ITSM Glossary

Welcome to our ITSM Glossary. Here you will find a list of terms relevant to technical support professionals. 

If you have questions about existing glossary terms or would like to suggest adding additional terms, just let us know. Contact HDAA




Common shorthand for a service desk's or support center's coverage or hours of operation (also written 7X24), meaning seven days per week, twenty-four hours per day, 365 days per year. Other common coverage hours are 5×8, 5×12, and 7×8.



Developed by the Institute of Electrical and Electronic Engineers (IEEE), the 802.X standards define the physical and datalink layers of LAN architectures. For example, the IEEE 802.3 standard describes the cabling and signaling for a system nearly identical to Ethernet, while the 802.11x standards describe wireless networking.


Abandon Rate

(also Abn, Abandon Rate, Abandonment Rates) The percentage of total calls received that self-release from ringing or queue before reaching a support team member.


Abandoned Call

A call in which the caller hangs up (disconnects) before an operator or analyst answers the call.


Action Plan

A document used to guide the implementation of business process improvements. It contains task assignments, resource allocations, assignments, and evaluation criteria.


Action Taken Codes

A series of pre-established codes that identify possible alternative dispositions of customer calls.


Active Line

A telecommunication line that is currently available for data transmission.



A named process, function, or task that occurs over time and has recognizable results. Activities use assigned resources to produce products and services; combined, activities form business processes.


Activity Accounting

The collection of financial and operational performance information about an enterprise's significant activities.


Activity Analysis

Breaking the activities of an enterprise down into manageable segments for detailed cost and performance analysis.


Activity Codes

Codes that support analysts enter on their phones or through the call management system to identify the types of calls they are handling. Also known as Wrap-up Codes.


Activity Dependence

The state in which an activity is intermeshed with other activities in such a way that the subsequent (i.e., dependent) activity cannot be executed until one or more outputs of other activities within the process have been received.


Activity Diagram

Graphical representation used to describe the step-by-step business and operational workflows of components in a system. An activity diagram shows the overall flow of control.


Activity Measure

A performance value assigned to an activity's primary output.


Activity Model

A graphical representation of a business process that illustrates the activities that make up a business process, at any desired level of detail. An activity model depicts the interactions between activities in terms of inputs and outputs while showing the controls placed on each activity and the types of resources assigned to each activity.


Activity Model (as-is)

An activity model that portrays how a business process is currently structured. It is used to establish a baseline for subsequent business process improvement actions or programs.


Activity Model (to-be)

An activity model that results from a redesigned business process action or program. The to-be model shows how the business process will function after the improvement action is implemented.


Activity, non-value-added

Any activity that provides a negative or zero return on the investment or allocation of resources to that activity. Within broad limits, the enterprise benefits by allocating fewer resources to non-value-added activities.


Activity, value-added

Any activity that contributes directly to the performance of a process and to the return on investment of resources; such activities cannot be eliminated without impairing the process.


Activity-based Costing (ABC)

A form of cost accounting that focuses on the costs of performing specific functions (processes, activities, tasks, etc.), rather than on the costs of organizational units. Activity-based costing may generate more accurate cost and performance information related to specific products and services than is available to managers through traditional cost accounting.


Activity-based Management

A system of management that seeks to optimize the value added activities performed by the enterprise while at the same time minimizing or eliminating the non-value-added activities, resulting in overall improvements in the enterprise's effectiveness and efficiency at serving its customers.



This acronym stands for Architecture Design, Analysis, and Planning Tool. ADAPT provides a complete picture of an information system infrastructure including computers, communication links, and devices, applications, and databases. ADAPT is based on commercial off-the-shelf (COTS) software and can be used as a management tool to support inventory control, etc.


Adherence to Schedule

A term that refers to how well analysts adhere to their assigned schedules; also referred to as compliance in some organizations.


After-call Work (ACW)

Work that is completed immediately after the conclusion of a call. After-call work often includes entering data, completing forms, or making outbound calls necessary to complete a customer transaction. During this period the analyst is unavailable for the next telephone call.



A common term used to indicate a service desk or support center employee whose primary job responsibility is responding to customer calls. These employees, which HDI calls support center analysts, typically provide first- or second-level support.


Agent Group

A collection of analysts who share a common set of skills, such as being able to handle customer complaints, reset passwords, or troubleshoot database problems. Often used when referring to call routing.


