SNIA Online Dictionary

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C-H-S addressing	[Storage System] Acronym for Cylinder-Head-Sector addressing.
CA	[Data Security] Acronym for Certificate Authority.
cable plant	[Network] All of an installation's passive communications elements (e.g., optical fiber, twisted pair, coaxial cable, connectors, splices, etc.) between transmitters and receivers.
cache	[Computer System] 1. To store data temporarily for expedited access. 2. The location in which data is stored temporarily for expedited access. There are a variety of cache types. Read cache holds data in anticipation that it will be requested. Write cache holds data written by a client until it can be stored on other (typically slower) storage media such as disk or tape. See buffer, disk cache, write back cache, write through cache.
canister	[Storage System] An enclosure for one or more storage devices. A canister is usually designed to mount in a shelf or other enclosure that supplies power, cooling, and I/O interconnect services. It is used to minimize RF emissions and to simplify insertion and removal in multi-device storage subsystems. See shelf.
CAP Theorem	A hypothesis that it is impossible for a distributed system to provide Consistency, Availability, and Partition Tolerance guarantees at the same time. See eventual consistency.
capacity optimization methods	[Storage System] Methods which reduce the consumption of space required to store a data set, such as compression, data deduplication, thin provisioning, and delta snapshots. RAID 5 and RAID 6 may also be considered as capacity optimizing methods, as they use less space than ordinary mirroring to perform a necessary function: protecting data from storage device failure.
capacity optimizing system	[Storage System] A system which employs at least one capacity optimization method.
capacity planning	[General] The process of optimizing supply of a given resource to satisfy current and future demand for that resource. Common methods used for capacity planning include tracking, trending, forecasting and scenario planning to predict future demand.
carousel	[Data Recovery] A library or a component of a library in which the media are stored in and selected from a rotating assembly.
Carrier Sense Multiple Access with Collision Detection	[Network] A physical layer data transmission protocol used in some Ethernet networks.
cascading	The process of connecting two or more hubs or switches together to increase the number of ports or extend distances.
catalog	[Data Recovery], [File System] 1. [Data Recovery] A list of backed up files, directories, and the locations (media identifiers) of the backup copies. 2. [File System] A persistent data structure used by some file systems to keep track of the files they manage.
CBC	[Data Security] Acronym for Cipher Block Chaining.
CC	[Data Security] Acronym for Common Criteria.
CDB	[SCSI] Acronym for Command Descriptor Block.
CDMI	[Standards] Acronym for Cloud Data Management Interface.
CDP	[Data Recovery] Acronym for Continuous Data Protection.
CDR	Acronym for Clock and Data Recovery.
CE	[Network] Acronym for Converged Ethernet.
certificate	[Data Security] A data structure signed with a digital signature that is based on a public key and which asserts that the key belongs to a subject identified in the structure.
Certificate Authority	[Data Security] In a Public Key Infrastructure (PKI), the authority and organization responsible for issuing and revoking user certificates, and ensuring compliance with the PKI policies and procedures. The reputation of the certificate authority determines the trust that may be placed in the identity assurance provided by the certificates issued by the authority.
Certificate Revocation List	[Data Security] A time-stamped list of certificates, signed by the issuing Certification Authority, that have been revoked by that CA. The CRL is made available to entities that need to rely on a certificate for authentication.
chain of custody	[Legal] A process that tracks the movement of evidence through its collection, safeguarding, and analysis lifecycle by documenting each person who handled the evidence, the date/time it was collected or transferred, and the purpose for the transfer. [NIST SP 800-72]
challenge	[Data Security] A step in an authentication dialog that must be answered using either a secret or process assumed to be known only by the other party. A challenge can be as simple as "What's your password?" or as complex as "Send me the result of a retinal scan of your right eye."
