NATCreates a unique opportunity to assist in the security of a network.NetBIOSUsed for name resolution and registration in Windows-based environments.Network
A group of devices connected by some means for sharing information or resources.Network Access Control (NAC)A set of standards defined by the network for clients attempting to access it. Usually, NAC requires that clients be virus free and adhere to specified policies before allowing them on the network.Network interface card (NIC)A physical device that connects computers and other network equipment to the transmission medium.Network Interface layerThe lowest level of the TCP/IP suite that is responsible for placing and removing packets on a physical network.Network-based IDS (N-IDS)An approach to an intrusion detection system (IDS); it attaches the system to a point in the network where it can monitor and report on all network traffic.Network-based IPS (N-IPS)An intrusion prevention system that is network based. To prevent the intrusion, it must first be detected (thus making it a superset of IDS), and then act accordingly.NotificationThe act of being alerted to an event.Open Shortest Path First (OSPF)A link-state routing protocol used in IP networks.Open Systems Interconnection (OSI) modelA model defined by the ISO to categorize the process of communication between computers in terms of seven layers: application, presentation, session, transport, network, data link, and physical.Operational security
Security as it relates to how an organization does things (operates).OperatorA person primarily responsible for the intrusion detection system (IDS).Packet filteringA network security mechanism that allows or restricts the flow of packets. It analyzes the incoming and outgoing packets and lets them pass or stops them at a network interface based on the source and destination addresses, ports, or protocols.Passive responseA nonactive response, such as logging. Passive response is the most common type of responseto many intrusions. In general, passive responses are the easiest to develop and implement.PATSee Port Address Translation (PAT).PingA TCP/IP utility used to test whether another host is reachable. An Internet Control Message Protocol (ICMP) request is sent to the host, which responds with a reply if it's reachable. The request times out if the host isn't reachable.Plain old telephone service (POTS)Standard telephone service, as opposed to other connection technologies like Digital SubscriberLine (DSL).Point-to-pointNetwork communication in which two devices have exclusive access to a network medium.Point-to-Point Tunneling Protocol (PPTP)Supports encapsulation in a single point-to-point environment and PPTP encapsulates and encrypts PPP packets.