The Gate Keeper mechanism is not publicly documented.
Gate Keeper Passport is the same system, But uses parameters supplied by the HTML webpage to log you into a personal account.
What would be chat conversations without emoticons?
Here you can have a lot of naughty and rude smileys, your friends would be shocked and if you have a boyfriend or girlfriend or you are married, you can express your intentions very well.
To ensure the MSN Chat network was only being connected to by authorized clients, Microsoft created and implemented a SASL based Security Service Provider authentication package known as Gate Keeper.
This used a randomized session key to authorize users not using the Microsoft Passport (now Microsoft account) system.
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