draft-ietf-secevent-http-poll-04.txt   draft-ietf-secevent-http-poll-05.txt 
Network Working Group A. Backman, Ed. Network Working Group A. Backman, Ed.
Internet-Draft Amazon Internet-Draft Amazon
Intended status: Standards Track M. Jones, Ed. Intended status: Standards Track M. Jones, Ed.
Expires: May 4, 2020 Microsoft Expires: May 21, 2020 Microsoft
M. Scurtescu M. Scurtescu
Coinbase Coinbase
M. Ansari M. Ansari
Cisco Cisco
A. Nadalin A. Nadalin
Microsoft Microsoft
November 1, 2019 November 18, 2019
Poll-Based Security Event Token (SET) Delivery Using HTTP Poll-Based Security Event Token (SET) Delivery Using HTTP
draft-ietf-secevent-http-poll-04 draft-ietf-secevent-http-poll-05
Abstract Abstract
This specification defines how a series of Security Event Tokens This specification defines how a series of Security Event Tokens
(SETs) may be delivered to an intended recipient using HTTP POST over (SETs) may be delivered to an intended recipient using HTTP POST over
TLS initiated as a poll by the recipient. The specification also TLS initiated as a poll by the recipient. The specification also
defines how delivery can be assured, subject to the SET Recipient's defines how delivery can be assured, subject to the SET Recipient's
need for assurance. need for assurance.
Status of This Memo Status of This Memo
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on May 4, 2020. This Internet-Draft will expire on May 21, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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Table of Contents Table of Contents
1. Introduction and Overview . . . . . . . . . . . . . . . . . . 2 1. Introduction and Overview . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3 1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
2. SET Delivery . . . . . . . . . . . . . . . . . . . . . . . . 3 2. SET Delivery . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Polling Delivery using HTTP . . . . . . . . . . . . . . . 4 2.1. Polling Delivery using HTTP . . . . . . . . . . . . . . . 4
2.2. Polling HTTP Request . . . . . . . . . . . . . . . . . . 4 2.2. Polling HTTP Request . . . . . . . . . . . . . . . . . . 4
2.3. Polling HTTP Response . . . . . . . . . . . . . . . . . . 5 2.3. Polling HTTP Response . . . . . . . . . . . . . . . . . . 5
2.4. Poll Request . . . . . . . . . . . . . . . . . . . . . . 6 2.4. Poll Request . . . . . . . . . . . . . . . . . . . . . . 6
2.4.1. Poll Only Request . . . . . . . . . . . . . . . . . . 7 2.4.1. Poll Only Request . . . . . . . . . . . . . . . . . . 6
2.4.2. Acknowledge Only Request . . . . . . . . . . . . . . 7 2.4.2. Acknowledge Only Request . . . . . . . . . . . . . . 7
2.4.3. Poll with Acknowledgement . . . . . . . . . . . . . . 8 2.4.3. Poll with Acknowledgement . . . . . . . . . . . . . . 8
2.4.4. Poll with Acknowledgement and Errors . . . . . . . . 9 2.4.4. Poll with Acknowledgement and Errors . . . . . . . . 9
2.5. Poll Response . . . . . . . . . . . . . . . . . . . . . . 9 2.5. Poll Response . . . . . . . . . . . . . . . . . . . . . . 9
2.5.1. Poll Error Response . . . . . . . . . . . . . . . . . 11
2.6. Error Response Handling . . . . . . . . . . . . . . . . . 11 2.6. Error Response Handling . . . . . . . . . . . . . . . . . 11
3. Authentication and Authorization . . . . . . . . . . . . . . 12 3. Authentication and Authorization . . . . . . . . . . . . . . 12
3.1. Use of Tokens as Authorizations . . . . . . . . . . . . . 12
4. Security Considerations . . . . . . . . . . . . . . . . . . . 12 4. Security Considerations . . . . . . . . . . . . . . . . . . . 12
4.1. Authentication Using Signed SETs . . . . . . . . . . . . 13 4.1. Authentication Using Signed SETs . . . . . . . . . . . . 12
4.2. HTTP Considerations . . . . . . . . . . . . . . . . . . . 13 4.2. HTTP Considerations . . . . . . . . . . . . . . . . . . . 13
4.3. Confidentiality of SETs . . . . . . . . . . . . . . . . . 13 4.3. Confidentiality of SETs . . . . . . . . . . . . . . . . . 13
4.4. Access Token Considerations . . . . . . . . . . . . . . . 13 4.4. Access Token Considerations . . . . . . . . . . . . . . . 13
4.4.1. Bearer Token Considerations . . . . . . . . . . . . . 13 4.4.1. Bearer Token Considerations . . . . . . . . . . . . . 13
5. Privacy Considerations . . . . . . . . . . . . . . . . . . . 14 5. Privacy Considerations . . . . . . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative References . . . . . . . . . . . . . . . . . . 14 7.1. Normative References . . . . . . . . . . . . . . . . . . 14
7.2. Informative References . . . . . . . . . . . . . . . . . 16 7.2. Informative References . . . . . . . . . . . . . . . . . 16
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 17 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 17