Challenge Handshake Authentication Protocol	[Data Security] A password-based authentication protocol that uses a challenge to verify that a user has access rights to a system. A hash of the supplied password with the challenge is sent for comparison so the cleartext password is never sent over the connection.
channel	[Storage System], [Computer System] 1. The electrical circuits that sense or cause the state changes in recording media and convert between those state changes and electrical signals that can be interpreted as data bits. 2. Synonym for I/O interconnect. The term channel has other meanings in other branches of computer technology. The definitions given here are commonly used when discussing storage and networking. See device channel, I/O interconnect, host I/O bus.
character	[Network], [Computer System] 1. [Computer System] Synonym for byte. 2. [Computer System] One or more bytes that represent a single element in a character set. Examples of character sets include ASCII and UTF-8. 2. [Network] A 10-bit unit of information transmitted and received in certain protocols, consisting of 8 bits of data encoded as 10 bits using 8B/10B encoding.
checkpoint	[Data Recovery], [File System] 1. [Data Recovery] (noun) The recorded state of an application at an instant of time, including data, in-memory variables, program counter, and all other context that would be required to resume application execution from the recorded state. 2. [File System] (verb) An activity of a file system, such as the High Performance File System, (HPFS) or the Andrew File System (AFS), in which cached metadata (data about the structures of the file system) is periodically written to the file system's permanent store, allowing the file system to maintain consistency if an unexpected stop occurs.
checksum	[Data Security] A value computed across a set of data, used to detect change. A checksum is often used for error and manipulation detection.
CHS	[Hardware] Acronym for Cylinder Head Sector.
CID	[iSCSI] Acronym for Connection Identifier.
CIFS	[File System] Acronym for Common Internet File System.
CIM	[Management] Acronym for Common Information Model.
cipher	[Data Security] A cryptographic system where plaintext is rearranged through transposition and/or substitution under direction of a cryptographic key. When a cipher is applied to plaintext to produce ciphertext, the process is called encryption. When the cipher is applied to ciphertext to produce plaintext, the process is called decryption.
Cipher Block Chaining	[Data Security] A block cipher mode of operation, in which each block of plaintext is XORed with the previous ciphertext block before being encrypted, making each ciphertext block dependent on all preceding plaintext blocks.
ciphertext	[Data Security] Data that has been encrypted. See cleartext.
CKD	[Storage System] Acronym for Count-Key-Data.
Class 1	[Fibre Channel] A connection-oriented class of Fibre Channel communication service in which the entire data transfer rate of the link between two ports is dedicated for communication between the ports and not used for other purposes. Class 1 is also known as dedicated connection service, and is not widely implemented. See intermix.
Class 2	[Fibre Channel] An acknowledged connectionless Fibre Channel communication service. Class 2 multiplexes frames from one or more N_Ports or NL_Ports that are explicitly acknowledged by the receiver and notification of delivery failure is provided. This class of service includes end-to-end flow control.
Class 3	[Fibre Channel] An unacknowledged connectionless Fibre Channel communication service. Class 3 multiplexes frames from one or more N_Ports or NL_Ports and are not explicitly acknowledged. These frames are delivered on a "best effort" (e.g., a datagram service) basis.
class of service	[Network], [Fibre Channel] 1. [Network] A mechanism for managing traffic in a network by specifying message or packet priority or delivery acknowledgement. Network mechanisms include identification and grouping of data packets based on a priority label (in the packet header) or via mechanisms such as "per hop behavior", defined by the IETF's Differentiated Services. 2. [Fibre Channel] The characteristics and guarantees of the transport layer of a Fibre Channel network. Fibre Channel classes of service include acknowledged frame delivery with end to end flow control (i.e., Class 2), and packetized frame datagrams (i.e., Class 3). Different classes of service may simultaneously exist in a Fibre Channel Fabric. The form and reliability of delivery in Class 3 circuits may vary with the topology.
cleartext	[Data Security] Alternative term for plaintext. Stating that data is in cleartext implies that the data is not scrambled or rearranged, and is in its raw form.
CLI	[Computer System] Acronym for Command Line Interface.
client	[Computer System], [General] 1. An intelligent device or system that requests services from other intelligent devices, systems, or appliances. See server. 2. An asymmetric relationship with a second party (a server) in which the client initiates requests and the server responds to those requests.
clone	[Data Management] Synonym for snapshot. Clones and snapshots are full copies. See delta snapshot.
cloud auditor	[Cloud] A party trusted conduct independent assessment of cloud services, information system operations, performance and information security of the cloud implementation. [ISO/IEC 17788]
cloud carrier	[Cloud] An intermediary that provides connectivity and transport of cloud services between cloud providers and cloud consumers. [ISO/IEC 17788]
cloud consumer	[Cloud] A person or organization that uses cloud services. [ISO/IEC 17788]
Cloud Data Management Interface	[Cloud], [Standards] [Standards] A SNIA Technical Position for Data storage as a Service (DaaS). [Cloud] CDMI is an interface for both the data path and the control path of cloud storage. CDMI can also be used to manage storage in Cloud Computing deployments.
