
}
Figure 5: Example Poll Acknowledgement with Error
2.5. Poll Response
In response to a valid poll request, the service provider MAY respond
immediately if SETs are available to be delivered. If no SETs are
available at the time of the request, the SET Transmitter SHALL delay
responding until a SET is available or the timeout interval has
elapsed unless the poll request parameter "returnImmediately" is
present with the value "true".
As described in Section 2.3, a JSON document is returned containing
members including "sets", which SHALL contain zero or more SETs.
The following is a non-normative example response to the request
shown in Section 2.4. This example shows two SETs being returned:
HTTP/1.1 200 OK
Content-Type: application/json
{
"sets":
{
"4d3559ec67504aaba65d40b0363faad8":
"eyJhbGciOiJub25lIn0.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.",
"3d0c3cf797584bd193bd0fb1bd4e7d30":
"eyJhbGciOiJub25lIn0.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."
}
}
Figure 6: Example Poll Response
In the above example, two SETs whose "jti" values are
"4d3559ec67504aaba65d40b0363faad8" and
"3d0c3cf797584bd193bd0fb1bd4e7d30" are delivered.
The following is a non-normative example response to the request
shown in Section 2.4.1, which indicates that no new SETs or
unacknowledged SETs are available:
HTTP/1.1 200 OK
Content-Type: application/json
{
"sets": {}
}
Figure 7: Example No SETs Poll Response
Upon receiving the JSON document (e.g., as shown in Figure 6), the
SET Recipient parses and verifies the received SETs and notifies the
SET Transmitter of successfully received SETs and SETs with errors
via the next poll request to the SET Transmitter, as described in
Sections 2.4.3 and 2.4.4.
2.5.1. Poll Error Response
In the event of a general HTTP error condition in the context of
processing a poll request, the service provider responds with the
applicable HTTP response status code, as defined in Section 6 of
[RFC7231].
Service providers MAY respond to any invalid poll request with an
HTTP response status code of 400 (Bad Request) even when a more
specific code might apply, for example, if the service provider
deemed that a more specific code presented an information disclosure
risk. When no more specific code might apply, the service provider
SHALL respond to an invalid poll request with an HTTP status code of
400.
The response body for responses to invalid poll requests is left
undefined, and its contents SHOULD be ignored.
The following is a non-normative example of a response to an invalid
poll request:
HTTP/1.1 400 Bad Request
Figure 8: Example Poll Error Response
2.6. Error Response Handling
If a SET is invalid, error codes from the IANA "Security Event Token
Error Codes" registry established by [RFC8935] are used in error
responses. As described in Section 2.3 of [RFC8935], an error
response is a JSON object providing details about the error that
includes the following name/value pairs:
err: A value from the IANA "Security Event Token Error Codes"
registry that identifies the error.
description: A human-readable string that provides additional
diagnostic information.
When included as part of a batch of SETs, the above JSON is included
as part of the "setErrs" member, as defined in Sections 2.2 and
2.4.4.
When the SET Recipient includes one or more error responses in a
request to the SET Transmitter, it must also include in the request a
"Content-Language" header field whose value indicates the language of
the error descriptions included in the request. The method of
language selection in the case when the SET Recipient can provide
error messages in multiple languages is out of scope for this
specification.
3. Authentication and Authorization
The SET delivery method described in this specification is based upon
HTTP over TLS [RFC2818] and standard HTTP authentication and
authorization schemes, as per [RFC7235]. The TLS server certificate
MUST be validated using DNS-ID [RFC6125] and/or DNS-Based
Authentication of Named Entities (DANE) [RFC6698]. As per
Section 4.1 of [RFC7235], a SET delivery endpoint SHALL indicate
supported HTTP authentication schemes via the "WWW-Authenticate"
header field when using HTTP authentication.
