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The Proxy-Status HTTP Response Header Field
draft-ietf-httpbis-proxy-status-08

Revision differences

Document history

Date Rev. By Action
2024-01-26
08 Gunter Van de Velde Request closed, assignment withdrawn: Ron Bonica Telechat OPSDIR review
2024-01-26
08 Gunter Van de Velde Closed request for Telechat review by OPSDIR with state 'Overtaken by Events': Cleaning up stale OPSDIR queue
2022-05-18
08 (System) RFC Editor state changed to AUTH48-DONE from AUTH48
2022-02-24
08 (System) RFC Editor state changed to AUTH48 from RFC-EDITOR
2022-02-04
08 (System) RFC Editor state changed to RFC-EDITOR from REF
2021-11-21
08 (System) RFC Editor state changed to REF from EDIT
2021-10-26
08 (System) IANA Action state changed to RFC-Ed-Ack from Waiting on RFC Editor
2021-10-25
08 (System) IANA Action state changed to Waiting on RFC Editor from In Progress
2021-10-25
08 (System) IANA Action state changed to In Progress from Waiting on Authors
2021-10-25
08 (System) IANA Action state changed to Waiting on Authors from In Progress
2021-10-25
08 (System) IANA Action state changed to In Progress from Waiting on Authors
2021-10-22
08 Amanda Baber IANA Experts State changed to Expert Reviews OK
2021-10-22
08 (System) IANA Action state changed to Waiting on Authors from In Progress
2021-10-22
08 (System) IANA Action state changed to In Progress from Waiting on Authors
2021-10-21
08 (System) IANA Action state changed to Waiting on Authors from In Progress
2021-10-20
08 (System) RFC Editor state changed to EDIT
2021-10-20
08 (System) IESG state changed to RFC Ed Queue from Approved-announcement sent
2021-10-20
08 (System) Announcement was received by RFC Editor
2021-10-20
08 (System) IANA Action state changed to In Progress
2021-10-20
08 Cindy Morgan IESG state changed to Approved-announcement sent from Approved-announcement to be sent
2021-10-20
08 Cindy Morgan IESG has approved the document
2021-10-20
08 Cindy Morgan Closed "Approve" ballot
2021-10-20
08 Cindy Morgan Ballot approval text was generated
2021-10-20
08 (System) Removed all action holders (IESG state changed)
2021-10-20
08 Francesca Palombini IESG state changed to Approved-announcement to be sent from IESG Evaluation
2021-10-14
08 Francesca Palombini IESG state changed to IESG Evaluation from IESG Evaluation::AD Followup
2021-10-13
08 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-08.txt
2021-10-13
08 (System) New version approved
2021-10-13
08 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-10-13
08 Mark Nottingham Uploaded new revision
2021-10-12
07 Benjamin Kaduk
[Ballot comment]
Thank you for the updates in the -07; they look good.

Two remarks on the new content in the -07:

In Section 2.1.1 …
[Ballot comment]
Thank you for the updates in the -07; they look good.

Two remarks on the new content in the -07:

In Section 2.1.1 the prose accompanying the example that uses
a 429 response code mentions "the reverse proxy", but the
Proxy-Status list members in the example have been changed to
no longer mention "SomeReverseProxy" in favor of an example hostname
specific to a given deployment.

The template for the proxy error types registry (Section 2.4), as
well as the initial registry contents in Sections 2.3.x, use the
phrase "Only generated by intermediaries".  My apologies if I made
this comment already and it was discarded, but that phrasing is
easy to misread as saying that the *error* was only generated by
intermediaries, when the intent is that the (possibly partial)
response content was only generated by intermediaries.  So I'd consider
adding "response", for "Response only generated by intermediaries"
(or similar) to forestall such confusion.
2021-10-12
07 Benjamin Kaduk [Ballot Position Update] Position for Benjamin Kaduk has been changed to No Objection from Discuss
2021-10-10
07 (System) Changed action holders to Francesca Palombini (IESG state changed)
2021-10-10
07 (System) Sub state has been changed to AD Followup from Revised ID Needed
2021-10-10
07 (System) IANA Review state changed to Version Changed - Review Needed from IANA OK - Actions Needed
2021-10-10
07 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-07.txt
2021-10-10
07 (System) New version approved
2021-10-10
07 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-10-10
07 Mark Nottingham Uploaded new revision
2021-08-27
06 Tommy Pauly
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated …
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header?

Proposed Standard, as indicated in the document. This is defining a new HTTP header to be used in interoperable production deployments. The type is indicated in the header.

(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections:

Technical Summary:

This document defines a new HTTP header that can be added to responses by intermediary proxies to report statuses and errors.

Working Group Summary:

The WG process for this document was smooth, over the past 2 years, getting decent amounts of feedback and input from the community. No major issues were raised.

Document Quality:

The document is of good quality, and seems ready for publication. Several implementations already exist and are deployed.

Personnel:

Document Shepherd: Tommy Pauly
Responsible AD: Francesca Palombini

(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG.

I reviewed this document, and am happy with the current state.

(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed?

This document, being relatively narrow, received a moderate amount of reviews, but in line with what we expect for the group.

(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place.

None specifically.

(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here.

No concerns.

(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

No IPR disclosures have been filed. All authors confirmed.

