Question

I’m currently consider to implement a login system by using php+mysql, it haven’t got any major problem.

However, I’ve notice that, more and more site currently not only use their own login system (actually, some of them are remove their own login system), but use different social networks login system (twitter, facebook, google…just like stackoverflow).

Can someone explain what is the pros and cons of these? And if using other login, are they grab the data from the facebook (for example with facebook login) or just use it as login, to prove someone who are a real human…?

(It is great if someone can provide some php example 🙂 )

Answer 1

OpenID

stackoverflow.com uses OpenID. Jeff Atwood(Author stackoverflow) even has an article explaining why stackoverflow.com uses OpenID. But to me(also Jeff Atwood) the most important properties of these (social) logins are:

• I don’t have to store(probably insecure) the passwords anymore and that the user will have less identities(passwords) to remember.
• Even if the password get’s exposed it only has to change the password in one/that spot instead of hundred spot or it has to be smart enough to not use the same password for every site, but then it will be insane difficult to remember the passwords.

Example

For an example i would advise you to read this answer from me about OpenID.