Internet Engineering Task Force (IETF)                        J. Reschke
Request for Comments: 7617                                    greenbytes
Obsoletes: 2617                                           September 2015
Category: Standards Track
ISSN: 2070-1721


                The 'Basic' HTTP Authentication Scheme

Abstract

  This document defines the "Basic" Hypertext Transfer Protocol (HTTP)
  authentication scheme, which transmits credentials as user-id/
  password pairs, encoded using Base64.

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 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7617.























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RFC 7617           'Basic' HTTP Authentication Scheme     September 2015


Copyright Notice

  Copyright (c) 2015 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
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
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  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

  This document may contain material from IETF Documents or IETF
  Contributions published or made publicly available before November
  10, 2008.  The person(s) controlling the copyright in some of this
  material may not have granted the IETF Trust the right to allow
  modifications of such material outside the IETF Standards Process.
  Without obtaining an adequate license from the person(s) controlling
  the copyright in such materials, this document may not be modified
  outside the IETF Standards Process, and derivative works of it may
  not be created outside the IETF Standards Process, except to format
  it for publication as an RFC or to translate it into languages other
  than English.

Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
    1.1.  Terminology and Notation  . . . . . . . . . . . . . . . .   3
  2.  The 'Basic' Authentication Scheme . . . . . . . . . . . . . .   3
    2.1.  The 'charset' auth-param  . . . . . . . . . . . . . . . .   5
    2.2.  Reusing Credentials . . . . . . . . . . . . . . . . . . .   7
  3.  Internationalization Considerations . . . . . . . . . . . . .   8
  4.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
  5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
  6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
    6.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
    6.2.  Informative References  . . . . . . . . . . . . . . . . .  11
  Appendix A.  Changes from RFC 2617  . . . . . . . . . . . . . . .  13
  Appendix B.  Deployment Considerations for the 'charset'
               Parameter  . . . . . . . . . . . . . . . . . . . . .  13
    B.1.  User Agents . . . . . . . . . . . . . . . . . . . . . . .  13
    B.2.  Servers . . . . . . . . . . . . . . . . . . . . . . . . .  13
    B.3.  Why not simply switch the default encoding to UTF-8?  . .  14
  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  14
  Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  15



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1.  Introduction

  This document defines the "Basic" Hypertext Transfer Protocol (HTTP)
  authentication scheme, which transmits credentials as user-id/
  password pairs, encoded using Base64 (HTTP authentication schemes are
  defined in [RFC7235]).

  This scheme is not considered to be a secure method of user
  authentication unless used in conjunction with some external secure
  system such as TLS (Transport Layer Security, [RFC5246]), as the
  user-id and password are passed over the network as cleartext.

  The "Basic" scheme previously was defined in Section 2 of [RFC2617].
  This document updates the definition, and also addresses
  internationalization issues by introducing the 'charset'
  authentication parameter (Section 2.1).

  Other documents updating RFC 2617 are "Hypertext Transfer Protocol
  (HTTP/1.1): Authentication" ([RFC7235], defining the authentication
  framework), "HTTP Digest Access Authentication" ([RFC7616], updating
  the definition of the "Digest" authentication scheme), and "HTTP
  Authentication-Info and Proxy-Authentication-Info Response Header
  Fields" ([RFC7615]).  Taken together, these four documents obsolete
  RFC 2617.

1.1.  Terminology and Notation

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in [RFC2119].

  The terms "protection space" and "realm" are defined in Section 2.2
  of [RFC7235].

  The terms "(character) repertoire" and "character encoding scheme"
  are defined in Section 2 of [RFC6365].

2.  The 'Basic' Authentication Scheme

  The Basic authentication scheme is based on the model that the client
  needs to authenticate itself with a user-id and a password for each
  protection space ("realm").  The realm value is a free-form string
  that can only be compared for equality with other realms on that
  server.  The server will service the request only if it can validate
  the user-id and password for the protection space applying to the
  requested resource.