(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures.

No IPR disclosures have been filed.

(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it?

WG consensus seems clear; the document received less feedback than some of our larger documents, but was supported by the individuals engaged with this document (who also have the expertise in the topic).

(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise the areas of conflict in separate email messages to the Responsible Area Director. (It should be in a separate email because this questionnaire is publicly available.)

No discontent has been raised.

(11) Identify any ID nits the Document Shepherd has found in this document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough.

No nits found.

(12) Describe how the document meets any required formal review criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.

Not applicable.

(13) Have all references within this document been identified as either normative or informative?

Yes.

(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion?

No.

(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure.

No.

(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary.

No changes to existing RFCs.

(17) Describe the Document Shepherd's review of the IANA considerations section, especially with regard to its consistency with the body of the document. Confirm that all protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126).

The document is largely about defining a new header, which comes along with a new IANA registry to contain proxy-status fields. This is well written and clear.

(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries.

HTTP Proxy-Status Parameters registry

The HTTPbis WG should likely be consulted for selection of experts; having these experts be consistent with existing registries, such as the HTTP Cache Directive registry, would make sense.

(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.

ABNF rules are valid.

(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools (https://trac.ietf.org/trac/ops/wiki/yang-review-tools) for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?

Not applicable

2021-08-26
06 (System) Changed action holders to Mark Nottingham, Francesca Palombini, Piotr Sikora (IESG state changed)
2021-08-26
06 Cindy Morgan IESG state changed to IESG Evaluation::Revised I-D Needed from IESG Evaluation
2021-08-26
06 Martin Vigoureux [Ballot Position Update] New position, No Objection, has been recorded for Martin Vigoureux
2021-08-25
06 Murray Kucherawy
[Ballot comment]
Nice work, as usual for this WG.

Question 7 (an important one) in the shepherd writeup has not been properly answered.

I had …
[Ballot comment]
Nice work, as usual for this WG.

Question 7 (an important one) in the shepherd writeup has not been properly answered.

I had the same thought as Warren about seeing an example of multiple proxies being indicated, which in turn might report details.  I think I saw that there's a proposal for one to be included, so I'll go check that out.

Section 2:

* "... or when the request contains a header that activates a debugging mode." -- should that be "header field"?
2021-08-25
06 Murray Kucherawy [Ballot Position Update] New position, No Objection, has been recorded for Murray Kucherawy
2021-08-25
06 Benjamin Kaduk
[Ballot discuss]
draft-ietf-httpbis-semantics seems to require that in order to merge a
trailer field into the header section, the field definition both
explicitly permits the …
[Ballot discuss]
draft-ietf-httpbis-semantics seems to require that in order to merge a
trailer field into the header section, the field definition both
explicitly permits the merging action "and defines how trailer field
values can be safely merged."  The discussion in §2 of this document
about preserving ordering of trailer values relative to other
intermediaries seems to imply that trailer fields will be merged into
the header section (otherwise how could there be an order?), but I do not see a
specification for how to safely perform the merge operation.  Can we have
more clarity on the expected behavior in this case?
2021-08-25
06 Benjamin Kaduk
[Ballot comment]
Thanks to Rich Salz for the secdir review, and the authors for making
the indicated changes.

I made a couple pull requests with …
[Ballot comment]
Thanks to Rich Salz for the secdir review, and the authors for making
the indicated changes.

I made a couple pull requests with some suggested edits at:
https://github.com/httpwg/http-extensions/pull/1618
https://github.com/httpwg/http-extensions/pull/1619

Section 2.1.3

  The "next-protocol" parameter's value indicates the ALPN protocol
  identifier [RFC7301] used by the intermediary to connect to the next
  hop.  This is only applicable when that connection was actually
  established.

  The value MUST be either an sf-token or sf-binary, representing a TLS
  Application-Layer Protocol Negotiation (ALPN) Protocol ID (see

I do know about "h2c" and Upgrade, but I think there are cases where
neither TLS nor Upgrade is used.  Is there some way to indicate, e.g.,
that HTTP/1.1 without TLS was used?  I do not believe that setting
"http/1.1" here has those semantics in the way that "h2c" does, and it
seems that there may some value in indicating whether a secure transport
was used for the next hop in a similar way to how setting "h2" or "h3"
here would do so.

  [...] If the protocol
  identifier is able to be expressed as an sf-token using ASCII
  encoding, that form MUST be used.

There seems to be some ossification risk of the sf-binary form is never
used.  I would hope that the use of structured fields mitigates that
risk, since sf-binary support is needed in the generic field decoder,
but I don't know that I would specifically rely on it.  The MUST here
prohibits greasing to be sure; maybe the benefit of consistency
outweighs the risk, though.

Section 2.3.13

TLS protocol errors are typically accompanied by a TLS alert message
being generated; would the 'alert-id' and 'alert-message' extra
parameters be applicable here (in addition to for "tls_alert_received"
down in §2.3.15)?

Section 2.3.15

      -  alert-message: an sf-token containing the applicable
        description string from the TLS Alerts registry.  See
        [RFC8446].

I don't think there's a formal restriction on what characters are
allowed in description strings in the TLS Alerts registry, so that,
e.g., one could in theory have an alert description containing
characters like ";" that are not allowed in an sf-token.  It's so
unlikely to happen in practice that I'm not actually concerned, but I
will ask if we want to formally provide some behavior to allow for such
cases.

