LDAP: Lightweight Directory Access Protocol. Protocol with which access to directory services is given, used to query, for example, certificates or e-mail addresses.

Least Privilege: Designing operational aspects of a system to operate with a minimum amount of system privilege. This reduces the authorization level at which various actions are performed and decreases the chance that a process or user with high privileges may be caused to perform unauthorized activity resulting in a security breach.

Load Balancing: Distributing processing and communications activity evenly across a computer network so that no single device is overwhelmed. Load balancing is especially important for networks where it is difficult to predict the number of requests that will be issued to a server. Busy Web sites typically employ two or more Web servers in a load balancing scheme. If one server starts to get swamped, requests are forwarded to another server with more capacity. Load balancing can also refer to the communications channels themselves.

Local Area Network (LAN): An interconnected system of computers and peripherals, LAN users share data stored on hard disks and can share printers connected to the network.

Logging: The process of storing information about events that occurred on the firewall or network.

Logic Bomb: Any program or code, generally malicious, that causes a system to lock up or fail.

Log Processing: How audit logs are processed, searched for key events, or summarized.

Log Retention: How long audit logs are retained and maintained.