Agent Status

The mode of an agent or analyst when logged into a telephone system (e.g., Talk Time, ACW, Aux, Unavailable)


Agent-out Call

An outbound call placed by an analyst or agent.



Agile software development is a group of software development methodologies based on iterative and incremental development, where requirements and solutions evolve through collaboration between self-organizing, cross-functional teams. Agile methodologies have spread into other disciplines, such as project management. They are also referenced in DevOps.



An accounting method typically used to apportion a cost or expense based upon estimated usage or volume. For example, the cost of operating a service desk or support center is often allocated to its various customer groups based upon headcount, number of workstations, or service volumes.


Allocation Routing

See Call Allocation Routing.


Analyst (Business)

See Business Analyst.


Analyst (Support Centre)

The frontline technical support professionals who receive calls or contacts and handle tickets, and who, typically, define problems and develop procedures for resolving them. Analyst is often used interchangeably with agent and/or technician.


Analytical Modeling

A technique that uses mathematical models to predict the behavior of a configuration item or IT service. Analytical models are commonly used in capacity management and availability management.



An outbound, recorded verbal message played for callers. Also, a message posted on the support center web page or intranet.


Answered Call

A call is counted as answered when it reaches a support center professional or an interactive voice response (IVR) system, or when referring to an agent group .


Application Development

The functional group responsible for the development (programming) of applications. Often Called AppDev or Dev , as in DevOps .


Application Sizing

Helps to understand the resource requirements needed to support a new application or a major change to an existing one, and to ensure that an IT service can meet its service level targets for capacity and performance.



(1) An organized framework consisting of principles, rules, conventions, and standards that serve to guide the development and construction activities such that all components of the intended structure will work together to satisfy the structure's ultimate objective. (2) The basic design of a system, which determines the system's capacity and upgradeability, how the components work together, and how they integrate with other systems.


Arrival Time

The time a technician arrives on site in response to an incident or service request.


As-is Model

A model that represents the current state of the organization, without any specific improvements included. It can be either an activity model or a rule model.

Business Intelligence (BI)

The information, primarily from computer-based analysis of business data, used to provide historical, current, and predictive views of business operations.

Business Process Management (BPM)

The activities performed by a business or organization to optimize and adapt their processes to maximize efficiency, effectiveness, and cost. BPM is characterized by continuing and embedding process orientation in the business or organization’s culture.


Business Process Outsourcing (BPO)

Leveraging technology or specialized process vendors to provide and manage an organization’s critical and/or noncritical enterprise processes and applications. The most common examples of BPO are call centers, HR, accounting, and payroll outsourcing.


Business Process Re-engineering (BPR)

A quality management methodology through which large quality increases are achieved by radically redesigning existing organizations, business processes, and operating methods. See Process Redesign 

Best Practice

Generally-accepted, informally-standardized techniques, methods, or processes that have proven themselves over time and across multiple organizations. 


Blended Support

Models in which various components of more traditional support are mixed or varied (e.g., onshore/offshore, service desk/desktop support, internal employee support/external customer support, physical/virtual teams, and single-channel/multichannel support).



1) An impediment preventing traffic (voice or network) through a channel; 2) Callers blocked from entering a call queue. 

Bring Your Own Device/Computer/Technology (BYOD, BYOC, BYOT, BYOx)

The increasingly common practice, with or without a company or organizational policy, that allows or encourages staff to use personal computers, smartphones, tablets, or other devices in the work environment. 


Broadcast Message

A message transmitted to two or more locations on a network or to customers at multiple terminals or workstations.


BS 15000

Superseded by ISO/IEC 20000


Business Continuity Management (BCM)

Business Continuity Management (BCM) is an organization-wide discipline and a complete set of processes that identifies potential impacts which threaten an organization. It provides a capability for an effective response that safeguards the interests of its major stakeholders

Business Continuity Plan (BCP)

A plan that defines the steps required to restore business processes following a disruption. The plan will also identify the triggers for invocation, the people to involve, the communications to send, etc. IT service continuity plans form a significant part of the overall business continuity plans.

Business Impact Analysis (BIA)

The activity in business continuity management that identifies vital business functions and their dependencies. These dependencies may include suppliers, people, other business processes, IT services, etc.