Section 2.3.24

      -  coding: an sf-token containing the specific coding that caused
        the error.

Is it worth referencing the registry of such codings?

Section 4

[I included some suggestions for additional detail in the security
considerations in my PR, mentioned above]

It is probably worth saying something about how there is no E2E
validation of accuracy, e.g., a proxy could claim that it used a secure
h2 or h3 transport for the next hop even though it didn't actually do
so.
2021-08-25
06 Benjamin Kaduk [Ballot Position Update] New position, Discuss, has been recorded for Benjamin Kaduk
2021-08-25
06 Warren Kumari
[Ballot comment]
This was a good, and very readable document. Thank you!

I'd *really* like to see an example showing a header with both multiple …
[Ballot comment]
This was a good, and very readable document. Thank you!

I'd *really* like to see an example showing a header with both multiple proxies *and* a message/error, something like: Proxy-Status: FooProxy, SomeCDN; error=connection_timeout
This will, I hope, reduce the chance of someone messing up and assuming either just multiple proxies *or* more info.

It seems like just extending the example in 2.1.1 (or adding a second example to that section) should be easy...
2021-08-25
06 Warren Kumari Ballot comment text updated for Warren Kumari
2021-08-25
06 Warren Kumari
[Ballot comment]
This was a good, and very readable document.

I'd *really* like to see an example showing a header with both multiple proxies *and* …
[Ballot comment]
This was a good, and very readable document.

I'd *really* like to see an example showing a header with both multiple proxies *and* a message/error, something like: Proxy-Status: FooProxy, SomeCDN; error=connection_timeout
This will, I hope, reduce the chance of someone messing up and assuming either just multiple proxies *or* more info.

It seems like just extending the example in 2.1.1 (or adding a second example to that section) should be easy...
2021-08-25
06 Warren Kumari [Ballot Position Update] New position, No Objection, has been recorded for Warren Kumari
2021-08-25
06 Zaheduzzaman Sarker [Ballot comment]
Thanks for the efforts on this document. Thanks to Magnus Westerlund for his TSVart review.
2021-08-25
06 Zaheduzzaman Sarker [Ballot Position Update] New position, No Objection, has been recorded for Zaheduzzaman Sarker
2021-08-25
06 Éric Vyncke
[Ballot comment]
Thank you for the work put into this document. This header could indeed be very useful for debugging !

Please find below  some …
[Ballot comment]
Thank you for the work put into this document. This header could indeed be very useful for debugging !

Please find below  some non-blocking COMMENT points (but replies would be appreciated).

Please also address Benno Overeinder's INTDR review at https://datatracker.ietf.org/doc/review-ietf-httpbis-proxy-status-06-intdir-telechat-overeinder-2021-08-24/

Special thanks to Tommy Pauly for his shepherd's write-up notably about the WG consensus.

I hope that this helps to improve the document,

Regards,

-éric

== COMMENTS ==

Is there any reason why a 'Proxy-Status-Request' (or similar) is not specified ?

-- Section 2 --
About "Origin servers MUST NOT generate the Proxy-Status field.", while I understand the reasoning of it, I still wonder how a 'smart gateway' (not a plain HTTP proxy but more like a content changer, such as mobile optimization by reducing IMG size, or language translation, or ...) should handle this ? As it is new content, the 'smart gateway' is the origin but getting info from the real origin could also be useful. Or is it simply over-complex ?

-- Section 2.1.2 --
Some explanations about the example would be welcome.

-- Section 2.3 --
Should there be an error type for 'too many intermediaries' ?
2021-08-25
06 Éric Vyncke [Ballot Position Update] New position, No Objection, has been recorded for Éric Vyncke
2021-08-24
06 Benno Overeinder Request for Telechat review by INTDIR Completed: Ready with Nits. Reviewer: Benno Overeinder. Review has been revised by Benno Overeinder.
2021-08-24
06 Benno Overeinder Request for Telechat review by INTDIR Completed: Ready with Nits. Reviewer: Benno Overeinder. Sent review to list.
2021-08-24
06 Barry Leiba Assignment of request for Last Call review by ARTART to Tim Bray was marked no-response
2021-08-24
06 Lars Eggert
[Ballot comment]
Section 2. , paragraph 12, comment:
>    When adding a value to the Proxy-Status field, intermediaries SHOULD
>    preserve the existing …
[Ballot comment]
Section 2. , paragraph 12, comment:
>    When adding a value to the Proxy-Status field, intermediaries SHOULD
>    preserve the existing members of the field, to allow debugging of the
>    entire chain of intermediaries handling the request.

I'm surprised this is not a MUST? Are there any valid reasons for not observing
order?

-------------------------------------------------------------------------------
All comments below are about very minor potential issues that you may choose to
address in some way - or ignore - as you see fit. Some were flagged by
automated tools (via https://github.com/larseggert/ietf-reviewtool), so there
will likely be some false positives. There is no need to let me know what you
did with these suggestions.

"Table of Contents", paragraph 2, nit:
> e critical infrastructure of many Web sites. Typically, HTTP intermediaries
>                                  ^^^^^^^^^
Nowadays, it's more common to write this as one word.