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  The Basic authentication scheme utilizes the Authentication Framework
  as follows.

  In challenges:

  o  The scheme name is "Basic".

  o  The authentication parameter 'realm' is REQUIRED ([RFC7235],
     Section 2.2).

  o  The authentication parameter 'charset' is OPTIONAL (see
     Section 2.1).

  o  No other authentication parameters are defined -- unknown
     parameters MUST be ignored by recipients, and new parameters can
     only be defined by revising this specification.

  See also Section 4.1 of [RFC7235], which discusses the complexity of
  parsing challenges properly.

  Note that both scheme and parameter names are matched case-
  insensitively.

  For credentials, the "token68" syntax defined in Section 2.1 of
  [RFC7235] is used.  The value is computed based on user-id and
  password as defined below.

  Upon receipt of a request for a URI within the protection space that
  lacks credentials, the server can reply with a challenge using the
  401 (Unauthorized) status code ([RFC7235], Section 3.1) and the
  WWW-Authenticate header field ([RFC7235], Section 4.1).

  For instance:

     HTTP/1.1 401 Unauthorized
     Date: Mon, 04 Feb 2014 16:50:53 GMT
     WWW-Authenticate: Basic realm="WallyWorld"

  where "WallyWorld" is the string assigned by the server to identify
  the protection space.

  A proxy can respond with a similar challenge using the 407 (Proxy
  Authentication Required) status code ([RFC7235], Section 3.2) and the
  Proxy-Authenticate header field ([RFC7235], Section 4.3).







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  To receive authorization, the client

  1.  obtains the user-id and password from the user,

  2.  constructs the user-pass by concatenating the user-id, a single
      colon (":") character, and the password,

  3.  encodes the user-pass into an octet sequence (see below for a
      discussion of character encoding schemes),

  4.  and obtains the basic-credentials by encoding this octet sequence
      using Base64 ([RFC4648], Section 4) into a sequence of US-ASCII
      characters ([RFC0020]).

  The original definition of this authentication scheme failed to
  specify the character encoding scheme used to convert the user-pass
  into an octet sequence.  In practice, most implementations chose
  either a locale-specific encoding such as ISO-8859-1 ([ISO-8859-1]),
  or UTF-8 ([RFC3629]).  For backwards compatibility reasons, this
  specification continues to leave the default encoding undefined, as
  long as it is compatible with US-ASCII (mapping any US-ASCII
  character to a single octet matching the US-ASCII character code).

  The user-id and password MUST NOT contain any control characters (see
  "CTL" in Appendix B.1 of [RFC5234]).

  Furthermore, a user-id containing a colon character is invalid, as
  the first colon in a user-pass string separates user-id and password
  from one another; text after the first colon is part of the password.
  User-ids containing colons cannot be encoded in user-pass strings.

  Note that many user agents produce user-pass strings without checking
  that user-ids supplied by users do not contain colons; recipients
  will then treat part of the username input as part of the password.

  If the user agent wishes to send the user-id "Aladdin" and password
  "open sesame", it would use the following header field:

     Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==

2.1.  The 'charset' auth-param

  In challenges, servers can use the 'charset' authentication parameter
  to indicate the character encoding scheme they expect the user agent
  to use when generating "user-pass" (a sequence of octets).  This
  information is purely advisory.





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  The only allowed value is "UTF-8"; it is to be matched case-
  insensitively (see [RFC2978], Section 2.3).  It indicates that the
  server expects character data to be converted to Unicode
  Normalization Form C ("NFC"; see Section 3 of [RFC5198]) and to be
  encoded into octets using the UTF-8 character encoding scheme
  ([RFC3629]).

  For the user-id, recipients MUST support all characters defined in
  the "UsernameCasePreserved" profile defined in Section 3.3 of
  [RFC7613], with the exception of the colon (":") character.

