By Patrick McLaughlin
In late 2015 the Telecommunications Industry Association (TIA) issued a call for interest for the standard titled TIA-942-B, which will be the second (“B”) revision to the Telecommunications Infrastructure Standard for Data Centers. As an ANSI-accredited standard-development organization, TIA revises its standards on a five-year cycle. The TIA-942-A standard was published in 2012.
In its call for interest, the TIA explained that the 942 set of standards “specifies the minimum requirements for telecommunications infrastructure of data centers and computer rooms, including single-tenant enterprise data centers and multi-tenant Internet hosting data centers. The topology specified in standards is intended to be scalable to any size data center.”
The association further explained that this standard “serves as a critical tool to evaluate existing data centers and communicate design requirements for new data centers. These include cabling, facility and network design elements.”
At its January 2016 meeting, TR-42.1 agreed to issue the current draft of TIA-942-B for committee ballot. That ballot was completed in April. A substantial element in the balloting process is resolving comments made by committee members. The committee ballot that wrapped up in April produced more than 100 pages of comments, which will be resolved when TR-42.1 meets again June 15 and 16.
The first draft of TIA-942-B that went through committee balloting includes the following changes from the TIA-942-A standard.
1) It incorporates Addendum 1 to the 942-A standard, which addressed data center fabrics, as a new Annex.
2) It adds 16- and 32-fiber MPO-style array connectors as an addition connector type for termination of more than two fibers. The 16- and 32-fiber connectors were recently standardized when ANSI/TIA-604-18 was published.
3) It adds Category 8 as an allowed type of balanced twisted-pair cable, and changes the recommendation for Category 6A balanced twisted-pair cable to Category 6A or higher.
There is some likelihood that wideband multimode fiber (WBMMF) will be included in 942-B as both an allowed and a recommended fiber type. The TIA-492-AAAE standard that will specify WBMMF is close to publication.
As the TR-42.1 Committee undertakes the revision process, they are considering the practicality that the TIA-942 standard series has been used globally. As a TIA standard, 942 and 942-A are developed under the processes prescribed by the American National Standards Institute (ANSI). Generally TIA cabling standards are applied in North America. But the 942 series has been widely adopted in other regions. As such, users of the document outside the United States could benefit if the “B” revision incorporates terms and references that are applicable outside the U.S.
For example, the current “A” version references documents published by the National Fire Protection Association and used in the U.S. Also, measurements that reference feet rather than meters appear to be U.S.-centric. And 120V, 20A electrical systems largely apply to U.S. facilities. Through the comment-resolution process, these and other “U.S./international” issues will be resolved.
Patrick McLaughlin is our chief editor.