Section 2.1.1. , paragraph 6, nit:
> ed HTTP Status Code. When generating a HTTP response containing "error", its
>                                      ^
Use "an" instead of "a" if the following word starts with a vowel sound, e.g.
"an article", "an hour". (Also elsewhere.)

Section 2.1.2. , paragraph 1, nit:
>  protocol identifier is able to be expressed as an sf-token using ASCII encod
>                                ^^^^^^^^^^^^
Avoid the passive voice after "to be able to".
2021-08-24
06 Lars Eggert [Ballot Position Update] New position, No Objection, has been recorded for Lars Eggert
2021-08-23
06 Alvaro Retana [Ballot Position Update] New position, No Objection, has been recorded for Alvaro Retana
2021-08-23
06 Roman Danyliw
[Ballot comment]
Thank you to Rich Salz for the SECDIR review.

-- Editorial.  These inline URLs are being rendered as “URL (URL)”.

Section 2.1.3

  …
[Ballot comment]
Thank you to Rich Salz for the SECDIR review.

-- Editorial.  These inline URLs are being rendered as “URL (URL)”.

Section 2.1.3

  https://www.iana.org/assignments/tls-extensiontype-values/tls-
  extensiontype-values.xhtml#alpn-protocol-ids
  (https://www.iana.org/assignments/tls-extensiontype-values/tls-
  extensiontype-values.xhtml#alpn-protocol-ids)). 

Section 2.2.
  See the registry at https://iana.org/assignments/http-proxy-status
(https://iana.org/assignments/http-proxy-status)
2021-08-23
06 Roman Danyliw [Ballot Position Update] New position, No Objection, has been recorded for Roman Danyliw
2021-08-23
06 Robert Wilton [Ballot Position Update] New position, No Objection, has been recorded for Robert Wilton
2021-08-21
06 Erik Kline
[Ballot comment]
[S2.1.2, question]

* Can a port number also be expressed in this parameter (e.g., in the event
  that non-standard port numbers are …
[Ballot comment]
[S2.1.2, question]

* Can a port number also be expressed in this parameter (e.g., in the event
  that non-standard port numbers are configured)?
2021-08-21
06 Erik Kline [Ballot Position Update] New position, Yes, has been recorded for Erik Kline
2021-08-21
06 Jim Fenton Request for Last Call review by ARTART Completed: Almost Ready. Reviewer: Jim Fenton. Sent review to list.
2021-08-20
06 Martin Duke
[Ballot comment]
I'm disappointed that there isn't an end-to-end connection option to request this field. It would be a useful mode for intermediaries to only …
[Ballot comment]
I'm disappointed that there isn't an end-to-end connection option to request this field. It would be a useful mode for intermediaries to only include this field on request for performance reasons (as IIUC this is mainly about debugging).
2021-08-20
06 Martin Duke [Ballot Position Update] New position, No Objection, has been recorded for Martin Duke
2021-08-19
06 Bernie Volz Request for Telechat review by INTDIR is assigned to Benno Overeinder
2021-08-19
06 Bernie Volz Request for Telechat review by INTDIR is assigned to Benno Overeinder
2021-08-19
06 Gunter Van de Velde Request for Telechat review by OPSDIR is assigned to Ron Bonica
2021-08-19
06 Gunter Van de Velde Request for Telechat review by OPSDIR is assigned to Ron Bonica
2021-08-19
06 Éric Vyncke Requested Telechat review by INTDIR
2021-08-18
06 Barry Leiba Request for Last Call review by ARTART is assigned to Jim Fenton
2021-08-18
06 Barry Leiba Request for Last Call review by ARTART is assigned to Jim Fenton
2021-08-18
06 (System) IANA Review state changed to IANA OK - Actions Needed from Version Changed - Review Needed
2021-08-17
06 Cindy Morgan Placed on agenda for telechat - 2021-08-26
2021-08-16
06 Francesca Palombini Ballot has been issued
2021-08-16
06 Francesca Palombini [Ballot Position Update] New position, Yes, has been recorded for Francesca Palombini
2021-08-16
06 Francesca Palombini Created "Approve" ballot
2021-08-16
06 Francesca Palombini IESG state changed to IESG Evaluation from Waiting for AD Go-Ahead
2021-08-16
06 (System) IANA Review state changed to Version Changed - Review Needed from IANA OK - Actions Needed
2021-08-16
06 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-06.txt
2021-08-16
06 (System) New version approved
2021-08-16
06 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-08-16
06 Mark Nottingham Uploaded new revision
2021-08-11
05 (System) IESG state changed to Waiting for AD Go-Ahead from In Last Call
2021-08-10
05 (System) IANA Review state changed to IANA OK - Actions Needed from IANA - Review Needed
2021-08-10
05 Sabrina Tanamal
(Via drafts-lastcall@iana.org): IESG/Authors/WG Chairs:

The IANA Functions Operator has completed its review of draft-ietf-httpbis-proxy-status-05. If any part of this review is inaccurate, please let …
(Via drafts-lastcall@iana.org): IESG/Authors/WG Chairs:

The IANA Functions Operator has completed its review of draft-ietf-httpbis-proxy-status-05. If any part of this review is inaccurate, please let us know.