Business Intelligence (BI)

The information, primarily from computer-based analysis of business data, used to provide historical, current, and predictive views of business operations.

Business Process Management (BPM)

The activities performed by a business or organization to optimize and adapt their processes to maximize efficiency, effectiveness, and cost. BPM is characterized by continuing and embedding process orientation in the business or organization’s culture.

Business Process Re-engineering (BPR)

A quality management methodology through which large quality increases are achieved by radically redesigning existing organizations, business processes, and operating methods. See Process Redesign.

Calendar Time Elapsed

The amount of time that elapses between the receipt of the support request and when it is resolved. This may include time spent on other activities, such as waiting for parts or advice, and may include or exclude holidays and weekends. 



A telephone call placed to the service desk or support center, typically from a customer that needs information or help solving a problem. Although call and problem are often used as all-encompassing terms for customer requests received from various communication channels 


Call Accounting

Used to gather and monitor information about all telephone calling patterns, particularly long distance; also monitors incoming calls. Usually a computer-based system linked to a telephone system. 


Call Allocation Routing

A method of statistically distributing calls among support centers based on historical patterns. 


Call Avoidance

Techniques used to eliminate or divert telephone calls away from a support center. These techniques can include analyzing the root cause of problems and incorporating this information into future releases, versions, operations, or services, thereby eliminating the cause.


Call Back

A return call from the service desk or support center to the customer in response to the customer's service request or as the result of a Web "Call Me" Request. 


Call Blending

Combining traditionally separate inbound and outbound agent groups into a single group of analysts responsible for handling both inbound and outbound contacts. 

Call Capture Rate (CCR)

The percentage of total calls handled by the call center. CCR figures do not include abandoned calls. 


Call Category

One of a set of pre-established classifications a call may be assigned to, such as hardware, software, or network. Call categories provide insight into the sources, types, or dispositions of calls. 


Call Center

An operation that provides information, products, and services by telephone or electronic means. Call centers may be inbound, outbound, or a combination of the two (see Call Blending ). Technical support centers and help desks are frequently referred to as call centers.


Call Control Variables

The set of criteria the ACD uses to process calls, such as routing criteria, overflow parameters, recorded announcements, and timing thresholds.


Call Cycle Time

The total time required to process a customer call, including call logging and initial diagnosis, research, resolution, follow-up, and closing the call. Note that the term call cycle time limits reporting to calls only versus all service requests. 


Call Forcing

An ACD feature that automatically delivers calls to analysts who are available and ready to take calls. They hear a notification that the call has arrived (e.g., a beep tone), but do not have to press a button to answer the call. 


Call Interval

Call volume is measured per period or interval, as defined in the service desk or support center’s ACD system. Used to measure the incoming call load in pre-established time frames (e.g., fifteen, thirty, or sixty minutes).


Call Load

Also referred to as workload , call load is the sum of the average talk time and average after-call work , multiplied by call volume , for a given period.


Call Logging

The process a support center professional performs while recording customer information in the case management system.


Call Management

Managing the information, processes, and systems used to control the flow of customer telephone requests in and out of the service desk or support center. Call management processes apply solely to customer requests received by telephone. See also Call Avoidance.


Call Management System

Software and other systems that work with automatic call distributors (ACDs) and related technologies to manage, track, and report on call volumes and other call statistics. See Automatic Call Distribution and Case Management System.


Call Metrics

Call measurements typically captured at the service desk or support center, such as daily call acceptance rates, total monthly call volume, daily ACD calls answered, delay before abandoning, delay before answering, and average daily call processing time.


Call Monitoring

The practice of listening in on live calls, primarily as an aid in training novice service desk or support center analysts and ensuring consistent customer service.


Call Parking

The ability to put a call on hold and pick it up using another device. 


Call Processing

Executing the procedural steps required to manage and record the resolution of a customer call. These steps may involve logging the call, routing the caller to another group, following up on the call, and closing the call. 


Call Processing Rate

The average length of time it takes to process a call. Reports may show daily call processing rates. 


Call Resolution Rate

The percentage of calls captured that are resolved by each support level or by the service desk or support center. See Resolution Rate , Call CaptureRate , and First Call Resolution Rate.


Call Screening

Collecting information from the customer, including contact information and details about the incident or service request . Screening does not involve resolving issues or answering questions. 


Call Type

A category used to distinguish incoming requests to a service desk. Some common call types are incident, service request, and complaint. 


