O

offsite storage

Storing data off site, usually in a secure location.

one-tier model

A model in which the database and applications exist on the same system.

one-time pad

Words added to values during authentication. The message to be encrypted is added to this random text before hashing.

onsite storage

Storing backup data at the same site as the servers on which the original data resides.

Open Shortest Path First (OSPF)

A link-state routing protocol used in IP networks.

Open Systems Interconnection (OSI) model

A model defined by the ISO to categorize the process of communication between computers in terms of seven layers. The seven layers are Application, Presentation, Session, Transport, Network, Data Link, and Physical. See also International Organization for Standardization (ISO).

operational security

Security as it relates to how an organization does things (operates).

operator

The person primarily responsible for the intrusion detection system (IDS).

OS hardening

The process of applying all security patches and fixes to an operating system to make it as secure as possible.

OSI model

See Open Systems Interconnection (OSI) model.

OSPF

See Open Shortest Path First (OSPF).

out-of-band method

A way to transmit the encryption key by using a method other than the one used to transmit the data. The key value is sent by letter, by courier, or by some other separate means.

OVAL

An acronym for Open Vulnerability and Assessment Language, it is a community standard for system analysis that focuses on testing, analyzing, and reporting.

owner

The person responsible for the current existence of a resource.