The IANA Functions Operator has a question about one of the actions requested in the IANA Considerations section of this document.

The IANA Functions Operator understands that, upon approval of this document, there are two actions which we must complete.

First, a new registry is to be created called the HTTP Proxy-Status Parameters registry on a new registry page at:

https://iana.org/assignments/http-proxy-statuses/

IANA Question --> What should the new registry page be named?

The registration policy for the new registry is Expert Review as defined in RFC 8126.

There are initial registrations in the new registry as follows:

Name: error
Description: The "error" parameter's value is an sf-token that is a Proxy Error Type. When present, it indicates that the proxy encountered an issue when obtaining a response.
Reference: [ RFC-to-be ]

Name: next-hop
Description: The "next-hop" parameter's value is an sf-string or sf-token that identifies the intermediary or origin server selected (and used, if contacted) for this response. It might be a hostname, IP address, or alias.
Reference: [ RFC-to-be ]

Name: next-protocol
Description: The "next-protocol" parameter's value indicates the ALPN protocol
identifier [RFC7301] used by the intermediary to connect to the next
hop. This is only applicable when that connection was actually established.
Reference: [ RFC-to-be ]

Name: received-status
Description: The "received-status" parameter's value indicates the HTTP status code that the intermediary received from the next hop server.
Reference: [ RFC-to-be ]

Name: details
Description: The "details" parameter's value is an sf-string containing additional information not captured anywhere else. This can include implementation-specific or deployment-specific information.
Reference: [ RFC-to-be ]

Second, a new registry is to be created called the HTTP Proxy Error Types registry on a new registry page at:

https://iana.org/assignments/http-proxy-statuses/

The registration policy for the new registry is Expert Review as defined in RFC 8126.

There are thirty-two initial registrations in the new registry as follows:

Name: dns_timeout
Description: The intermediary encountered a timeout when trying to find an IP address for the next hop hostname.
Reference: [ RFC-to-be ]

Name :dns_error
Description: The intermediary encountered a DNS error when trying to find an IP address for the next hop hostname.
Reference: [ RFC-to-be ]

Name: destination_not_found
Description: The intermediary cannot determine the appropriate next hop to use for this request; for example, it may not be configured. Note that this error is specific to gateways, which typically require specific configuration to identify the "backend" server; forward proxies use in-band information to identify the origin server.
Reference: [ RFC-to-be ]

Name: destination_unavailable
Description: The intermediary considers the next hop to be unavailable; e.g., recent attempts to communicate with it may have failed, or a health check may indicate that it is down.
Reference: [ RFC-to-be ]

Name: destination_ip_prohibited
Description: The intermediary is configured to prohibit connections to the next hop IP address.
Reference: [ RFC-to-be ]

Name: destination_ip_unroutable
Description: The intermediary cannot find a route to the next hop IP address.
Reference: [ RFC-to-be ]

Name: connection_refused
Description: The intermediary's connection to the next hop was refused.
Reference: [ RFC-to-be ]

Name: connection_terminated
Description: The intermediary's connection to the next hop was closed before complete response was received.
Reference: [ RFC-to-be ]

Name: connection_timeout
Description: The intermediary's attempt to open a connection to the next hop timed out.
Reference: [ RFC-to-be ]

Name: connection_read_timeout
Description: The intermediary was expecting data on a connection (e.g., part of a response), but did not receive any new data in a configured time limit.
Reference: [ RFC-to-be ]

Name: connection_write_timeout
Description: The intermediary was attempting to write data to a connection, but was not able to (e.g., because its buffers were full).
Reference: [ RFC-to-be ]

Name: connection_limit_reached
Description: The intermediary is configured to limit the number of connections it has to the next hop, and that limit has been passed.
Reference: [ RFC-to-be ]

Name: tls_protocol_error
Description: The intermediary encountered a TLS error when communicating with the next hop, either during handshake or afterwards.
Reference: [ RFC-to-be ]

Name: tls_certificate_error
Description: The intermediary encountered an error when verifying the certificate presented by the next hop.
Reference: [ RFC-to-be ]

Name: tls_alert_received
Description: The intermediary received a TLS alert from the next hop.
Reference: [ RFC-to-be ]

Name: http_request_error
Description: The intermediary is generating a client (4xx) response on the origin's behalf. Applicable status codes include (but are not limited to) 400, 403, 405, 406, 408, 411, 413, 414, 415, 416, 417, 429.
Reference: [ RFC-to-be ]

Name: http_request_denied
Description: The intermediary rejected the HTTP request based on its configuration and/or policy settings. The request wasn't forwarded to the next hop.
Reference: [ RFC-to-be ]

Name: http_response_incomplete
Description: The intermediary received an incomplete response to the request from the next hop.
Reference: [ RFC-to-be ]

Name: http_response_header_section_size
Description: The intermediary received a response to the request whose header section was considered too large.
Reference: [ RFC-to-be ]

Name: http_response_header_size
Description: The intermediary received a response to the request containing an individual header line that was considered too large.
Reference: [ RFC-to-be ]

Name: http_response_body_size
Description: The intermediary received a response to the request whose body was considered too large.
Reference: [ RFC-to-be ]

Name: http_response_trailer_section_size
Description: The intermediary received a response to the request whose trailer section was considered too large.
Reference: [ RFC-to-be ]