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 17 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction and Overview 1. Introduction and Overview
This specification defines how a stream of Security Event Tokens This specification defines how a stream of Security Event Tokens
(SETs) [RFC8417] can be transmitted to an intended SET Recipient (SETs) [RFC8417] can be transmitted to an intended SET Recipient
using HTTP [RFC7231] over TLS. The specification defines a method to using HTTP [RFC7231] over TLS. The specification defines a method to
poll for SETs using HTTP POST. poll for SETs using HTTP POST. This is an alternative SET delivery
method to the one defined in [I-D.ietf-secevent-http-push].
A mechanism for exchanging configuration metadata such as endpoint A mechanism for exchanging configuration metadata such as endpoint
URLs and cryptographic key parameters between the transmitter and URLs and cryptographic key parameters between the transmitter and
recipient is out of scope for this specification. How SETs are recipient is out of scope for this specification. How SETs are
defined and the process by which events are identified for SET defined and the process by which security events are identified for
Recipients is also out of scope for this specification. SET Recipients are specified in [RFC8417].
1.1. Notational Conventions 1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
Throughout this document, all figures MAY contain spaces and extra Throughout this document, all figures MAY contain spaces and extra
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to an HTTP POST request to the SET Transmitter. Then in a following to an HTTP POST request to the SET Transmitter. Then in a following
request, the SET Recipient acknowledges received SETs and can poll request, the SET Recipient acknowledges received SETs and can poll
for more. All requests and responses are JSON documents and use a for more. All requests and responses are JSON documents and use a
"Content-Type" of "application/json", as described in Section 2.1. "Content-Type" of "application/json", as described in Section 2.1.
After successful (acknowledged) SET delivery, SET Transmitters are After successful (acknowledged) SET delivery, SET Transmitters are
not required to retain or record SETs for retransmission. Once a SET not required to retain or record SETs for retransmission. Once a SET
is acknowledged, the SET Recipient SHALL be responsible for is acknowledged, the SET Recipient SHALL be responsible for
retention, if needed. retention, if needed.
Transmitted SETs SHOULD be self-validating (signed) if there is a
requirement to verify they were issued by the SET Transmitter at a
later date when de-coupled from the original delivery where
authenticity could be checked via the HTTP or TLS mutual
authentication.
Upon receiving a SET, the SET Recipient reads the SET and validates Upon receiving a SET, the SET Recipient reads the SET and validates
it in the manner described in Section 2 of it in the manner described in Section 2 of
[I-D.ietf-secevent-http-push]. The SET Recipient MUST acknowledge [I-D.ietf-secevent-http-push]. The SET Recipient MUST acknowledge
receipt to the SET Transmitter. The SET Recipient SHALL NOT use the receipt to the SET Transmitter. The SET Recipient SHALL NOT use the
event acknowledgement mechanism to report event errors other than event acknowledgement mechanism to report event errors other than
those relating to the parsing and validation of the SET. those relating to the parsing and validation of the SET.
2.1. Polling Delivery using HTTP 2.1. Polling Delivery using HTTP
This method allows a SET Recipient to use HTTP POST (Section 4.3.3 of 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 [RFC7231]) to acknowledge SETs and to check for and receive zero or
more SETs. Requests MAY be made at a periodic interval (short more SETs. Requests MAY be made at a periodic interval (short
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Transmitter SHOULD return an immediate response even if no Transmitter SHOULD return an immediate response even if no
results are available (short polling). The default value is results are available (short polling). The default value is
"false", which indicates the request is to be treated as an "false", which indicates the request is to be treated as an
HTTP Long Poll, per Section 2 of [RFC6202]. The timeout for HTTP Long Poll, per Section 2 of [RFC6202]. The timeout for
the request is part of the configuration between the the request is part of the configuration between the
participants, which is out of scope of this specification. participants, which is out of scope of this specification.