Call Volume

The total number of inbound and outbound calls within some meaningful period or category.


Caller ID

A telephone service that automatically identifies the calling telephone number and displays this number at the receiving station or transfers it to an associated computer system, such as a problem management system. Also known as Automatic Caller Identification Service (ANIS).


Caller Tolerance

There are seven factors that influence caller behavior or tolerance, which “influence everything from how long callers will wait in queue to how many will abandon, how many will retry when they get busy signals, and how they will react to automation, such as voice response unit (VRU). They also affect how callers perceive the service...they are receiving."
The concept and characteristics of caller tolerance are the creation of Brad Cleveland and Julia Mayben in Call Center Management on Fast Forward (Call Center Press, 1997)


Calls in Progress

The total number of calls to a route or service that is currently online, in queue, or being handled at a peripheral device. 


Calls in Queue

A real-time report that refers to the number of calls received by the ACD system but not yet connected to an analyst.


Calls per Analyst (Agent)

The average number of calls received by an analyst within some meaningful period or category.

Calls per Period

Call volume per period . Typical periods service desks or support centers report on include hour, shift, day, week, month, quarter, and year.

Capability Maturity Model (CMM)

The CMM for software (also known as the CMM and SW-CMM) is a model used to identify best practices that help increase process maturity. The CMM was developed at the Software Engineering Institute (SEI) of Carnegie-Mellon University. In 2000, the SW-CMM was upgraded to CMMI (Capability Maturity Model Integration). The SEI no longer maintains the SW-CMM model, its associated appraisal methods, or training material.


Capability Maturity Model Integration (CMMI)

Capability Maturity Model Integration (CMMI) is a process improvement approach developed by the Software Engineering Institute (SEI) of Carnegie-Mellon University. CMMI provides organizations with the essential elements of effective processes. It can be a guide to process improvement across a project, a division, or an entire organization. CMMI helps integrate traditionally separate organizational functions, set process improvement goals and priorities, provide guidance for quality processes, and provide a point of reference for appraising current processes.Visit the CMMI Institute for more information.


Capacity Management

The process responsible for ensuring that the capacity of IT services and the IT infrastructure is able to deliver on agreed-upon service level targets in a cost effective and timely manner. Capacity management considers all of the resources required to deliver the IT service and plans for short, medium, and long-term business requirements.

Capital Costs

Fixed, one-time expenses for the purchase of assets. See also Capital Expenditure (CapEx).


Capital Expenditure (CapEx)

Investment in non-consumable assets, such as equipment.


Career Pathing

A career-planning process through which the support center or desktop support manager works with individual analysts to identify the next steps for their careers and provides the training and development support for the analysts to progress along their particular paths. 


A notation created in the case management system or software that records the customer’s problem or service request. Each case is typically assigned a number; cases may be created from phone calls, email, chat, autologging , fax, social media, text message, mobile app, walk-up (in person), or online form (web-based) transactions.


Case Management System

A software system used to capture and track information about individual contacts, incidents, service requests and customers. This is a generic term used to cover IT service management software, Customer Relationship Management software and simpler ticket management software systems. Individual entries are usually referred to as tickets.


Case-based Reasoning

A type of expert system based on solving problems or providing information using cases; the system matches similar past events and selects relevant experiences to provide successful solutions. This type of expert system is best applied to environments where a typical problem is narrow, but deep. The ability to go directly to a solution or a question deep in a diagnostic is a key advantage of case-based reasoning, since a problem that is deep in scope involves a larger number of questions. However, due to the large number of cases that must be entered to increase the breadth of the domain, case-based reasoning is most appropriate for problems with a narrow and fairly static domain.


Categorization - Knowledge Management

A hierarchy built for managing access to particular solutions or knowledge articles, popular with case management systems in the service desk and call center space. An alternative method to keyword searches for categorizing knowledge articles/solutions. Based on a three- or four-tier hierarchical structure to group knowledge articles and solutions.


Categorization - Support Center Cases

The most common categorization scheme, STEM (subject, type, element, and module), is a four-tier classification system that categorizes information from the general to the specific. For example, subject = hardware, type = desktop, element = Dell Latitude, and module

Cause-and-Effect Diagram

A tool developed by Dr. Kaoru Ishikawa to assist in root cause identification; also called an Ishikawa diagram or a fishbone diagram. 