Name: http_response_trailer_size
Description: The intermediary received a response to the request containing an individual trailer line that was considered too large.
Reference: [ RFC-to-be ]

Name: http_response_transfer_coding
Description: The intermediary encountered an error decoding the transfer-coding of the response.
Reference: [ RFC-to-be ]

Name: http_response_content_coding
Description: The intermediary encountered an error decoding the content-coding of the response.
Reference: [ RFC-to-be ]

Name: http_response_timeout
Description: The intermediary reached a configured time limit waiting for the complete response.
Reference: [ RFC-to-be ]

Name: http_upgrade_failed
Description: The HTTP Upgrade between the intermediary and the next hop failed.
Reference: [ RFC-to-be ]

Name: http_protocol_error
Description: The intermediary encountered a HTTP protocol error when communicating with the next hop. This error should only be used when a more specific one is not defined.
Reference: [ RFC-to-be ]

Name: proxy_internal_response
Description: The intermediary generated the response locally, without attempting to connect to the next hop (e.g. in response to a request to a debug endpoint terminated at the intermediary).
Reference: [ RFC-to-be ]

Name: proxy_internal_error
Description: The intermediary encountered an internal error unrelated to the origin.
Reference: [ RFC-to-be ]

Name: proxy_configuration_error
Description: The intermediary encountered an error regarding its configuration.
Reference: [ RFC-to-be ]

Name: proxy_loop_detected
Description: The intermediary tried to forward the request to itself, or a loop has been detected using different means (e.g. [RFC8586]).
Reference: [ RFC-to-be ]

The IANA Functions Operator understands that these are the only actions required to be completed upon approval of this document.

Note:  The actions requested in this document will not be completed until the document has been approved for publication as an RFC. This message is meant only to confirm the list of actions that will be performed.

Thank you,

Sabrina Tanamal
Lead IANA Services Specialist
2021-08-04
05 Magnus Westerlund Request for Last Call review by TSVART Completed: Ready with Issues. Reviewer: Magnus Westerlund. Sent review to list.
2021-07-28
05 Thomas Fossati Request for Last Call review by GENART Completed: Ready with Nits. Reviewer: Thomas Fossati. Sent review to list.
2021-07-27
05 Barry Leiba Request for Last Call review by ARTART is assigned to Tim Bray
2021-07-27
05 Barry Leiba Request for Last Call review by ARTART is assigned to Tim Bray
2021-07-26
05 Magnus Westerlund Request for Last Call review by TSVART is assigned to Magnus Westerlund
2021-07-26
05 Magnus Westerlund Request for Last Call review by TSVART is assigned to Magnus Westerlund
2021-07-23
05 Jean Mahoney Request for Last Call review by GENART is assigned to Thomas Fossati
2021-07-23
05 Jean Mahoney Request for Last Call review by GENART is assigned to Thomas Fossati
2021-07-22
05 Rich Salz Request for Last Call review by SECDIR Completed: Has Nits. Reviewer: Rich Salz. Sent review to list.
2021-07-22
05 Tero Kivinen Request for Last Call review by SECDIR is assigned to Rich Salz
2021-07-22
05 Tero Kivinen Request for Last Call review by SECDIR is assigned to Rich Salz
2021-07-21
05 Cindy Morgan IANA Review state changed to IANA - Review Needed
2021-07-21
05 Cindy Morgan
The following Last Call announcement was sent out (ends 2021-08-11):

From: The IESG
To: IETF-Announce
CC: draft-ietf-httpbis-proxy-status@ietf.org, francesca.palombini@ericsson.com, httpbis-chairs@ietf.org, ietf-http-wg@w3.org, tpauly@apple.com …
The following Last Call announcement was sent out (ends 2021-08-11):

From: The IESG
To: IETF-Announce
CC: draft-ietf-httpbis-proxy-status@ietf.org, francesca.palombini@ericsson.com, httpbis-chairs@ietf.org, ietf-http-wg@w3.org, tpauly@apple.com
Reply-To: last-call@ietf.org
Sender:
Subject: Last Call:  (The Proxy-Status HTTP Response Header Field) to Proposed Standard


The IESG has received a request from the HTTP WG (httpbis) to consider the
following document: - 'The Proxy-Status HTTP Response Header Field'
  as Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits final
comments on this action. Please send substantive comments to the
last-call@ietf.org mailing lists by 2021-08-11. Exceptionally, comments may
be sent to iesg@ietf.org instead. In either case, please retain the beginning
of the Subject line to allow automated sorting.

Abstract


  This document defines the Proxy-Status HTTP field to convey the
  details of intermediary response handling, including generated
  errors.




The file can be obtained via
https://datatracker.ietf.org/doc/draft-ietf-httpbis-proxy-status/



No IPR declarations have been submitted directly on this I-D.




2021-07-21
05 Cindy Morgan IESG state changed to In Last Call from Last Call Requested
2021-07-21
05 Cindy Morgan Last call announcement was changed
2021-07-21
05 Francesca Palombini Last call was requested
2021-07-21
05 Francesca Palombini Last call announcement was generated
2021-07-21
05 Francesca Palombini Ballot approval text was generated
2021-07-21
05 Francesca Palombini IESG state changed to Last Call Requested from AD Evaluation
2021-07-09
05 (System) Changed action holders to Francesca Palombini (IESG state changed)
2021-07-09
05 Francesca Palombini IESG state changed to AD Evaluation from Publication Requested
2021-07-09
05 Francesca Palombini Ballot writeup was changed
2021-07-08
05 Tommy Pauly
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated …
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header?

