ANSI/TIA-942-B & New Media Types

In an earlier blog, we discussed ANSI/TIA-942-B (the revision of the TIA-942-A data center standard), which had been balloted and was reviewed at the June TIA sub-committee meeting. The TIA sub-committee responsible for ANSI/TIA-942-B is in the process of resolving the hundreds of technical comments to the first draft of the B version of the document. The goal is to release the next draft for ballot and comment prior to the October TIA meetings.

As the ANSI/TIA-942-B standard is under development, it’s important to understand the new technology advances that impact it, as well as the difference between normative and informative guidance when it comes to using the ANSI/TIA-942-B document.

Two new media types have been approved by TIA as part of ANSI/TIA-942-B: Category 8 cabling and wideband multimode fiber. Here’s what we know so far about these two media types and what will be included in ANSI/TIA-942-B.

New Media Type No. 1:
Category 8 Cabling

The first of the two new media types covered by ANSI/TIA-942-B is Category 8 cabling, a balanced twisted-pair cabling system designed for higher-speed applications like 25GBASE-T and 40GBASE-T.

Cabling system performance is specified around a 2.0 GHz, 30m and 2-connector channel, with a maximum permanent link of 24m. I suspect that we will see applications for Category 8 cabling as “XoR” solutions – Top of Rack (ToR), Middle of Row (MoR) or End of Row (EoR) – where it could replace direct-attached cabling with direct-connected devices.

New Media Type No. 2:
Wideband Multimode Fiber

ANSI/TIA-942-B also covers wideband multimode fiber (WBMMF). It has been in development for a number of years, and the specifications have been published; however, the industry has not yet decided on an official name or OMx designator (OM5, for example); we’ll have to wait for IEC to come up with the official designator.

The reason it’s called “wideband multimode fiber” is due to the way the fiber is optimized for increased bandwidth by using multiple wavelengths in the lower end of the spectrum (850nm, 880nm, 910nm and 940nm).

This allows for VCSEL-based SWDM (short wavelength-division multiplexing), permitting a migration beyond 10 Gbps, 25 Gbps or 40 Gbps over a single duplex fiber optic channel using multimode fiber. SWDM4 has been demonstrated using a 100m channel to support 100 Gbps speeds. Experimental data has been shared with IEEE over longer channels; further study and development will occur over time, and the technology shows promise.

The SWDM Alliance continues to work on developing and promoting the use of SWDM to provide “cost-effective data center interconnections over duplex multimode fiber at rates at above 40 Gbps.” In theory, this could allow for 100G-SR, 400G-SR4 or even 1500G-SR16 and beyond. WBMMF will provide backward compatibility for legacy applications with OM4. Whether this will continue as proprietary applications or more widespread (and potentially standards-driven) usage will evolve in the coming months. Gone are the days when generational changes happened in five- to 10-year increments from an application space; instead, we are seeing an increasing pace and scope of change in the marketplace.

Questions About New Media Types?

If you have questions about ANSI/TIA-942-B, don’t hesitate to contact us. Because Belden chooses to be involved with standards development, we’re at the forefront of technology – and can help you be, too. Learn more about the experience and expertise we can bring to your data center to reduce costs, improve uptime, make the best use of space and ensure security.

Are you tracking updates about ANSI/TIA-942-B as they are released?
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