Central Office

In non- VoIP telephony, the name given to the local telephone company’s servicing exchange or office, usually where the big switches are located.



A support center that serves multiple locations and is located at a single physical location. See Distributed and Decentralized. 


A non- VoIP telephone system usually supplied by the local telephone company. The switching equipment is located in the telephone company central office; the only equipment at the customer premises is the telephones. One of the attractions of the Centrex system is that it is rented rather than owned.


Any action resulting in a new status or value in baseline or configuration data. 

Change Advisory Board (CAB)

The designated group responsible for the assessment and planning of all changes that will have a more than a minor impact on business operations. All persons involved and all interested parties are represented on the CAB so that the entire course of events surrounding the change can be assessed and planned.

Change Management

(1) The process responsible for controlling the lifecycle of all changes. The primary objective of change management is to enable beneficial change with minimum disruption to IT services. A defined change management process minimizes interference and irregularity in  customer service levels related to the implementation of alterations in business facilities, equipment, or processes. (2) Change management is the process of developing a planned approach to change in an organization that facilitates the adoption of changes in the business and/or employee environment (organizational change).


The business practice by which a company cost center , such as the service desk or support center, charges its customer departments for the services it provides. These charges may be fixed allocations, fixed fees based on the support service provided, or charges based on length of calls or use.



Also called text chat , live chat or web chat , a support channel through which customers are connected to analysts in real time and can use instant messages to communicate.


Chief Information Officer

The typical title of the highest-ranking executive responsible for an organization’s information systems. Some organizations are establishing a position called Chief Digital Officer (CDO) with similar or broadened responsibilities.


CI Level

The lowest level at which identifiable items can still be uniquely distinguished.


Certified Information Systems Auditor qualification offered by ISACA.



Expressing the value of items by placing them in a certain order based on category, impact, and urgency. Classification can be used to support decisions concerning priorities.

C-level Officer or CxO

The generic title applied to executives with Chief in their titles, such as Chief Executive Officer, Chief Information Officer, Chief Financial Officer, etc. 



A computing paradigm that distributes the workload between personal computers and larger computers on the network. Process-intensive tasks stay on the server, which lowers network traffic congestion. This configuration takes advantage of more advanced, high-speed equipment and technology and frees up the client portion for other tasks.



The final status in the lifecycle of an incident, problem, change, ticket, case, etc. When the status is closed, no further action is taken.


Closed Call

A call is closed when the work has been completed, follow-up calls have been made to the customer, the case has been recorded in the case management system , and the work has been completed to the customer’s satisfaction.


Closed Contact

The same as a closed call , but the origin of the customer’s contact with the service desk or support center was through a contact channel other than the telephone line.



(1) The act of changing the status of an incident, problem change, etc. to closed. (2) Closure is typically the final step in the call management process. It usually requires verifying that the solution provided is acceptable to the customer, updating the record in the  case management system, recording details of the solution, and closing the case record.

Closure Code

A category that is assigned to an incident or problem before it is closed. The code identifies the cause and is intended for use in reporting and trend analysis; for example, “customer training required,” “documentation error,” “software bug,” etc. 

Cloud Computing

Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. According to the National Institute of Standards and Technology (NIST), there are four types of cloud:

Private Cloud - The cloud infrastructure is operated solely for an organization; it may be managed by either the organization or a third party and may exist on or off premises.

Community Cloud - The cloud infrastructure is shared by several organizations and supports a specific community that has shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be managed by either the organization or a third party and may exist on or off premises.

Public Cloud - The cloud infrastructure is made available to the general public or a large industry group and is owned by an organization that sells cloud services.

Hybrid Cloud - The cloud infrastructure is a composition of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting for load balancing between clouds).


A collaborative leadership activity designed to encourage growth and development, sometimes addressing employee performance issues. 


COBIT (Control Objectives for Information and Related Technology)

COBIT provides guidance and best practice for the management of IT processes. It is published by ISACA and the IT Governance Institute. Visit ISACA for more information. 


Code of Practice (COP)

A guideline that describes recommended best practices and is published by a public body or a standards organization, such as ISO or BSI . Many standards consist of a code of practice and a specification. 


Collateral Duties

Non-phone (or other channel used for customer interaction) tasks that are flexible and can be scheduled for periods when there are fewer contacts. 