  For the password, recipients MUST support all characters defined in
  the "OpaqueString" profile defined in Section 4.2 of [RFC7613].

  Other values are reserved for future use.

     Note: The 'charset' is only defined on challenges, as Basic
     authentication uses a single token for credentials ('token68'
     syntax); thus, the credentials syntax isn't extensible.

     Note: The name 'charset' has been chosen for consistency with
     Section 2.1.1 of [RFC2831].  A better name would have been
     'accept-charset', as it is not about the message it appears in,
     but the server's expectation.

  In the example below, the server prompts for authentication in the
  "foo" realm, using Basic authentication, with a preference for the
  UTF-8 character encoding scheme:

     WWW-Authenticate: Basic realm="foo", charset="UTF-8"

  Note that the parameter value can be either a token or a quoted
  string; in this case, the server chose to use the quoted-string
  notation.

  The user's name is "test", and the password is the string "123"
  followed by the Unicode character U+00A3 (POUND SIGN).  Using the
  character encoding scheme UTF-8, the user-pass becomes:

     't' 'e' 's' 't' ':' '1' '2' '3' pound
     74  65  73  74  3A  31  32  33  C2  A3

  Encoding this octet sequence in Base64 ([RFC4648], Section 4) yields:

     dGVzdDoxMjPCow==






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  Thus, the Authorization header field would be:

     Authorization: Basic dGVzdDoxMjPCow==

  Or, for proxy authentication:

     Proxy-Authorization: Basic dGVzdDoxMjPCow==

2.2.  Reusing Credentials

  Given the absolute URI ([RFC3986], Section 4.3) of an authenticated
  request, the authentication scope of that request is obtained by
  removing all characters after the last slash ("/") character of the
  path component ("hier_part"; see [RFC3986], Section 3).  A client
  SHOULD assume that resources identified by URIs with a prefix-match
  of the authentication scope are also within the protection space
  specified by the realm value of that authenticated request.

  A client MAY preemptively send the corresponding Authorization header
  field with requests for resources in that space without receipt of
  another challenge from the server.  Similarly, when a client sends a
  request to a proxy, it MAY reuse a user-id and password in the Proxy-
  Authorization header field without receiving another challenge from
  the proxy server.

  For example, given an authenticated request to:

     http://example.com/docs/index.html

  requests to the URIs below could use the known credentials:

     http://example.com/docs/
     http://example.com/docs/test.doc
     http://example.com/docs/?page=1

  while the URIs

     http://example.com/other/
     https://example.com/docs/

  would be considered to be outside the authentication scope.

  Note that a URI can be part of multiple authentication scopes (such
  as "http://example.com/" and "http://example.com/docs/").  This
  specification does not define which of these should be treated with
  higher priority.





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3.  Internationalization Considerations

  User-ids or passwords containing characters outside the US-ASCII
  character repertoire will cause interoperability issues, unless both
  communication partners agree on what character encoding scheme is to
  be used.  Servers can use the new 'charset' parameter (Section 2.1)
  to indicate a preference of "UTF-8", increasing the probability that
  clients will switch to that encoding.

  The 'realm' parameter carries data that can be considered textual;
  however, [RFC7235] does not define a way to reliably transport non-
  US-ASCII characters.  This is a known issue that would need to be
  addressed in a revision to that specification.

4.  Security Considerations

  The Basic authentication scheme is not a secure method of user
  authentication, nor does it in any way protect the entity, which is
  transmitted in cleartext across the physical network used as the
  carrier.  HTTP does not prevent the addition of enhancements (such as
  schemes to use one-time passwords) to Basic authentication.

  The most serious flaw of Basic authentication is that it results in
  the cleartext transmission of the user's password over the physical
  network.  Many other authentication schemes address this problem.

  Because Basic authentication involves the cleartext transmission of
  passwords, it SHOULD NOT be used (without enhancements such as HTTPS
  [RFC2818]) to protect sensitive or valuable information.

