Updated April 7, 2014 with information on the re-issue of ANSI/TIA-942-A
The Telecommunications Industry Association (TIA) and The Uptime Institute recently issued a joint statement announcing that “going forward, TIA will revise the ANSI/TIA-942 … TIA-942-A Standard to remove the word ‘Tier.’” The two organizations described this agreement between them as a “step to bring success to the future of the data and communications industry by establishing clear and concise lexicon for the design of data centers as they are planned, constructed and operated worldwide. Both the Uptime Institute and TIA believe that it is in the best interests of the industry to permanently differentiate their respective data center infrastructure benchmarking systems.”
Coinciding with this statement, the TIA re-issued the ANSI/TIA-942-A standard with the editorial change that removed the word "Tier" from the annex that discusses cabling-system redundancy. The re-issued standard has a more-recent date than the original 942-A, but the re-issue does not affect the standard's five-year revision-cycle schedule.
The TIA emphasized that the change made to the standard was editorial, not substantive, in nature. In fact, the original standard did not mention The Uptime Institute, nor does the editorially revised version. The cabling schematics and practices prescribed in the original 942-A remain what they were, and under the newly re-issued ANSI/TIA-942-A, achieving a certain level of redundancy requires exactly what it required under the original. The only difference is the elimination of the word "Tier."
Uptime Institute chief operating officer Julian Kudritzki commented, “We appreciate the willingness of TIA and the TR-42 Engineering Committee to work together on this matter. Clear ownership of a benchmarking system is key to its utility, consistency and accountability. By disentangling our respective terminologies, both TIA and Uptime Institute are better able to pursue the independent development of standards and programs as each sees fit. We are confident that this is the lasting and public solution for the issue.”
TIA’s president, Grant Seiffert, added, “TIA and the Uptime Institute share the vision of greater efficiency to data center designs. TIA’s TR-42 Engineering Committee will continue to establish and improve voluntary consensus-based standards that enable the data centers which our consumers and businesses demand. Working with the Uptime Institute on this and other issues demonstrates the best aspects of what TIA can do to help the communications industry meet tomorrow’s challenges.”
In the 1990s, the Uptime Institute established the Tier Classification System “as a means to effectively evaluate data center infrastructure as it relates to business requirements for system availability,” the organization said. The TIA’s TIA-942 and TIA-942-A standards used the term “Tier” to describe levels of reliability, where Tier 1 has no redundancy and Tier 4 provides the highest degree of fault tolerance. The architecture, security, structural, electrical, grounding, mechanical, and fire protection guidelines are organized into four tiers. (Source: “TIA data center standard nearing completion,” August 2004)
At times the Uptime Institute was vocal about its apparent disapproval of the term appearing in TIA’s 942 standards. In 2010 the organization dedicated an installment of its “Tier Myths and Misconceptions” series to the issue. “The similarities between the Uptime Institute Tiers and TIA-942 stop at the surface,” the Institute said. “Uptime Institute’s Tiers is functionally disconnected from TIA-942.”
The recent agreement between the two organizations brings that discussion to a close.