Authorization for the eligibility to provide actionable SETs can be
determined by using the identity of the SET Issuer, validating the
identity of the SET Transmitter, or via other employed authentication
methods. Likewise, the SET Transmitter may choose to validate the
identity of the SET Recipient, perhaps using mutual TLS. Because
SETs are not commands, SET Recipients are free to ignore SETs that
are not of interest after acknowledging their receipt.
4. Security Considerations
4.1. Authentication Using Signed SETs
JWS signed SETs can be used (see [RFC7515] and Section 5 of
[RFC8417]) to enable the SET Recipient to validate that the SET
Issuer is authorized to provide actionable SETs.
4.2. HTTP Considerations
SET delivery depends on the use of the Hypertext Transfer Protocol
and is thus subject to the security considerations of HTTP (Section 9
of [RFC7230]) and its related specifications.
4.3. Confidentiality of SETs
SETs may contain sensitive information, including Personally
Identifiable Information (PII), or be distributed through third
parties. In such cases, SET Transmitters and SET Recipients MUST
protect the confidentiality of the SET contents. In some use cases,
using TLS to secure the transmitted SETs will be sufficient. In
other use cases, encrypting the SET as described in JSON Web
Encryption (JWE) [RFC7516] will also be required. The Event delivery
endpoint MUST support at least TLS version 1.2 [RFC5246] and SHOULD
support the newest version of TLS that meets its security
requirements, which as of the time of this publication is TLS 1.3
[RFC8446]. The client MUST perform a TLS/SSL server certificate
check using DNS-ID [RFC6125] and/or DANE [RFC6698]. How a SET
Recipient determines the expected service identity to match the SET
Transmitter's server certificate against is out of scope for this
document. The implementation security considerations for TLS in
"Recommendations for Secure Use of Transport Layer Security (TLS) and
Datagram Transport Layer Security (DTLS)" [RFC7525] MUST be followed.
4.4. Access Token Considerations
If HTTP Authentication is performed using OAuth access tokens
[RFC6749], implementers MUST take into account the threats and
countermeasures documented in Section 8 of [RFC7521].
4.4.1. Bearer Token Considerations
Transmitting bearer tokens [RFC6750] using TLS helps prevent their
interception.
Bearer tokens SHOULD have a limited lifetime that can be determined
directly or indirectly (e.g., by checking with a validation service)
by the service provider. By expiring tokens, clients are forced to
obtain a new token (which usually involves re-authentication) for
continued authorized access. For example, in OAuth 2.0, a client MAY
use an OAuth refresh token to obtain a new bearer token after
authenticating to an authorization server, per Section 6 of
[RFC6749].
Implementations supporting OAuth bearer tokens need to factor in
security considerations of this authorization method [RFC7521].
Since security is only as good as the weakest link, implementers also
need to consider authentication choices coupled with OAuth bearer
tokens. The security considerations of the default authentication
method for OAuth bearer tokens, HTTP Basic, are well documented in
[RFC7617]; therefore, implementers are encouraged to prefer stronger
authentication methods.
5. Privacy Considerations
SET Transmitters should attempt to deliver SETs that are targeted to
the specific business and protocol needs of subscribers.
When sharing personally identifiable information or information that
is otherwise considered confidential to affected users, SET
Transmitters and Recipients MUST have the appropriate legal
agreements and user consent or terms of service in place.
Furthermore, data that needs confidentiality protection MUST be
encrypted, at least with TLS and sometimes also using JSON Web
Encryption (JWE) [RFC7516].
In some cases, subject identifiers themselves may be considered
sensitive information, such that their inclusion within a SET may be
considered a violation of privacy. SET Issuers and SET Transmitters
should consider the ramifications of sharing a particular subject
identifier with a SET Recipient (e.g., whether doing so could enable
correlation and/or de-anonymization of data) and choose appropriate
subject identifiers for their use cases.
6. IANA Considerations
This document has no IANA actions.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
<https://www.rfc-editor.org/info/rfc2818>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <https://www.rfc-editor.org/info/rfc6125>.
[RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, DOI 10.17487/RFC6698, August
2012, <https://www.rfc-editor.org/info/rfc6698>.
[RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
DOI 10.17487/RFC7231, June 2014,
<https://www.rfc-editor.org/info/rfc7231>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <https://www.rfc-editor.org/info/rfc7515>.
[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)",
RFC 7516, DOI 10.17487/RFC7516, May 2015,
<https://www.rfc-editor.org/info/rfc7516>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>.
[RFC7521] Campbell, B., Mortimore, C., Jones, M., and Y. Goland,
"Assertion Framework for OAuth 2.0 Client Authentication
and Authorization Grants", RFC 7521, DOI 10.17487/RFC7521,
May 2015, <https://www.rfc-editor.org/info/rfc7521>.
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <https://www.rfc-editor.org/info/rfc7525>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
[RFC8417] Hunt, P., Ed., Jones, M., Denniss, W., and M. Ansari,
"Security Event Token (SET)", RFC 8417,
DOI 10.17487/RFC8417, July 2018,
<https://www.rfc-editor.org/info/rfc8417>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8935] Backman, A., Ed., Jones, M., Ed., Scurtescu, M., Ansari,
M., and A. Nadalin, "Push-Based Security Event Token (SET)
Delivery Using HTTP", RFC 8935, DOI 10.17487/RFC8935,
November 2020, <https://www.rfc-editor.org/info/rfc8935>.
7.2. Informative References
[RFC6202] Loreto, S., Saint-Andre, P., Salsano, S., and G. Wilkins,
"Known Issues and Best Practices for the Use of Long
Polling and Streaming in Bidirectional HTTP", RFC 6202,
DOI 10.17487/RFC6202, April 2011,
<https://www.rfc-editor.org/info/rfc6202>.
[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.
[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
Framework: Bearer Token Usage", RFC 6750,
DOI 10.17487/RFC6750, October 2012,
<https://www.rfc-editor.org/info/rfc6750>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[RFC7235] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Authentication", RFC 7235,
DOI 10.17487/RFC7235, June 2014,
<https://www.rfc-editor.org/info/rfc7235>.
[RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
RFC 7617, DOI 10.17487/RFC7617, September 2015,
<https://www.rfc-editor.org/info/rfc7617>.
Appendix A. Unencrypted Transport Considerations
Earlier versions of this specification made the use of TLS optional
and described security and privacy considerations resulting from use
of unencrypted HTTP as the underlying transport. When the working
group decided to mandate usage of HTTP over TLS, it also decided to
preserve the description of these considerations in a non-normative
manner.
The considerations for using unencrypted HTTP with this protocol are
the same as those described in Appendix A of [RFC8935], and are
therefore not repeated here.
Acknowledgments
The editors would like to thank the members of the SCIM Working
Group, which began discussions of provisioning events starting with
draft-hunt-scim-notify-00 in 2015. We would like to thank Phil Hunt
and the other authors of draft-ietf-secevent-delivery-02, upon which
this specification is based. We would like to thank the participants
in the SecEvents Working Group for their contributions to this
specification.
Additionally, we would like to thank the following individuals for
their reviews of this specification: Roman Danyliw, Martin Duke,
Benjamin Kaduk, Erik Kline, Murray Kucherawy, Warren Kumari, Barry
Leiba, Mark Nottingham, Alvaro Retana, Yaron Sheffer, Valery Smyslov,
Robert Sparks, Éric Vyncke, and Robert Wilton.
Authors' Addresses
Annabelle Backman (editor)
Amazon
Email: richanna@amazon.com
Michael B. Jones (editor)
Microsoft
Email: mbj@microsoft.com
URI: https://self-issued.info/
Marius Scurtescu
Coinbase
Email: marius.scurtescu@coinbase.com
Morteza Ansari
Independent
Email: morteza@sharppics.com
Anthony Nadalin
Independent
Email: nadalin@prodigy.net