Layer 1 of the OSI Model
Application
Layer 2 of the OSI Model
Presentation
Layer 3 of the OSI Model
Session
Layer 4 of the OSI Model
Transport
Layer 5 of the OSI Model
Network
Layer 6 of the OSI Model
Data Link
Layer 7 of the OSI Model
Physical
A network database that contains a listing of all network resources - such as users - printers - groups - and so on.
directory
A network service that provides access to a central database of information - which contains detailed information about the resources available on a network.
directory service
A method of communication between wireless receivers.
direct-sequence (DS)
A communications technology that is used to communicate in the 802.11 standard. It accomplishes communication by adding the data that is to be transmitted to a higher-speed transmission
direct-sequence spread spectrum (DSSS)
The act of recovering data following a disaster that has destroyed the data.
disaster recovery
The procedure by which data is recovered after a disaster.
disaster recovery plan
A means of restricting access to objects based on the identity of subjects and/or groups to which they belong.
Discretionary Access Control (DAC)
Technology that keeps identical copies of data on two disks to prevent the loss of data if one disk faults.
disk mirroring
Technology that enables writing data to multiple disks simultaneously in small portions called stripes.
disk striping
A fault-tolerance solution of writing data across a number of disks and recording the parity on another. In the event any one disk fails - the data on it can be recreated by looking at the remaining data and computing parity to figure out the missing data.
disk striping with parity
A derivative of a DoS attack in which multiple hosts in multiple locations all focus on one target.
Distributed Denial of Service (DDoS) attack
Any server that performs host name-to-IP address resolution.
DNS server
An area in the DNS hierarchy that is managed as a single unit.
DNS zone
Within the Internet - this is a group of computers with shared traits and a common IP address set.
domain
The network service used in TCP/IP networks that translates host names to IP addresses.
Domain Name Service (DNS)
A host that resides on more than one network and posses more than one physical network card.
dual-homed host
A keyboard and monitor that send keystrokes to a central processing computer (typically a mainframe or minicomputer) that returns screen displays to the monitor. The unit has no processing power of its own.
dumb terminal