  A common use of Basic authentication is for identification purposes
  -- requiring the user to provide a user-id and password as a means of
  identification, for example, for purposes of gathering accurate usage
  statistics on a server.  When used in this way it is tempting to
  think that there is no danger in its use if illicit access to the
  protected documents is not a major concern.  This is only correct if
  the server issues both user-id and password to the users and, in
  particular, does not allow the user to choose his or her own
  password.  The danger arises because naive users frequently reuse a
  single password to avoid the task of maintaining multiple passwords.

  If a server permits users to select their own passwords, then the
  threat is not only unauthorized access to documents on the server but
  also unauthorized access to any other resources on other systems that
  the user protects with the same password.  Furthermore, in the
  server's password database, many of the passwords may also be users'
  passwords for other sites.  The owner or administrator of such a
  system could therefore expose all users of the system to the risk of



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  unauthorized access to all those other sites if this information is
  not maintained in a secure fashion.  This raises both security and
  privacy concerns ([RFC6973]).  If the same user-id and password
  combination is in use to access other accounts, such as an email or
  health portal account, personal information could be exposed.

  Basic authentication is also vulnerable to spoofing by counterfeit
  servers.  If a user can be led to believe that she is connecting to a
  host containing information protected by Basic authentication when,
  in fact, she is connecting to a hostile server or gateway, then the
  attacker can request a password, store it for later use, and feign an
  error.  Server implementers ought to guard against this sort of
  counterfeiting; in particular, software components that can take over
  control over the message framing on an existing connection need to be
  used carefully or not at all (for instance: NPH ("Non-Parsed Header")
  scripts as described in Section 5 of [RFC3875]).

  Servers and proxies implementing Basic authentication need to store
  user passwords in some form in order to authenticate a request.
  These passwords ought to be stored in such a way that a leak of the
  password data doesn't make them trivially recoverable.  This is
  especially important when users are allowed to set their own
  passwords, since users are known to choose weak passwords and to
  reuse them across authentication realms.  While a full discussion of
  good password hashing techniques is beyond the scope of this
  document, server operators ought to make an effort to minimize risks
  to their users in the event of a password data leak.  For example,
  servers ought to avoid storing user passwords in plaintext or as
  unsalted digests.  For more discussion about modern password hashing
  techniques, see the "Password Hashing Competition"
  (<https://password-hashing.net>).

  The use of the UTF-8 character encoding scheme and of normalization
  introduces additional security considerations; see Section 10 of
  [RFC3629] and Section 6 of [RFC5198] for more information.

5.  IANA Considerations

  IANA maintains the "Hypertext Transfer Protocol (HTTP) Authentication
  Scheme Registry" ([RFC7235]) at <http://www.iana.org/assignments/
  http-authschemes>.

  The entry for the "Basic" authentication scheme has been updated to
  reference this specification.







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6.  References

6.1.  Normative References

  [RFC20]    Cerf, V., "ASCII format for network interchange", STD 80,
             RFC 20, DOI 10.17487/RFC0020, October 1969,
             <http://www.rfc-editor.org/info/rfc20>.

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <http://www.rfc-editor.org/info/rfc2119>.

  [RFC2978]  Freed, N. and J. Postel, "IANA Charset Registration
             Procedures", BCP 19, RFC 2978, DOI 10.17487/RFC2978,
             October 2000, <http://www.rfc-editor.org/info/rfc2978>.

  [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO
             10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
             2003, <http://www.rfc-editor.org/info/rfc3629>.

  [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
             Resource Identifier (URI): Generic Syntax", STD 66,
             RFC 3986, DOI 10.17487/RFC3986, January 2005,
             <http://www.rfc-editor.org/info/rfc3986>.

  [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
             Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
             <http://www.rfc-editor.org/info/rfc4648>.

