Overview#Cross-platform Authentication (CPA) also appears as Cross-client Identity for Identity Brokering any media device with an Digital Subject.
Cross-platform Authentication is often used to facilitate delivery of personalized services to the Digital Subject regardless of the device used. Of course many times this ability is used in an less appropriate manner.
Generic Security Service Application Program Interface is one Cross-platform Authentication which can be implemented over HTTP using Simple and Protected GSSAPI Negotiation Mechanism.
Often an Authentication Agent would be used to implement Cross-platform Authentication