If you are running an ASA with a basic license and you want to upgrade its license then you purchase a license upgrade. Cisco or a partner or a reseller should be able to help you with the license purchase. After you purchase the license you go through a process with the licensing center at Cisco and you get a new activation key. The process of putting the new activation key is pretty simeple. I have done it and did not have any problems.
does it mean, i need to purchase the license key from the above website.
and also does it means the key can only be used one time. because if i would like to downgrade and upgrade another same module of asa. so do i need to purchase another license key rather than using the same one that i purchased before
Certainly CDW is one place that you can purchase the license upgrade but it is not the only place.
The license is specific to a particular ASA and is generated using the serial number of the ASA so it will not work on a different ASA. If you want to downgrade/upgrade a different ASA then you will need to purchase an additional license.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...