  [RFC5198]  Klensin, J. and M. Padlipsky, "Unicode Format for Network
             Interchange", RFC 5198, DOI 10.17487/RFC5198, March 2008,
             <http://www.rfc-editor.org/info/rfc5198>.

  [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
             Specifications: ABNF", STD 68, RFC 5234,
             DOI 10.17487/RFC5234, January 2008,
             <http://www.rfc-editor.org/info/rfc5234>.

  [RFC6365]  Hoffman, P. and J. Klensin, "Terminology Used in
             Internationalization in the IETF", BCP 166, RFC 6365,
             DOI 10.17487/RFC6365, September 2011,
             <http://www.rfc-editor.org/info/rfc6365>.

  [RFC7235]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Authentication", RFC 7235,
             DOI 10.17487/RFC7235, June 2014,
             <http://www.rfc-editor.org/info/rfc7235>.



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  [RFC7613]  Saint-Andre, P. and A. Melnikov, "Preparation,
             Enforcement, and Comparison of Internationalized Strings
             Representing Usernames and Passwords", RFC 7613,
             DOI 10.17487/RFC7613, August 2015,
             <http://www.rfc-editor.org/info/rfc7613>.

6.2.  Informative References

  [ISO-8859-1]
             International Organization for Standardization,
             "Information technology -- 8-bit single-byte coded graphic
             character sets -- Part 1: Latin alphabet No. 1", ISO/IEC
             8859-1:1998, 1998.

  [RFC2617]  Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
             Leach, P., Luotonen, A., and L. Stewart, "HTTP
             Authentication: Basic and Digest Access Authentication",
             RFC 2617, DOI 10.17487/RFC2617, June 1999,
             <http://www.rfc-editor.org/info/rfc2617>.

  [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818,
             DOI 10.17487/RFC2818, May 2000,
             <http://www.rfc-editor.org/info/rfc2818>.

  [RFC2831]  Leach, P. and C. Newman, "Using Digest Authentication as a
             SASL Mechanism", RFC 2831, DOI 10.17487/RFC2831, May 2000,
             <http://www.rfc-editor.org/info/rfc2831>.

  [RFC3875]  Robinson, D. and K. Coar, "The Common Gateway Interface
             (CGI) Version 1.1", RFC 3875, DOI 10.17487/RFC3875,
             October 2004, <http://www.rfc-editor.org/info/rfc3875>.

  [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
             (TLS) Protocol Version 1.2", RFC 5246,
             DOI 10.17487/RFC5246, August 2008,
             <http://www.rfc-editor.org/info/rfc5246>.

  [RFC6973]  Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
             Morris, J., Hansen, M., and R. Smith, "Privacy
             Considerations for Internet Protocols", RFC 6973,
             DOI 10.17487/RFC6973, July 2013,
             <http://www.rfc-editor.org/info/rfc6973>.

  [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,
             <http://www.rfc-editor.org/info/rfc7231>.




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  [RFC7615]  Reschke, J., "HTTP Authentication-Info and Proxy-
             Authentication-Info Response Header Fields", RFC 7615,
             DOI 10.17487/RFC7615, September 2015,
             <http://www.rfc-editor.org/info/rfc7615>.

  [RFC7616]  Shekh-Yusef, R., Ed., Ahrens, D., and S. Bremer, "HTTP
             Digest Access Authentication", RFC 7616,
             DOI 10.17487/RFC7616, September 2015,
             <http://www.rfc-editor.org/info/rfc7616>.










































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RFC 7617           'Basic' HTTP Authentication Scheme     September 2015


Appendix A.  Changes from RFC 2617

  The scheme definition has been rewritten to be consistent with newer
  specifications such as [RFC7235].

  The new authentication parameter 'charset' has been added.  It is
  purely advisory, so existing implementations do not need to change,
  unless they want to take advantage of the additional information that
  previously wasn't available.