Commercial, Off-the-Shelf (COTS)

Describes software that is commercially available and not developed in-house or as a custom product.


Conforming to a rule, such as a specification, policy, standard or law. Regulatory compliance describes the goal that corporations or public agencies aspire to in their efforts to ensure that personnel are aware of and take steps to comply with relevant laws and regulations. 

Component Failure Impact Analysis (CFIA)

A technique that helps to identify the impact of CI failure on IT services. A matrix is created with IT services on one edge and CIs on the other. This enables the identification of critical CIs that could cause the failure of multiple IT services and of fragile IT services that have multiple single points of failure.

Computer Telephony Integration (CTI)

Interfacing IT and telecommunications equipment within the same network architecture to facilitate efficient processing of customer contacts and optimize the use of customer support resources through the sharing of data between systems. For example, CTI typically allows a support center manager’s console to display real-time metrics, such as the number of calls in queue and service request escalations.

Concurrent Users

The number of customers able to access a piece of software concurrently (i.e., at the same time). Determining the maximum number of expected concurrent users allows a company to purchase enough software licenses to cover the “peak” number of users, rather than one license for each employee.

Conditional Routing

The capability of the ACD to route calls based on current conditions. It is based on “if-then” programming statements, such as “if the number of calls in agent Group One exceeds ten and there are at least two available agents in Group Two, then route the calls to Group Two"

Configuration Item (CI)

A component that is part of an IT infrastructure and needs to be managed in order to deliver an IT service. CIs may vary widely in complexity, size, and type, from an entire system (including all hardware, software, and documentation) to a single software module or a minor hardware component.

Configuration Management

The process that brings all components of the IT infrastructure and the related documentation under control to support the other service management processes and provide, at reasonable costs, qualitative services in the context of continuously changing user demands. 

Configuration Management Database (CMDB)

A database that provides a logical model of the IT infrastructure or a service by identifying, controlling, maintaining, and verifying the versions of CIs in existence; it contains details about the attributes and history of each CI and the important relationships between them.

Configuration Management System (CMS)

A system, which may be composed of several tools and databases, for managing and maintaining information about configuration items (CI's), including incidents, problems, changes, releases and known errors. Often called "CMS," but should not be confused with a  Content Management System, also called CMS.


Typically refers to a vendor, trainer, or other person external to the company contracted to help improve service desk or support center operations. Some service desks use this term to refer to their more senior internal support center analysts.

Dashboard Data

Refers to data from a balanced scorecard that is summarized in a brief or, "dashboard" format for review by senior managers. This data typically contains less than a dozen metrics and is designed for managers that wish to monitor a scorecard without reviewing pages of data.



A collection of stored data that is structured to allow queries and reporting. Typical data structures are either flat or relational. 


Database Administrtor (DBA)

The person responsible for the design, development, operation, security, maintenance, and use of a database . The DBA defines the rules by which data are accessed and stored.


Database Call Handling

A CTI application, whereby the ACD works in sync with a database to process calls, based on information in the database. 



A physically dispersed support organization in which the customer determines the appropriate location and phone number to call for service, depending on technology, problem type or information needed, or other criteria. See Centralized and Distributed Support Model


Decision Tree

A type of expert system comprised of a branching structure of questions and possible responses designed to lead an analyst to an appropriate solution to a customer’s problem, or to provide needed information. Decision-tree structures resemble an organizational hierarchy.



Refers to a support professional or team assigned to exclusively support a given product, service or task. 


Definitive Hardware Store (DHS)

Contains spares and stocks of hardware. One or more physical locations where hardware configuration items (CIs) are securely stored when not in use. All hardware in the DHS is under the control of change and release management and is recorded in the CMDB . The DHS contains spare parts, maintained at suitable revision levels, and may include hardware that is part of a future release.


Definitive Software Library (DSL)

One or more locations in which the definitive and approved versions of all software CIs are securely stored. The DSL may also contain associated CIs, such as licenses and documentation. The DSL is a single logical storage area, even if there are multiple locations. 


Also called queue time, delay is the time a caller spends in queue waiting for an analyst to become available. 

Delay Announcements

Recorded announcements that encourage callers to wait for an analyst to become available, remind them to have their account number or other pertinent details ready, and provide information on alternative methods of accessing support.