SET Acknowledgment Parameters SET Acknowledgment Parameters
ack ack
An array of strings that each corresponds to the "jti" of a A JSON array of strings whose values are the "jti" values of
successfully received SET. If there are no outstanding SETs to successfully received SETs that are being acknowledged. If
acknowledge, the member MAY be omitted. When acknowledging a there are no outstanding SETs to acknowledge, this member is
SET, the SET Transmitter is released from any obligation to omitted. When acknowledging a SET, the SET Transmitter is
retain the SET. released from any obligation to retain the SET.
setErrs setErrs
A JSON Object that contains one or more nested JSON object A JSON object with one or more members whose keys are the "jti"
members that correspond to the "jti" of each invalid SET values of invalid SETs received. The values of these objects
received. The value of each is a JSON object whose contents is are themselves JSON objects that describe the errors detected
an "err" member and "description" member, whose values using the "err" and "description" values specified in
correspond to the errors described in Section 2.6. Section 2.6. If there are no outstanding SETs with errors to
return, this member is omitted.
2.3. Polling HTTP Response 2.3. Polling HTTP Response
In response to a poll request, the SET Transmitter checks for In response to a poll request, the SET Transmitter checks for
available SETs and responds with a JSON document containing the available SETs and responds with a JSON document containing the
following JSON object members: following JSON object members:
sets sets
A JSON object that contains zero or more nested JSON objects. A JSON object that contains zero or more nested JSON objects.
Each nested JSON object's key corresponds to the "jti" of a SET to Each nested JSON object's key corresponds to the "jti" of a SET to
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are available to be returned. are available to be returned.
When making a response, the HTTP header "Content-Type" is set to When making a response, the HTTP header "Content-Type" is set to
"application/json". "application/json".
2.4. Poll Request 2.4. Poll Request
The SET Recipient performs an HTTP POST (see Section 4.3.4 of 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 [RFC7231]) to a pre-arranged polling endpoint URI to check for SETs
that are available. Because the SET Recipient has no prior SETs to that are available. Because the SET Recipient has no prior SETs to
acknowledge, the "ack" and "errs" request parameters are omitted. acknowledge, the "ack" and "setErrs" request parameters are omitted.
If after a period of time, negotiated between the SET Transmitter and After a period of time configured between the SET Transmitter and
Recipient, a SET Transmitter MAY redeliver SETs it has previously Recipient, a SET Transmitter MAY redeliver SETs it has previously
delivered. The SET Recipient SHOULD accept repeat SETs and delivered. The SET Recipient SHOULD accept repeat SETs and
acknowledge the SETs regardless of whether the Recipient believes it acknowledge the SETs regardless of whether the Recipient believes it
has already acknowledged the SETs previously. A SET Transmitter MAY has already acknowledged the SETs previously. A SET Transmitter MAY
limit the number of times it attempts to deliver a SET. limit the number of times it attempts to deliver a SET.
If the SET Recipient has received SETs from the SET Transmitter, the If the SET Recipient has received SETs from the SET Transmitter, the
SET Recipient SHOULD parse and validate received SETs to meet its own SET Recipient SHOULD parse and validate received SETs to meet its own
requirements and SHOULD acknowledge receipt in a timely fashion requirements and SHOULD acknowledge receipt in a timely fashion
(e.g., seconds or minutes) so that the SET Transmitter can mark the (e.g., seconds or minutes) so that the SET Transmitter can mark the
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Poll requests have three variations: Poll requests have three variations:
Poll Only Poll Only
In which a SET Recipient asks for the next set of events where no In which a SET Recipient asks for the next set of events where no
previous SET deliveries are acknowledged (such as in the initial previous SET deliveries are acknowledged (such as in the initial
poll request). poll request).