Proposed Standard, as indicated in the document.

(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections:

Technical Summary:

This document defines a new HTTP header that can be added to responses by intermediary proxies to report statuses and errors.

Working Group Summary:

The WG process for this document was smooth, over the past 2 years, getting decent amounts of feedback and input from the community. No major issues were raised.

Document Quality:

The document is of good quality, and seems ready for publication. Several implementations already exist and are deployed.

Personnel:

Document Shepherd: Tommy Pauly
Responsible AD: Francesca Palombini

(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG.

I reviewed this document, and am happy with the current state.

(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed?

This document, being relatively narrow, received a moderate amount of reviews, but in line with what we expect for the group.

(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place.

None specifically.

(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here.

No concerns.

(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

No IPR disclosures have been filed.

(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures.

No IPR disclosures have been filed.

(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it?

WG consensus seems clear; the document received less feedback than some of our larger documents, but was supported by the individuals engaged with this document (who also have the expertise in the topic).

(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise the areas of conflict in separate email messages to the Responsible Area Director. (It should be in a separate email because this questionnaire is publicly available.)

No discontent has been raised.

(11) Identify any ID nits the Document Shepherd has found in this document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough.

No nits found.

(12) Describe how the document meets any required formal review criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.

Not applicable.

(13) Have all references within this document been identified as either normative or informative?

Yes.

(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion?

No.

(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure.

No.

(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary.

No changes to existing RFCs.

(17) Describe the Document Shepherd's review of the IANA considerations section, especially with regard to its consistency with the body of the document. Confirm that all protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126).

The document is largely about defining a new header, which comes along with a new IANA registry to contain proxy-status fields. This is well written and clear.

(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries.

HTTP Proxy-Status Parameters registry

The HTTPbis WG should likely be consulted for selection of experts; having these experts be consistent with existing registries, such as the HTTP Cache Directive registry, would make sense.

(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.

ABNF rules are valid.

(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools (https://trac.ietf.org/trac/ops/wiki/yang-review-tools) for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?

Not applicable

2021-07-08
05 Tommy Pauly Responsible AD changed to Francesca Palombini
2021-07-08
05 Tommy Pauly IETF WG state changed to Submitted to IESG for Publication from WG Consensus: Waiting for Write-Up
2021-07-08
05 Tommy Pauly IESG state changed to Publication Requested from I-D Exists
2021-07-08
05 Tommy Pauly IESG process started in state Publication Requested
2021-07-08
05 Tommy Pauly Tag Revised I-D Needed - Issue raised by WGLC cleared.
2021-07-08
05 Tommy Pauly
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated …
As required by RFC 4858, this is the current template for the Document
Shepherd Write-Up. Changes are expected over time.

This version is dated 1 November 2019.

(1) What type of RFC is being requested (BCP, Proposed Standard, Internet Standard, Informational, Experimental, or Historic)? Why is this the proper type of RFC? Is this type of RFC indicated in the title page header?

Proposed Standard, as indicated in the document.

(2) The IESG approval announcement includes a Document Announcement Write-Up. Please provide such a Document Announcement Write-Up. Recent examples can be found in the "Action" announcements for approved documents. The approval announcement contains the following sections:

Technical Summary:

This document defines a new HTTP header that can be added to responses by intermediary proxies to report statuses and errors.

Working Group Summary:

The WG process for this document was smooth, over the past 2 years, getting decent amounts of feedback and input from the community. No major issues were raised.

Document Quality:

The document is of good quality, and seems ready for publication. Several implementations already exist and are deployed.

Personnel:

Document Shepherd: Tommy Pauly
Responsible AD: Francesca Palombini

(3) Briefly describe the review of this document that was performed by the Document Shepherd. If this version of the document is not ready for publication, please explain why the document is being forwarded to the IESG.

I reviewed this document, and am happy with the current state.

(4) Does the document Shepherd have any concerns about the depth or breadth of the reviews that have been performed?

This document, being relatively narrow, received a moderate amount of reviews, but in line with what we expect for the group.

(5) Do portions of the document need review from a particular or from broader perspective, e.g., security, operational complexity, AAA, DNS, DHCP, XML, or internationalization? If so, describe the review that took place.

None specifically.

(6) Describe any specific concerns or issues that the Document Shepherd has with this document that the Responsible Area Director and/or the IESG should be aware of? For example, perhaps he or she is uncomfortable with certain parts of the document, or has concerns whether there really is a need for it. In any event, if the WG has discussed those issues and has indicated that it still wishes to advance the document, detail those concerns here.

No concerns.

(7) Has each author confirmed that any and all appropriate IPR disclosures required for full conformance with the provisions of BCP 78 and BCP 79 have already been filed. If not, explain why?

No IPR disclosures have been filed.

(8) Has an IPR disclosure been filed that references this document? If so, summarize any WG discussion and conclusion regarding the IPR disclosures.

No IPR disclosures have been filed.

