SAML SSO > Definition ofIdentity Provider (IDP) and Service Provider (SP)

SAML SSO consists of three roles which are identity provider, service provider and user. An identity provider (IDP) is a trusted provider that enables users to use single sign-on to access other websites. A service provider (SP) is a website that hosts applications and grants access only to identified users with proper credentials. In Microsoft ADFS integration, SP is called the Relying Party (RP). The user or principal has a known account with the Identity Provider and SP.*

The figure below describes how these SAML roles apply in NetSuite:

Source: http://www.liferay.com/documentation/liferay-portal/6.1/user-guide/-/ai/lp-6-1-ugen15-integrating-liferay-users-into-your-enterprise-0