Simply message authentication
118569
Pen and Paper Authentication
145821
How can I design a secure API/Authentication for mobile apps to access a service?
12767
User recognition without cookies or local storage
131345
The SMTP server requires a secure connection or the client was not authenticated
127559
Password Authentication c++
39324
Handling browser level authentication using Selenium
151084
Can I programmatically login a user without a password?
3487
Can two people with different one time pads securely exchange a message like this?
64851
How do I programmatically log in a user with a POST request?
4703
What are the different ways that a message can be displayed to a bash shell after a user logs in?
103861
Login without HTTPS, how to secure?
52893
Simplest way to send one-line mail out via command line using gmail?
144666
Getting basic-auth username in php
15998
Email authentication without modifying DNS records
26778
Email verification for new users
116383
Practical non-image based CAPTCHA approaches?
21989
How can I programmatically reset a user's password