(9) How solid is the WG consensus behind this document? Does it represent the strong concurrence of a few individuals, with others being silent, or does the WG as a whole understand and agree with it?

WG consensus seems clear; the document received less feedback than some of our larger documents, but was supported by the individuals engaged with this document (who also have the expertise in the topic).

(10) Has anyone threatened an appeal or otherwise indicated extreme discontent? If so, please summarise the areas of conflict in separate email messages to the Responsible Area Director. (It should be in a separate email because this questionnaire is publicly available.)

No discontent has been raised.

(11) Identify any ID nits the Document Shepherd has found in this document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts Checklist). Boilerplate checks are not enough; this check needs to be thorough.

No nits found.

(12) Describe how the document meets any required formal review criteria, such as the MIB Doctor, YANG Doctor, media type, and URI type reviews.

Not applicable.

(13) Have all references within this document been identified as either normative or informative?

Yes.

(14) Are there normative references to documents that are not ready for advancement or are otherwise in an unclear state? If such normative references exist, what is the plan for their completion?

No.

(15) Are there downward normative references references (see RFC 3967)? If so, list these downward references to support the Area Director in the Last Call procedure.

No.

(16) Will publication of this document change the status of any existing RFCs? Are those RFCs listed on the title page header, listed in the abstract, and discussed in the introduction? If the RFCs are not listed in the Abstract and Introduction, explain why, and point to the part of the document where the relationship of this document to the other RFCs is discussed. If this information is not in the document, explain why the WG considers it unnecessary.

No changes to existing RFCs.

(17) Describe the Document Shepherd's review of the IANA considerations section, especially with regard to its consistency with the body of the document. Confirm that all protocol extensions that the document makes are associated with the appropriate reservations in IANA registries. Confirm that any referenced IANA registries have been clearly identified. Confirm that newly created IANA registries include a detailed specification of the initial contents for the registry, that allocations procedures for future registrations are defined, and a reasonable name for the new registry has been suggested (see RFC 8126).

The document is largely about defining a new header, which comes along with a new IANA registry to contain proxy-status fields. This is well written and clear.

(18) List any new IANA registries that require Expert Review for future allocations. Provide any public guidance that the IESG would find useful in selecting the IANA Experts for these new registries.

HTTP Proxy-Status Parameters registry

The HTTPbis WG should likely be consulted for selection of experts; having these experts be consistent with existing registries, such as the HTTP Cache Directive registry, would make sense.

(19) Describe reviews and automated checks performed by the Document Shepherd to validate sections of the document written in a formal language, such as XML code, BNF rules, MIB definitions, YANG modules, etc.

ABNF rules are valid.

(20) If the document contains a YANG module, has the module been checked with any of the recommended validation tools (https://trac.ietf.org/trac/ops/wiki/yang-review-tools) for syntax and formatting validation? If there are any resulting errors or warnings, what is the justification for not fixing them at this time? Does the YANG module comply with the Network Management Datastore Architecture (NMDA) as specified in RFC8342?

Not applicable

2021-07-08
05 Tommy Pauly Notification list changed to tpauly@apple.com because the document shepherd was set
2021-07-08
05 Tommy Pauly Document shepherd changed to Tommy Pauly
2021-04-27
05 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-05.txt
2021-04-27
05 (System) New version approved
2021-04-27
05 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-04-27
05 Mark Nottingham Uploaded new revision
2021-04-27
04 Tommy Pauly Tag Revised I-D Needed - Issue raised by WGLC set.
2021-04-27
04 Tommy Pauly IETF WG state changed to WG Consensus: Waiting for Write-Up from In WG Last Call
2021-04-27
04 Tommy Pauly Changed consensus to Yes from Unknown
2021-04-27
04 Tommy Pauly Intended Status changed to Proposed Standard from None
2021-04-08
04 Tommy Pauly IETF WG state changed to In WG Last Call from WG Document
2021-02-09
04 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-04.txt
2021-02-09
04 (System) New version approved
2021-02-09
04 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-02-09
04 Mark Nottingham Uploaded new revision
2021-02-09
03 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-03.txt
2021-02-09
03 (System) New version approved
2021-02-09
03 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2021-02-09
03 Mark Nottingham Uploaded new revision
2020-08-11
02 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-02.txt
2020-08-11
02 (System) New version approved
2020-08-11
02 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2020-08-11
02 Mark Nottingham Uploaded new revision
2020-08-11
02 Mark Nottingham Uploaded new revision
2020-03-01
01 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-01.txt
2020-03-01
01 (System) New version approved
2020-03-01
01 (System) Request for posting confirmation emailed to previous authors: Mark Nottingham , Piotr Sikora
2020-03-01
01 Mark Nottingham Uploaded new revision
2020-03-01
01 Mark Nottingham Uploaded new revision
2019-11-18
00 (System) Document has expired
2019-08-12
00 Mark Nottingham This document now replaces draft-nottingham-proxy-status instead of None
2019-05-06
00 Mark Nottingham New version available: draft-ietf-httpbis-proxy-status-00.txt
2019-05-06
00 (System) WG -00 approved
2019-05-02
00 Mark Nottingham Set submitter to "Mark Nottingham " and sent approval email to group chairs: httpbis-chairs@ietf.org
2019-05-02
00 Mark Nottingham Uploaded new revision