cloud infrastructure	[Cloud] A set of data processing components that can be automatically provisioned by consumers, accessed over a network and that provide secure multitenancy. [ISO/IEC 17788]
cloud provider	[Cloud] An entity responsible for making cloud services available to cloud consumers. [ISO/IEC 17788].
cloud security audit	[Cloud], [Data Security] Systematic evaluation of a cloud system by assessing how well it conforms to a set of established security criteria. [ISO/IEC 17788]
cloud service	[Cloud] A function useful to a cloud consumer provided by a cloud provider. [ISO/IEC 17788]
cloud storage	[Services] Synonym for Data storage as a Service. [ISO/IEC 17788]
cluster	[Computer System] A collection of computers that are interconnected (typically at high speeds) for the purpose of improving reliability, availability, serviceability, load balancing and/or performance. Often, clustered computers have access to a common pool of storage and run special software to coordinate the component computers' activities.
CMIP	[Management], [Network] Acronym for Common Management Information Protocol.
CMR	[Storage System] Acronym for conventional magnetic recording.
code bit	[Computer System] A bit (binary digit) of an encoded datum. Sequences of code bits make up symbols, each of which corresponds to a data element (word, byte, or other unit). For an example see 8b/10b encoding.
code violation	[Fibre Channel] The error condition that occurs when a received transmission character cannot be decoded into a valid data byte or special code using the validity checking rules specified by the transmission code.
cold backup	[Data Recovery] Synonym for offline backup. See hot backup, online backup.
cold data	[Data Management] Data that is accessed infrequently.
cold storage	[Data Management] Data storage device, system, or service used to store cold data at a cost that is at least an order of magnitude less than the cost of primary storage. Cold Storage features large capacity, energy saving and long-term data preservation, in order to achieve low-cost rather than performance.
cold swap	[Computer System] The substitution of a replacement unit (RU) in a system for a defective one, where external power must be removed from the system in order to perform the substitution. A cold swap is a physical substitution as well as a functional one. See automatic swap, hot swap, warm swap.
Command Descriptor Block	[SCSI] A sequence of bytes that defines a single SCSI command.
Command Line Interface	[Computer System] A form of human interface to intelligent devices characterized by non-directive prompting and character string user input. CLIs are used by system consoles and remote shell sessions (RSH, SSH). They are very useful for scripting and other administrative purposes.
committed data	[Storage System] Data that has been written to stable storage.
Common Criteria	[Data Security] A multi-part International Standard that is meant to be used as the basis for evaluation of security properties of IT products and systems. The CC is specified in ISO/IEC 15408-1:1999, ISO/IEC 15408-2:1999, and ISO/IEC 15408-3:1999.
Common Information Model	[Data Management], [Network] An object oriented description of the entities and relationships in a business' management environment maintained by the Distributed Management Task Force. CIM is divided into a Core Model and Common Models. The Core Model addresses high-level concepts (such as systems and devices), as well as fundamental relationships (such as dependencies). The Common Models describe specific problem domains such as computer system, network, user or device management. The Common Models are subclasses of the Core Model and may also be subclasses of each other.
Common Management Information Protocol	[Management], [Network] A network management protocol built on the Open Systems Interconnection (OSI) communication model. CMIP is more complete, and therefore larger than, SNMP.
Common Schema Definition Language	[Management] An OASIS standard language used to define a model over which an OData service acts. For more information and current state see https://www.odata.org/documentation/.
communications security	[Network], [Data Security] Protection of information while it's being transmitted, particularly via telecommunications. A particular focus of communications security is message authenticity. Communications security may include cryptography, transmission security, emission security, and physical security.
community cloud	[Cloud] A cloud infrastructure shared by several organizations and supporting a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations).
compensating control	[Data Security] A way - also known as a band-aid - of mitigating a known risk where it may not be feasible to deploy specific technical enablement.
Completion Queue Entry	[NVMe] A fixed size entry in a CQ that contains completion status for a single command.
compliance	[General], [Legal] 1. The state of being in accordance with a standard, specification, or clearly defined requirements. 2. The state of being in accordance with legal requirements. The "compliance market" is centered around storage and systems that support the retention and discovery of data as required by law or regulation.
