Lock-and-key is a traffic-filtering security feature that you can use to dynamically filter IP traffic. You configure lock-and-key by using IP dynamic extended ACLs. You can use lock-and-key in conjunction with other standard ACLs and static extended ACLs.
When you configure lock-and-key, you designate which users, whose IP traffic is normally blocked, can gain temporary access through the device. When lock-and-key is triggered, it reconfigures the interface's existing IP ACL to permit designated users to reach their designated host(s). Afterward, lock-and-key reconfigures the IP ACL to its original state until its next use.
A user can trigger lock-and-key to obtain temporary access by first using a standard Telnet session to ...