By default Jiglu requires a password that is a minimum of 8 characters. However, you can enforce stronger passwords if required.
Go to System settings and choose the User limits option. Change the Minimum password strength setting to a higher value and then select the Save button. The stronger the password required the more additional punctuation, mix of upper and lower-case characters and mix of letters and numbers are required. The Very strong choice usually results in needing passwords that are too unmemorable so is not normally recommended.
Note that this is only applicable when not using LDAP external authentication.