Appendix B.  Deployment Considerations for the 'charset' Parameter

B.1.  User Agents

  User agents not implementing 'charset' will continue to work as
  before, ignoring the new parameter.

  User agents that already default to the UTF-8 encoding implement
  'charset' by definition.

  Other user agents can keep their default behavior and switch to UTF-8
  when seeing the new parameter.

B.2.  Servers

  Servers that do not support non-US-ASCII characters in credentials do
  not require any changes to support 'charset'.

  Servers that need to support non-US-ASCII characters, but cannot use
  the UTF-8 character encoding scheme will not be affected; they will
  continue to function as well or as badly as before.

  Finally, servers that need to support non-US-ASCII characters and can
  use the UTF-8 character encoding scheme can opt in by specifying the
  'charset' parameter in the authentication challenge.  Clients that do
  understand the 'charset' parameter will then start to use UTF-8,
  while other clients will continue to send credentials in their
  default encoding, broken credentials, or no credentials at all.
  Until all clients are upgraded to support UTF-8, servers are likely
  to see both UTF-8 and "legacy" encodings in requests.  When
  processing as UTF-8 fails (due to a failure to decode as UTF-8 or a
  mismatch of user-id/password), a server might try a fallback to the
  previously supported legacy encoding in order to accommodate these
  legacy clients.  Note that implicit retries need to be done
  carefully; for instance, some subsystems might detect repeated login
  failures and treat them as a potential credentials-guessing attack.





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RFC 7617           'Basic' HTTP Authentication Scheme     September 2015


B.3.  Why not simply switch the default encoding to UTF-8?

  There are sites in use today that default to a local character
  encoding scheme, such as ISO-8859-1 ([ISO-8859-1]), and expect user
  agents to use that encoding.  Authentication on these sites will stop
  working if the user agent switches to a different encoding, such as
  UTF-8.

  Note that sites might even inspect the User-Agent header field
  ([RFC7231], Section 5.5.3) to decide which character encoding scheme
  to expect from the client.  Therefore, they might support UTF-8 for
  some user agents, but default to something else for others.  User
  agents in the latter group will have to continue to do what they do
  today until the majority of these servers have been upgraded to
  always use UTF-8.

Acknowledgements

  This specification takes over the definition of the "Basic" HTTP
  Authentication Scheme, previously defined in RFC 2617.  We thank John
  Franks, Phillip M. Hallam-Baker, Jeffery L. Hostetler, Scott
  D. Lawrence, Paul J. Leach, Ari Luotonen, and Lawrence C. Stewart for
  their work on that specification, from which significant amounts of
  text were borrowed.  See Section 6 of [RFC2617] for further
  acknowledgements.

  The internationalization problem with respect to the character
  encoding scheme used for user-pass was reported as a Mozilla bug back
  in the year 2000 (see
  <https://bugzilla.mozilla.org/show_bug.cgi?id=41489> and also the
  more recent <https://bugzilla.mozilla.org/show_bug.cgi?id=656213>).
  It was Andrew Clover's idea to address it using a new auth-param.

  We also thank the members of the HTTPAUTH Working Group and other
  reviewers, namely, Stephen Farrell, Roy Fielding, Daniel Kahn
  Gillmor, Tony Hansen, Bjoern Hoehrmann, Kari Hurtta, Amos Jeffries,
  Benjamin Kaduk, Michael Koeller, Eric Lawrence, Barry Leiba, James
  Manger, Alexey Melnikov, Kathleen Moriarty, Juergen Schoenwaelder,
  Yaron Sheffer, Meral Shirazipour, Michael Sweet, and Martin Thomson
  for feedback on this revision.











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RFC 7617           'Basic' HTTP Authentication Scheme     September 2015


Author's Address

  Julian F. Reschke
  greenbytes GmbH
  Hafenweg 16
  Muenster, NW  48155
  Germany

  Email: [email protected]
  URI:   http://greenbytes.de/tech/webdav/









































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