Your Kerberos key is derived from your password. To ensure that users who happen to have the same password do not have the same key, Kerberos 5 incorporates more information into the key using something called a salt. The supported values for salts are as follows.
normal: The default for Kerberos Version 5
v4: The only type used by Kerberos Version 4, no salt
norealm: The same as the default, without using realm information
onlyrealm: Uses only realm information as the salt
special: Only used in very special cases; not fully supported