Acknowledge Only Acknowledge Only
In which a SET Recipient sets the "maxEvents" value to "0" along In which a SET Recipient sets the "maxEvents" value to "0" along
with "ack" and "err" members indicating the SET Recipient is with "ack" and "setErrs" members indicating the SET Recipient is
acknowledging previously received SETs and does not want to acknowledging previously received SETs and does not want to
receive any new SETs in response to the request. receive any new SETs in response to the request.
Combined Acknowledge and Poll Combined Acknowledge and Poll
In which a SET Recipient is both acknowledging previously received In which a SET Recipient is both acknowledging previously received
SETs using the "ack" and "err" members and will wait for the next SETs using the "ack" and "setErrs" members and will wait for the
group of SETs in the SET Transmitters response. next group of SETs in the SET Transmitters response.
2.4.1. Poll Only Request 2.4.1. Poll Only Request
In the case where no SETs were received in a previous poll (see In the case where no SETs were received in a previous poll (see
Figure 7), the SET Recipient simply polls without acknowledgement Figure 7), the SET Recipient simply polls without acknowledgement
parameters ("sets" and "setErrs"). parameters ("ack" and "setErrs").
The following is an example request made by a SET Recipient that has The following is an example request made by a SET Recipient that has
no outstanding SETs to acknowledge and is polling for available SETs no outstanding SETs to acknowledge and is polling for available SETs
at the endpoint "https://nofity.exampleidp.com/Events": at the endpoint "https://nofity.exampleidp.com/Events":
POST /Events HTTP/1.1 POST /Events HTTP/1.1
Host: notify.exampleidp.com Host: notify.exampleidp.com
Content-Type: application/json Content-Type: application/json
{ {
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"description": "The audience value was invalid." "description": "The audience value was invalid."
} }
}, },
"returnImmediately": true "returnImmediately": true
} }
Figure 5: Example Poll Acknowledgement with Error Figure 5: Example Poll Acknowledgement with Error
2.5. Poll Response 2.5. Poll Response
In response to a poll request, the service provider MAY respond In response to a valid poll request, the service provider MAY respond
immediately if SETs are available to be delivered. If no SETs are immediately if SETs are available to be delivered. If no SETs are
available at the time of the request, the SET Transmitter SHALL delay available at the time of the request, the SET Transmitter SHALL delay
responding until a SET is available or the timeout interval has responding until a SET is available or the timeout interval has
elapsed unless the poll request parameter "returnImmediately" is elapsed unless the poll request parameter "returnImmediately" is
"true". "true".
As described in Section 2.3, a JSON document is returned containing a As described in Section 2.3, a JSON document is returned containing a
number of members including "sets", which SHALL contain zero or more number of members including "sets", which SHALL contain zero or more
SETs. SETs.
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Content-Type: application/json Content-Type: application/json
{ {
"sets": {} "sets": {}
} }
Figure 7: Example No SETs Poll Response Figure 7: Example No SETs Poll Response
Upon receiving the JSON document (e.g., as shown in Figure 6), the 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 Recipient parses and verifies the received SETs and notifies the
SET Transmitter via the next poll request to the SET Transmitter, as SET Transmitter of successfully received SETs and SETs with errors
described in Section 2.4.3 or Section 2.4.4. via the next poll request to the SET Transmitter, as described in
Section 2.4.3 or Section 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 SHOULD respond with
an appropriate 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.
The following is a non-normative example of a response to an invalid
poll request:
HTTP/1.1 400 Bad Request
Example Poll Error Response
2.6. Error Response Handling 2.6. Error Response Handling
If a SET is invalid, error codes from the IANA "Security Event Token If a SET is invalid, error codes from the IANA "Security Event Token
Delivery Error Codes" registry established by Delivery Error Codes" registry established by
[I-D.ietf-secevent-http-push] are used in error responses. As [I-D.ietf-secevent-http-push] are used in error responses. As
described in Section 2.3 of [I-D.ietf-secevent-http-push], an error described in Section 2.3 of [I-D.ietf-secevent-http-push], an error
response is a JSON object providing details about the error that response is a JSON object providing details about the error that
includes the following name/value pairs: includes the following name/value pairs:
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The SET delivery method described in this specification is based upon The SET delivery method described in this specification is based upon
HTTP and depends on the use of TLS and/or standard HTTP HTTP and depends on the use of TLS and/or standard HTTP
authentication and authorization schemes, as per [RFC7235]. authentication and authorization schemes, as per [RFC7235].