Delay Before Abandoning Rate

Statistics representing the service desk or support center’s abandoned calls and how long customers hold before they abandon. (See Abandon Rate and Average Speed to Abandonment ) Reports showing this rate indicate customers’ tolerance level for waiting to connect 


Delay in Queue

The total length of time calls spend in the queue , waiting for routing or service. Delay in queue can also take into consideration abandoned calls.


Delay Time

The time spent processing a contact after it arrives at a peripheral ( ACD , IVR ) but before it is either queued or presented to a support center analyst. 


Delayed Call

A call that cannot be answered immediately and is placed in queue. 


Something that must be provided to meet a commitment in a service level agreement (SLA) or a contract. Deliverable is also used in a more informal way to mean the planned output of any process.


Deming Cycle

The Plan-Do-Check-Act cycle of continuous improvement, named for W. Edwards Deming.



The software applications, computer hardware, and peripherals that reside at or on the customer’s desk.


Desktop Management Interface (DMI)

A proposed industry standard that gives computer products a unique code that facilitates the management of desktop computers, hardware and software components, and peripherals, whether they are standalone systems or linked into networks. The DMI was developed by the Distributed Management Task Force.


Desktop Support Manager

Manages a team of desktop support technicians and/or supervisors while executing the operational and tactical plans of desktop support and satisfying customer and business needs. Responsibilities may include performance management, monitoring/reporting metrics, audits, purchase approvals, and other similar job functions.

Desktop Support Team Lead (DSTL)

An advanced desktop support technician (DST) who, in addition to DST responsibilities, provides train­ing, mentoring, and/or coaching for a team of DSTs, but does not have direct staff management responsibili­ties. May have oversight responsibility for processes, project management tasks, and/or providing support to management.

Desktop Support Technician (DST)

An IT support professional who responds to incidents escalated from or assigned by the service desk that are related to customer equipment; additional skills, knowledge, tools, or authority are required. DSTs may resolve incidents remotely, at the deskside, or via equipment returns.



An emerging set of principles, methods, and practices for communication, collaboration, and integration between software development (application/software engineering) and IT operations (systems administration/infrastructure) professionals. The Dev refers to Application Development, and the Ops refers to Operations.



To determine the cause of a problem or type of information needed and the actions that must be taken to resolve it.


Diagnostic Aids

Diagnostic tools such as error log interpreters, crash analyzers, or network monitors that assist the support center analyst in rapidly isolating the cause of a caller’s problem.

Diagnostic Script

A structured set of questions used by service desk staff to ensure they ask the correct questions and to help them classify, resolve, and assign incidents . Diagnostic scripts may also be made available to users to help them diagnose and resolve their own incidents. 


Dialed Number Identification Service (DNIS)

A telephone service that automatically identifies the telephone number of a caller. The number can then be displayed at the receiving station or transferred to an associated computer system, such as a problem management system, or to an ACD for routing. 



The use of binary code—1's and 0's—to represent any type of information. Digital is the dominant format and more efficient than analog. 


Direct Costs

Costs that can be attributed to a specific service, business unit, or process.


Direct Software Library (DSL)

A secure software library where all versions of software CI's that have been accepted from the developer or supplier are held in their definitive, quality-controlled form. By necessity, this logical library may have to occupy one or more physical locations. 


Direct Time

The time an analyst spends on or off the phone that is directly related to resolving customers’ service requests.


Director of Desktop Support

The responsibilities of this role are broader than an individual desktop sup­port team. Managers of desktop support teams report to this person. This position may also be referred to as a senior manager.

Disaster Recovery Planning (DRP)

The plans, procedures, and contingencies that enable your company or support organization to set up, reconfigure, and continue to work after a disaster or during a work disruption, such as a power outage.



(1) Assigning a ticket to a technician for deskside support. (2) Passing an incident to a more appropriate resource without any diagnosis or troubleshooting. 


Dispatch Support Model

A call management function in which service desk or support center analysts determine whether the caller is entitled to service, determine the nature of the problem or type of information needed, log the call, and route the caller to the first-level support function.


Distributed Management Task Force (DMTF)

Formerly called the Desktop Management Task Force. A multivendor cooperative effort of about 300 companies, led by Intel Corp., that is developing the Desktop Management Interface.


