安全断言标记语言

content: 在将身份主张发送给服务提供者之前,身份提供者也可能向委托人要求一些信息——例如用户名和密码,以验证委托人的身份。SAML规范了三方之间的主张,尤其是主张身份消息是由身份提供者传递给服务提供者。在SAML中,一个身份提供者可能提供SAML主张给许多服务提供者。同样的,一个服务提供者可以依赖并信任许多独立的身份提供者的主张。  SAML没有规定身份提供者的身份验证方法;他们大多使用用户名和密码,但也有其他验证方式,包括采用多重要素验证。诸如轻型目录访问协议、RADIUS和Active Directory等目录服务允许用户使用一组用户名和密码登录,这是身份提供者使用身份验证令牌的一个典型来源。许多流行的互联网社交网络服务也提供身份验证服务,理论上他们也可以支持SAML交换。
title: 历史.
content: OASIS安全服务技术委员会(SSTC)于2001年1月首次举行会议,提出“定义一个用于交换身份验证和授权的XML框架。”为完成此目标,下列知识产权在该年的头两个月内向SSTC进行了捐献:  在这项工作的基础上,OASIS于2002年11月宣布“安全主张标记语言”(SAML)V1.0规范成为一个OASIS标准。  与此同时,大型企业、非营利及政府组织的联盟Liberty Alliance提出了一个扩展SAML标准的“自由联盟统一联合框架”(ID-FF)。与其前身SAML类似,Liberty ID-FF提出了一个标准化、跨域、基于Web的单点登录框架。此外,Liberty描绘了一个“信任圈”(circle of trust),其中每个参与域被信任将准确记录识别用户的过程、所使用的身份验证类型,以及任何与生成身份验证凭据相关的策略。信任圈中的其他成员可以查验这些策略,以决定是否信任此类信息。  虽然ID-FF开发了Liberty,SSTC已开始小规模升级到SAML规范。这使得SSTC在2003年9月批准了SAML V1.1规范。在同月,Liberty将ID-FF贡献至OASIS,从而为SAML下一版本奠基。2005年3月,SAML V2.0被宣布成为一项OASIS标准。SAML V2.0意味着Liberty ID-FF及其他专有扩展的收敛,以及包括SAML本身的早期版本。大多数SAML实现支持V2.0,并也大多支持V1.1以实现向后兼容。截至2008年1月,SAML V2.0的开发已在政府、高等教育和全球商业企业中普遍存在。
title: 版本.
content: SAML自V1.0以来已进行一次重大及一次次要修订。  Liberty Alliance在2003年9月将其自由联盟统一联合框架(ID-FF)贡献至OASIS SSTC:  SAML的1.0和1.1版本很类似,仅存在微小差异。  SAML 2.0与SAML 1.1则有着实质性的差异。虽然两者都是解决相同的使用案例,但SAML 2.0与1.1并不兼容。  尽管ID-FF 1.2已作为SAML 2.0的基础贡献至OASIS,但在SAML 2.0与ID-FF 1.2之间有着一些重要的差异。尤其是尽管这两个规范同根同源,但两者并不兼容。
title: 设计.
content: SAML 建立在一些现有标准之上:  SAML很大程度上依赖超文本传输协议作为其通信协议。  SAML定义了基于XML的主张、协议、绑定和配置。术语SAML核心(SAML Core)指SAML主张的一般语法和语义,以及用于请求和在系统实体间传输这些主张的协议。SAML协议指谁来传输,而不是如何传输(后者由所选择的绑定决定)。因此SAML核心只定义了“纯粹的”SAML主张,以及SAML的请求和响应元素。  SAML绑定决定SAML请求和响应如何映射到标准的消息或通信协议。一个重要的、同步的绑定是SAML SOAP绑定。
title: 协议.
content: A SAML "protocol" describes how certain SAML elements (including assertions) are packaged within SAML request and response elements, and gives the processing rules that SAML entities must follow when producing or consuming these elements. For the most part, a SAML protocol is a simple request-response protocol.  Beyond queries, SAML 1.1 specifies no other protocols.  SAML 2.0 expands the notion of "protocol" considerably. The following protocols are described in detail in SAML 2.0 Core:  Most of these protocols are completely new in SAML 2.0.
title: 绑定.
content: A SAML "binding" is a mapping of a SAML protocol message onto standard messaging formats and/or communications protocols. For example, the SAML SOAP binding specifies how a SAML message is encapsulated in a SOAP envelope, which itself is bound to an HTTP message.  SAML 1.1 specifies just one binding, the SAML SOAP Binding. In addition to SOAP, implicit in SAML 1.1 Web Browser SSO are the precursors of the HTTP POST Binding, the HTTP Redirect Binding, and the HTTP Artifact Binding. These are not defined explicitly, however, and are only used in conjunction with SAML 1.1 Web Browser SSO. The notion of binding is not fully developed until SAML 2.0.  SAML 2.0 completely separates the binding concept from the underlying profile. In fact, there is a brand new binding specification in SAML 2.0 that defines the following standalone bindings:
title: 配置.
content: A SAML "profile" describes in detail how SAML assertions, protocols, and bindings combine to support a defined use case. The most important SAML profile is the Web Browser SSO Profile.  SAML 1.1 specifies two forms of Web Browser SSO, the Browser/Artifact Profile and the Browser/POST Profile. The latter passes assertions "by value" whereas Browser/Artifact passes assertions "by reference". As a consequence, Browser/Artifact requires a back-channel SAML exchange over SOAP. In SAML 1.1, all flows begin with a request at the identity provider for simplicity. Proprietary extensions to the basic IdP-initiated flow have been proposed (by Shibboleth, for example).  The Web Browser SSO Profile was completely refactored for SAML 2.0. Conceptually, SAML 1.1 Browser/Artifact and Browser/POST are special cases of SAML 2.0 Web Browser SSO. The latter is considerably more flexible than its SAML 1.1 counterpart due to the new "plug-and-play" binding design of SAML 2.0. Unlike previous versions, SAML 2.0 browser flows begin with a request at the service provider. This provides greater flexibility, but SP-initiated flows naturally give rise to the so-called "Identity Provider Discovery" problem, the focus of much research today. In addition to Web Browser SSO, SAML 2.0 introduces numerous new profiles:  Aside from the SAML Web Browser SSO Profile, some important third-party profiles of SAML include:  Alternatively, for increased security or privacy, messages may be passed "by reference". For example, an identity provider may supply a reference to a SAML assertion (called an "artifact") instead of transmitting the assertion directly through the user agent. Subsequently, the service provider requests the actual assertion via a back channel. Such a back-channel exchange is specified as a SOAP message exchange (SAML over SOAP over HTTP). In general, any SAML exchange over a secure back channel is conducted as a SOAP message exchange.  On the back channel, SAML specifies the use of SOAP 1.1. The use of SOAP as a binding mechanism is optional, however. Any given SAML deployment will choose whatever bindings are appropriate.

Summary: 安全主张标记语言(英语:Security Assertion Markup Language,简称SAML,发音"sam-el")是一个基于XML的开源标准数据格式,它在当事方之间交换身份验证和授权数据,尤其是在身份提供者和服务提供者之间交换。SAML是OASIS安全服务技术委员会的一个产品,始于2001年。其最近的主要更新发布于2005年,但协议的增强仍在通过附加的可选标准稳步增加。

Security Assertion Markup Language: Security Assertion Markup Language (SAML, pronounced "SAM-el") is an open standard for exchanging authentication and authorization data between parties, in particular, between an identity provider and a service provider. SAML is an XML-based markup language for security assertions (statements that service providers use to make access-control decisions). SAML is also: