-: How can we increase the strength of our hashes,
especially when using them as part of our password security?
First, we can use key stretching.
Key stretching is a technique
that's used to mitigate a weaker key
by increasing its effectiveness
and thereby increasing the time needed to crack it.
When you stretch a weaker key,
the weaker key is run through an algorithm
to create a longer, more secure key
than is normally used.
And it has to be at least 128 bits long.
Many systems are going to utilize key stretching
to increase the security they provide.
Systems like Wi-Fi Protected Access,
Wi-Fi Protected Access version 2, Pretty Good Privacy,
BeCrypt, and others all use key stretching.
Another technique we can use is known as salting.
Salting is a technique of adding random data
into a one-way cryptographic hash
to help protect against password cracking techniques
like dictionary attacks, brute force attacks,
and rainbow tables.
Using a nonce is another method
to help secure a weaker password,
where a number used once, known as a nonce,
is added to the password-based authentication
to help prevent an attacker
from reusing your password
if they're able to steal it somehow.
Another good tip
to help prevent password cracking attacks is
to limit the number of login attempts
that are allowed prior to locking out the user.
Normally, you want this to be set at three attempts,
so if they enter the password incorrectly three times,
the account is going to be locked.
Yes, this can be a pain for the user.
But it does increase the security
and drastically slows down an attacker
who's trying to guess the user's password
and break into the system.
(techno music)