Distributed Support Model

A service desk or support center comprised of multiple physical sites; the customer uses a single phone number for all contacts and problems and call routing is accomplished behind the scenes. This is sometimes called a virtual or logical location. From the customer’s point of view, there is one location; in reality, analysts are located in multiple physical locations.



The time when a CI or IT service is not available during its agreed-upon service time. The availability of an IT service is often calculated from downtime. 


Dynamic Answer

An ACD feature that automatically reconfigures the number of rings before the system answers calls, based on real-time queue information. Since costs don’t begin until the ACD answers calls, this feature can save callers or the call center money when long-distance 


A measure of whether the right amount of resources have been used to deliver a process, service or activity. An effective process achieves its objectives with the appropriate amount of time, money, people, or other resources. Often used together with Efficiency. 


A measure of whether the right amount of resources have been used to deliver a process, service, or activity and achieve its agreed-upon objectives. An efficient process achieves its objectives with the minimum amount of time, money, people, or other resources. Often used together with Effectiveness.


Electronic Display Board

An LED or LCD display, usually placed strategically in the customer support area as well as customer areas, used to notify personnel of problems or the current status of systems. See Reader Board.


Electronic Software Distribution

The capability of remotely uploading software programs or upgrades to customers’ workstations. This technology saves service desk or support center staff members from leaving their stations and making trips to the field. See Automatic Software Distribution.



The third level of the four-tier STEM hierarchy of classifying solutions in the case management system. The element category is used to offer additional information on the subject and type . On this level, specific versions of software and models of hardware will defined.


Also written e-mail. A common method of carrying messages over networks and/or the Internet.


An entire company or agency, possibly spanning many support centers.



All locations, departments, workgroups, and people within the company or organization. An enterprise-wide outage would affect everyone in the company.


Envelope Strategy

A strategy whereby enough analysts are scheduled for the day or week to handle both the inbound call load and other types of work. Priorities are based on the inbound call load. When the call load is heavy, all analysts handle calls, but when it is light, some analysts can be reassigned to “stuffing envelopes” or other collateral activities.



(1) The physical area where the service desk or support center is located. This includes the physical arrangements of personnel and workstations, lighting, noise, and room temperature. (2) The particular combination of software and/or hardware being used (e.g., the Windows environment).



Applying the most efficient arrangement of a desk, chair, monitor, telephone, headset, and other equipment to reduce or eliminate physical strain and cumulative trauma.


A unit of measurement: One hour of telephone traffic in an hour of time. For example, if circuits carry 120 minutes of traffic in an hour, that is two Erlangs.


Erlang B

A formula developed by A.K. Erlang , widely used to determine the number of trunks required to handle a known call load during a one-hour period. The formula assumes that if callers get busy signals, they go away forever, never to retry (lost calls cleared). Since some callers retry, Erlang B can underestimate trunks required. However, Erlang B is generally accurate in situations with few busy signals.


Erlang C

Named for A.K. Erlang , a method of calculating predicated waiting times (delay) based on three things: the number of analysts ; the number of people waiting to be served (callers), and the average amount of time it takes to serve each person. It can also predict the resources required to keep waiting times within targeted limits. Erlang C assumes no lost calls or busy signals, so it has a tendency to overestimate staff required.


Erlang, A.K.

A Danish engineer who worked for the Copenhagen Telephone Company in the early 1900s and developed Erlang B , Erlang C , and other telephone traffic engineering formulas.


A design flaw or malfunction that causes a failure of one or more CI's or IT services. A mistake made by a person or a faulty process that impacts a CI or IT service is also an error. 


Error Control

The processes involved in tracking known errors until they are eliminated by the successful implementation of a change. 



A defined management process by which a service request’s priority is changed due to the impact or timing of the request, customer input, or duration. Escalation is a management process for giving a call more priority, urgency, or resources. Also, movement of a case from a lower level of support to a higher one (from Level 1 to Level 2, for example--called hierarchical escalation) in order to assign the work to people with the appropriate skills, authority, and resources.

Event Survey

A survey conducted to evaluate your customers’ satisfaction with the resolution of a specific type of incident or any other ad hoc reason. See Incident-based Survey . Frequently called a transactional survey , because it deals with a particular transaction.

Exception Report

A document containing details of one or more KPI's or other important targets that have exceeded defined thresholds. Some examples include SLA targets that have been missed or are about to be missed and performance metrics that indicate a potential capacity problem.

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