Compliant Jitter Tolerance Pattern	[Data Communication] A test pattern for jitter testing.
compression	[General] Synonym for data compression.
compression ratio	[Storage System] A space reduction ratio that is the ratio of the size of the uncompressed data to the size of the compressed data.
compromise	[Data Security] An incident that subjects data to unauthorized disclosure, modification, destruction, or loss.
Computational Storage	[Computer System] Architectures that provide Computational Storage Functions (CSF) coupled to storage, offloading host processing or reducing data movement. These architectures enable improvements in application performance and/or infrastructure efficiency through the integration of compute resources (outside of the traditional compute & memory architecture) either directly with storage or between the host and the storage. The goal of these architectures is to enable parallel computation and/or to alleviate constraints on existing compute, memory, storage, and I/O.
Computational Storage Array	[Computer System] Storage Array that contains one or more Computational Storage Engines. Abbreviated as CSA.
Computational Storage Device	[Computer System] A Computational Storage Drive, Computational Storage Processor, or Computational Storage Array. Abbreviated as CSx.
Computational Storage Drive	[Computer System] A storage element that contains one or more Computational Storage Engines (CSE) and persistent data storage. Abbreviated as CSD.
Computational Storage Engine	[Computer System] A Component that is able to perform computation on data. The computation is defined by a Computational Storage Function (CSF). Abbreviated as CSE.
Computational Storage Function	[Computer System] Specific operations that may be configured and executed by a Computational Storage Engine (CSE). Abbreviated as CSF.
Computational Storage Processor	[Computer System] A component that contains one or more Computational Storage Engines (CSE) for an associated storage system without providing persistent data storage. Abbreviated as CSP.
Computational Storage Resource	[Computer System] Resource available for a host to provision a Computational Storage Device (CSx) that enables that CSx to be programmed to perform a Computational Storage Function (CSF). Abbreviated as CSR.
compute virtualization	[Computer System] Software that enables a single server hardware platform to support multiple concurrent instances of an operating system and applications.
computer security	[Data Security] Measures and controls that ensure confidentiality, integrity, and availability of information system assets including hardware, software, firmware, and information being processed, stored, and communicated.
computer virus	[Data Security] Malware that propagates itself by modifying other programs to include a possibly changed copy of itself and that is executed when the infected program is invoked.
computer worm	[Data Security] Malware that is a self-contained program that can propagate itself through data processing systems or computer networks.
concurrency	[Computer System] The property of overlapping in time, often in reference to the execution of I/O operations or I/O requests.
confidentiality	[Data Security] The property that data cannot be accessed by unauthorized parties. Confidentiality may be created by the use of encryption or access controls.
configuration management	[General] The management of system features and behaviors through the control of changes made to hardware, software, firmware documentation and related resources throughout the life cycle of an information system.
congestion	[Computer System] A condition that occurs when more services have been requested than are able to be delivered.
Congestion Notification	[Network] A notification mechanism that supports congestion management for long-lived data flows within network domains of constrained data transfer rate.
connection	[iSCSI] 1. Short form of dedicated connection. 2. A communication path between the initiator and target using a TCP/IP connection. In iSCSI, one or more connections make up a session. Connections carry control messages, SCSI commands, parameters, and data within iSCSI PDUs.
Connection ID	[Fibre Channel] A value that uniquely identifies an NVMe-oF/FC connection.
connection identifier	[iSCSI] An identifier generated by the initiator and sent to the target upon logging in or out, that uniquely identifies each connection within a session.
connectionless frame	[Network] A frame used in a connectionless service (i.e., Class 2, and Class 3 frames referred to individually or collectively).
connectionless integrity service	[Network], [Data Security] A security service that provides data integrity service for an individual IP datagram by detecting modification of the datagram without regard to the ordering of the datagram in a stream of datagrams.
connectionless service	[Fibre Channel] Communication between two N_Ports or NL_Ports for connectionless frames.
consistency group	[Storage System] A collection of replication sets grouped together to ensure write order consistency across all the replication sets' primary volumes. An operation on a consistency group, such as changing replication from asynchronous to synchronous, applies to all the replication sets within the consistency group, and consequently their volumes.