As per Section 4.1 of [RFC7235], a SET delivery endpoint SHALL As per Section 4.1 of [RFC7235], a SET delivery endpoint SHALL
indicate supported HTTP authentication schemes via the "WWW- indicate supported HTTP authentication schemes via the "WWW-
Authenticate" header. Authenticate" header.
Authorization for the ability to pick-up or deliver SETs can be Authorization for the ability to pick-up or deliver SETs can be
determined by using the identity of the SET issuer, or via an determined by using the identity of the SET issuer, or via other
authentication method above. This specification considers employed authentication methods. Among other benefits,
authentication as a feature to prevent denial-of-service attacks. authentication can help prevent denial-of-service attacks. Because
Because SETs are not commands, SET Recipients are free to ignore SETs SETs are not commands, SET Recipients are free to ignore SETs that
that are not of interest after acknowledging their receipt. are not of interest after acknowledging their receipt.
3.1. Use of Tokens as Authorizations
When using bearer tokens or proof-of-possession tokens that represent
an authorization grant such as issued by OAuth (see [RFC6749]),
implementers SHOULD consider the type of authorization granted, any
authorized scopes (see Section 3.3 of [RFC6749]), and the security
subject(s) that SHOULD be mapped from the authorization when
considering local access control rules. Section 6 of the OAuth
Assertion Framework specification [RFC7521] documents common
scenarios for authorization including:
o Clients using an assertion to authenticate and/or act on behalf of
itself;
o Clients acting on behalf of a user; and,
o A Client acting on behalf of an anonymous user.
When using OAuth access tokens, implementers MUST take into account
the threats and countermeasures documented in the security
considerations for the use of client authorizations (see Section 8 of
[RFC7521]). When using other token formats or frameworks,
implementers MUST take into account similar threats and
countermeasures, especially those documented by the relevant
specifications.
4. Security Considerations 4. Security Considerations
4.1. Authentication Using Signed SETs 4.1. Authentication Using Signed SETs
In scenarios where HTTP authorization or TLS mutual authentication In scenarios where HTTP authorization or TLS mutual authentication
are not used or are considered weak, JWS signed SETs SHOULD be used are not used or are considered weak, JWS signed SETs SHOULD be used
(see [RFC7515] and Section 5 of [RFC8417]). This enables the SET (see [RFC7515] and Section 5 of [RFC8417]). This enables the SET
Recipient to validate that the SET issuer is authorized to deliver Recipient to validate that the SET issuer is authorized to deliver
the SET. the SET.
4.2. HTTP Considerations 4.2. HTTP Considerations
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This specification requires no IANA actions. This specification requires no IANA actions.
7. References 7. References
7.1. Normative References 7.1. Normative References
[I-D.ietf-secevent-http-push] [I-D.ietf-secevent-http-push]
Backman, A., Jones, M., Scurtescu, M., Ansari, M., and A. Backman, A., Jones, M., Scurtescu, M., Ansari, M., and A.
Nadalin, "Push-Based Security Event Token (SET) Delivery Nadalin, "Push-Based Security Event Token (SET) Delivery
Using HTTP", draft-ietf-secevent-http-push-06 (work in Using HTTP", draft-ietf-secevent-http-push-07 (work in
progress), May 2019. progress), July 2019.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005, RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>. <https://www.rfc-editor.org/info/rfc3986>.
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o Removed unnecessary HTTP headers in examples and added Content- o Removed unnecessary HTTP headers in examples and added Content-
Type. Type.
o Added Content-Language requirement for error descriptions, o Added Content-Language requirement for error descriptions,
aligning with http-push. aligning with http-push.
o Stated that bearer tokens SHOULD have a limited lifetime. o Stated that bearer tokens SHOULD have a limited lifetime.
o Minor editorial fixes. o Minor editorial fixes.
Draft 05 - AB + mbj
o Added normative text defining how to respond to invalid poll
requests.
o Addressed shepherd comments by Yaron Sheffer.
Authors' Addresses Authors' Addresses
Annabelle Backman (editor) Annabelle Backman (editor)
Amazon Amazon
Email: richanna@amazon.com Email: richanna@amazon.com
Michael B. Jones (editor) Michael B. Jones (editor)
Microsoft Microsoft
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