Data Center Glossary

Clearly, choosing where to house your critical information systems is among the most important business decisions you’ll make, so we know you want to be sure you’re completely informed.

Browse our list of data center terms and technical jargon to clarify any confusion. Of course, definitions never tell the whole story, so for a more in-depth explanation of these terms or how our services and infrastructure can protect your business’ most sensitive assets, simply contact us to speak with one of our colocation specialists.


  • 2N Redundancy

    A measure of redundancy where additional “spare” components are available in the event that there is a system failure on one of the main critical components. N is the “Needed” components and 2 represents the existence of twice the “Needed” component that is on hand for emergency use.

  • Air Handlers (CRAH)

    Computer Room Air Handlers--the air system that provides precise temperature and humidity control for data center design, ensuring the optimal indoor environment.

  • Biometric Access

    A technique used in computer and facility security to authenticate an operator using physical characteristics, i.e., facial recognition, fingerprint scans, retinal scans, iris recognition and hand geometry.

  • Blade Server

    A computer optimized to use minimal physical space and power without compromising functionality. A standard data center rack can hold 42 1-U servers vs. 128 blade servers.

  • Carrier Neutral

    A data center facility that permits clients to contract with any telecommunication provider they choose.

  • Colocation

    The practice of locating critical technology assets, like computers, routers and data storage systems, in an off-site data center which specializes in managing the critical power and cooling infrastructure required to support computer operations.

  • Concurrently Maintainable

    A design standard that provides a data center the ability to perform planned and unplanned emergency maintenance without disrupting the computer hardware operation.

  • HVAC

    Heating, Ventilating and Air Conditioning--the central air conditioning system used to regulate temperature and humidity indoors while optimizing conditions and efficiency.

  • Metered Power

    A way of measuring power consumption that ensures the customer only pays for the amount of power used over a designated period of time.

  • N+1 Redundancy

    A measure of redundancy where additional “spare” components are available in the event of a failure in one of the main critical components. N is the “Needed” components and +1 represents the spare component that is on hand for emergency use. N+1 safeguards against lost productivity if one component fails.

  • Network Cross Connects

    A physical network connection bridging a telecommunications vendor with a customer’s computer environment inside a data center.

  • Power Distribution Units (PDU)

    A device used to distribute high voltage electric power by reducing it to more common and useful levels (220 and 120 volt power) that computer room hardware can utilize.

  • Redundancy

    The duplication of critical infrastructure support systems with the intention of backing up the primary systems and protecting against system down-time due to failure.

  • Scalability

    The ability for the required infrastructure to be enlarged or handle increased capacity input without efficiency or reliability being compromised.

  • SSAE-16 Type II Audit

    SSAE-16 is a thorough audit report on the operational processes of a service organization where professional standards are set up for a service auditor that audits and assesses the internal controls of a service organization. Type II reports are more thorough than a Type I Report, because the auditors give an opinion on the effectiveness of the controls operated under a specific time period of the review. The Type I report only lists the controls, while Type II tests the efficiency of these controls to reasonably assure that they are working correctly.

  • Tier III

    A data center construction classification where the critical facility infrastructure supporting the IT systems is composed of multiple active power and cooling distribution paths, has multiple redundant infrastructure components, and is concurrently maintainable--meaning there is never any scheduled downtime.

  • UPS Power

    Uninterrupted Power Supply--A critical data center component that cleans incoming “dirty” power from the commercial utility power and provides instantaneous back-up power when a main power source fails.

  • Virtualization

    A new approach to information/database management where data from multiple sources is aggregated to create a single, virtual view of information to be applied in business processes.