consistent volume	[Storage System], [File System] 1. [Storage System] A volume that satisfies the consistency criteria of the system on which it is hosted. 2. [File System] In LTFS, a volume in which all partitions are complete, and the last LTFS Index in the Index partition has a back pointer to the last LTFS Index in the data partition. If an LTFS volume is not consistent, some form of recovery may be necessary.
console	[Computer System] 1. A device for graphical or textual visual output from a computer system. 2. In systems, network and device management, an application that provides graphical and textual feedback regarding operation and status, and that may accept operator commands and input influencing operation and status. Sophisticated consoles designed for the management of many systems from one location are sometimes called enterprise management consoles.
content-agnostic data deduplication	[Storage System] A data deduplication method that does not require awareness of specific application data formats. See content-aware data deduplication.
content-aware data deduplication	[Storage System] A data deduplication method that leverages knowledge of specific application data formats. See content-agnostic data deduplication.
Continuous Data Protection	[Data Recovery] A class of mechanisms that continuously capture or track data modifications enabling recovery to previous points in time.
continuously increasing relative offset	[Network] A transmission control algorithm that requires the frames for a block of data to be transmitted strictly in order. Continuously increasing relative offset offers simpler reassembly and detection of lost frames than random relative offset. See relative offset.
control plane	[Computer System] The portion of a system that controls the operation of the system. Also see data plane.
control software	[Computer System] A body of software that provides common control and management. When it executes on a device, control software is often referred to as firmware.
controller	[Hardware], [NVMe], [Storage System], [Management] [Hardware] A device or component of a system that performs a control function. [Storage System] The control logic in an array, disk, or tape that performs command decoding and execution, host data transfer, serialization and deserialization of data, error detection and correction, and overall management of device operations. [Management] The control logic in a storage subsystem that performs command transformation and routing, aggregation (RAID, mirroring, striping, or other), high-level error recovery, and performance optimization for multiple storage devices. [NVMe] The interface between a host and an NVM subsystem.
controller based array / controller based disk array	[Storage System] A disk array whose control software executes in a disk subsystem controller.
controller cache	[Storage System] A cache that resides within a controller and whose primary purpose is to improve storage performance. See cache, disk cache, host cache.
Controlling FCF	[Fibre Channel] A Controlling Switch that supports Lossless Ethernet MACs.
Controlling Switch	[Fibre Channel] A switch ablA Fibre Channel Switch able to control a set of FCDFs in order to create a Distributed Switch to control a set of FCDFs in order to create a distributed switch.
conventional magnetic recording	[Storage System] A recording technique for storing data on an HDD where data is recorded on individual non-overlapping tracks which may be written randomly.
Converged Ethernet	[Network] A set of Ethernet technologies and protocols defined in IEEE 802.3 that combine to reduce packet loss.
converged infrastructure	[Computer System] The pooling of compute, storage, and networking resources using either common management tools or common (shared) physical resources.
copy on write	[Data Recovery] A technique for maintaining a point in time copy of a collection of data such that when a logical data location is written, a new physical location is chosen for the existing data, and the existing data is copied to that new physical location. See pointer remapping.
copyback	[Storage System] Deprecated synonym for rebuild / rebuilding.
Core N_Port_Name	A set of entities with the same Core Switch_Name that may host multiple Virtual Switches. A Core Switch may be a set of ports in a physical chassis, or in multiple physical chassis.
Core Switch	[Network], [Fibre Channel] 1. [Fibre Channel] A set of entities in a Virtual Fabric that all have the same Core Switch_Name. A Core Switch may contain multiple Virtual Switches. 2. [Network] A backbone switch (or set of switches) that act as the final aggregation layer for its network.
Core Switch_Name	[Fibre Channel] In a Virtual Fabric capable Fibre Channel Switch, the Switch_Name identifying the Core Switch.
Count Key Data	[Storage System] A disk data organization model in which the disk is assumed to consist of a fixed number of tracks, each having a maximum data capacity. Multiple records of varying length may be written on each track of a Count-Key-Data disk, and the usable capacity of each track depends on the number of records written to it. The CKD architecture derives its name from the record format, which consists of a field containing the number of bytes in the key and data fields and a record address, an optional key field by which particular records can be easily recognized, and the data itself. CKD is the storage architecture used by IBM Corporation's mainframe computer systems. See fixed block architecture.
counter measure	[Data Security] Any action, device, procedure, technique, or other measure that reduces the vulnerability of or threat to a system.
covert channel	[Data Security] An unintended and/or unauthorized communications path that can be used to transfer information in a manner that violates a security policy.
COW	[Data Recovery] Abbreviation for copy on write.
CPU	[Hardware] Acronym for Central Processing Unit.
CQ	[NVMe] Acronym for Completion Queue.
CQE	[NVMe] Acronym for Completion Queue Entry.
CRC	[Data Communication], [Storage System] Acronym for Cyclic Redundancy Check.
credentials	[Data Security] Information, passed from one entity to another, used to establish the sending entity's identity and/or access rights.
credit	[Fibre Channel] The number of receive buffers at a recipient available to receive frames from a transmitting FC_Port.
CRL	[Data Security] Acronym for Certificate Revocation List.
cryptanalysis	[Data Security] A set of operations performed in converting encrypted information to plaintext without initial knowledge of the algorithm and/or key employed in the encryption.
cryptographic algorithm	[Data Security] An algorithm whose outputs have cryptanalytic security properties with respect to its inputs, or vice versa.
cryptographic erase	[Data Security] Method of sanitization in which the encryption key for the encrypted target data is sanitized, making recovery of the decrypted target data infeasible. [ISO/IEC 27040]
cryptographic erasure	[Data Security] A method for rendering encrypted data unrecoverable by securely deleting the keying material required to decrypt the data. The encrypted data itself is not modified. The protection offered by cryptographic erasure is bounded by the work factor involved in discovering the decryption key or mounting a cryptanalytic attack on the encryption algorithm itself.
cryptographic hash function	[Data Security] A function that maps plaintext strings of any length to bit strings of fixed length, such that it is computationally infeasible to find correlations between inputs and outputs, and such that given one part of the output, but not the input, it is computationally infeasible to predict any bit of the remaining output. Cryptographic hash functions have many information security applications, notably in digital signatures, message authentication codes (MACs), and other forms of authentication. The output from a cryptographic hash function is known as a message digest or hash value.
cryptography	[Data Security] The principles, means and methods for rendering information unintelligible, and for restoring encrypted information to intelligible form.
cryptoperiod	[Data Security] The time span during which a specific key is authorized for use or in which the keys for a given system or application may remain in effect. [NIST SP 800-57 Part 1]
cryptosystem	[Data Security] A system for encrypting and decrypting data.
CSA	[Computer System] Abbreviation for Computational Storage Array.
CSD	[Computer System] Abbreviation for Computational Storage Drive.
CSDL	[Management] Acronym for Common Schema Definition Language.
CSE	[Computer System] Abbreviation for Computational Storage Engine.
CSF	[Computer System] Abbreviation for Computational Storage Function.
CSMA/CD	[Network] Acronym for Carrier Sense Multiple Access with Collision Detection.
CSP	[Computer System] Abbreviation for Computational Storage Processor.
CSR	[Computer System] Abbreviation for Computational Storage Resource.
CSx	[Computer System] Abbreviation for Computational Storage Device.
cumulative incremental backup	[Data Recovery] A backup in which all data objects modified since the last full backup are retained as the backup. To restore data when cumulative incremental backups are in use, only the latest full backup and the latest cumulative incremental backup are required. See differential incremental backup, full backup.
current running disparity	[Network], [Fibre Channel] The running disparity present at a transmitter when 8B/10B encoding of a data byte or special code is initiated, or at a receiver when 8B/10B decoding of a Transmission Character is initiated.
cut through	A switching technique that allows a routing decision to be made and acted upon as soon as the destination address of a frame is received.
cut through routing	[Network], [Fibre Channel] Synonym for cut through switching.
cut through switching	[Network], [Fibre Channel] A switching technique that allows a routing decision to be made and acted upon as soon as the destination address of a frame is received.
Cyclic Redundancy Check	[Data Communication], [Storage System] A scheme for checking the integrity of data that has been transmitted or stored and retrieved. A CRC consists of a fixed number of bits computed as a function of the data to be protected, and appended to the data. When the data is read or received, the function is recomputed, and the result is compared to that appended to the data. Cyclic redundancy checks differ from error correcting codes in that they can detect a wide range of errors, but are not capable of correcting them. See error correcting code.
Cylinder-Head-Sector	[Storage System] A form of addressing data stored on a disk in which the cylinder, head/platter combination, and relative sector number on a track are specified. See block addressing.