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In this Infographic, we look at key points in the timeline of 10Gb/s copper cabling and the 10GBASE-T application standard. From early cabling options to current and future developments, it shows 10GBASE-T and twisted-pair copper cabling’s projected rise to 10Gb/s Ethernet dominance.
To learn more about 10Gb/s copper cabling, check out the whitepaper “State of the Network: 10GBASE-T Equipment Availability and the Future of Copper Media“.
The purpose of this document is to communicate Siemon’s position in response to a recent paper from a competitor titled, “Suitability of Category 7A/Class FA As A “Future Proofing Media For 40 Gbps Applications,” dated April 2012. This document also conveys Siemon’s interpretation of standards activities relating to suitability of class FA cabling (comprised of category 7A components) for future networking applications having transmission rates above 10Gbps.
The TIA TR-42.7 Baseline Objectives for Next Generation Cabling identify the characteristic, “must exceed the TIA category 6A specification in at least 1 parameter” as “nice to have”. Furthermore, the IEC/PAS 61076-3-104 Standard, which describes the performance of the Siemon TERA™ interface, is being updated to support frequencies up to 2 GHz. Because class FA exceeds all category 6A specifications for every transmission parameter, class FA cabling is better positioned to support extended lengths, reduced latency, and reduced power consumption than any other copper media type, when a 40Gbps application is finally approved. In the absence of application objectives or an IEEE 802.3 40Gbps call-for-interest (CFI), no one, including Siemon, can make definitive claims about the ability of specific twisted-pair cabling implementations to reliably support transmission rates up to or beyond 40Gbps at this time. Our position on the inaccurate statements included in the competitor paper regarding class FA cabling is provided below:
| 1 | Misstatement: “[The TIA Category 7A PAR] was not accepted by TIA TR-42.7 as sufficient to meet the needs of 40GBASE-T” Fact: The TR-42.7 motion for this new project request failed to achieve greater than 2/3rd’s majority support by one vote (10 votes in favor and 5 votes opposed). While there was great interest in adopting class FA/category 7A requirements, there were several voting members who expressed the opinion that 40Gbps speeds could be realized by cabling with performance less stringent than class FA. |
| 2 | Misstatement: “Whether the crosstalk is mitigated via signal processing or cable sharing, from this perspective, Category 7A and Category 6A cabling in the absence of alien crosstalk are equivalent.” Fact: An Ethernet physical layer device (PHY) can detect less noise in a screened/shielded system during the training mode and back-off on the FEC (forward error correction) algorithm, which results in lower power consumption. Power savings is highly variable, but can be up to 10% with incremental savings based on channel length and noise immunity. For example, power back off savings potential is greater for category 6A F/UTP channels versus category 6A UTP channels, and is greater for category 7A S/FTP channels versus category 6A F/UTP channels. |
| 3 | Misstatement: “Adapter cords are not an acceptable solution since the customer will be forced to maintain two sets of equipment cords to ensure interoperability and portability between new and legacy installations.” Fact: Hybrid cords that adapt from one interface to another are commonly used in both twisted‑pair (e.g. block-based systems) and optical fiber (e.g. MPO/MTP to LC systems). These solutions are fully standards compliant and, in some cases, provide additional security. In no case is there a need for customers to maintain two sets of equipment cords. |
| 4 | Misstatement: “The majority of category 7A installations are installed as a hybrid system using category 7A cable with category 6A shielded RJ45 connectors and cords. This essentially makes the installed cabling system a category 6A solution.” Fact: Only category 7A connectors are deployed in Siemon class FA cabling systems. The RJ‑45 modular plugs at both ends of the channel are considered equipment connections and are outside of the scope of both the TIA and ISO/IEC channel definitions as shown in the figure excerpted from ANSI/TIA-568-C.2 below. Irrespective of the equipment interface, class FA compliant cabling channels comprised of category 7A |
| 5 | Misstatement: “At present, category 7A is a cabling specification that is not called out by any LAN or SAN application Standard”. Fact: Class F cabling (comprised of category 7 components) is explicitly called out as a recognized media in the IEEE 802.3an 10GBASE-T Standard and the newer class FA specification is expected to be incorporated into the next edition IEEE 802.3-2012 Standard. Furthermore, ISO/IEC has initiated a new Work Item Proposal tentatively titled, “ISO/IEC 11801‑99-x Guidance for balanced cabling in support of at least 40 GBit/s data transmission, Part 2” to develop guidelines addressing the 40 Gb/s capacity exhibited by existing classes of cabling, including class FA.While there is no formal IEEE 802.3 40Gbps project Call-For-Interest at this time, all early indicators show that there is great industry commitment to and investment in the future of copper-based Ethernet. Siemon actively participates in the TIA and ISO/IEC Cabling Standards committees that are developing modeling and performance specifications, in addition to the IEEE 802.3 Ethernet Working Group. We stand behind our mission to engineer the highest performing cabling solutions and provide fact-based product selection information to our customers. |
In summary:
It is OK to raise temperatures in the data center?
According to the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) and equipment manufacturers, it is.
New recommendations in ASHRAE 72-74 (22-23C) suggest it is no longer necessary to keep data centers at 68-69 degrees.
So, how does this relate to network cabling and data center cabinet selection?
Warmer overall temperatures in the data center can cause a chain reaction that gives shielded cabling and VersaPOD a competitive advantage.
The warmer the air that goes into the front of servers and switches, the warmer the air that comes out the back. In most cases, the cabling is in the rear of the server cabinets, and the patching is at the top right in the path of higher temperature airflow. (see image)
Cabling system performance can be adversely affected by heat and should be derated accordingly. Shielded systems are more temperature resistant than UTP, requiring as little as half the temperature derating of UTP. This means that shielded systems are better suited to higher temperature data center environments. Learn more about the advantages of shielded cabling in the Shielded Copper Cabling Resource Center.
With Siemon VersaPOD data center cabinets, cabling is routed in the Zero-U vertical spaces between bayed cabinets and out of the hot zone at the top of the cabinet, further protecting cabling from the potential effects of hotter data centers.
Cabling Installation and Maintenance Magazine has just published an interesting article on 10GBASE-T and twisted pair copper cabling in their March issue. Written by Ron Cates of PLX (a leading 10Gb/s PHY developer) and Siemon’s Val Maguire, it gives a solid overview of recent developments in 10GBASE-T equipment technology and the effect it will have on the future of twisted pair cabling.
CI&M Article: LINK
Key Point Overview:
Check out this cover article from Processor Magazine, written with input from Siemon. It gives an overview of the latest 10GBASE-T active equipment technology advancements and how they indicate a strong future for twisted pair copper cabling. Focusing on drastically reduced power consumption versus previous generations of 10GBASE-T PHYs, reduced deployment and maintenance costs and improved infrastructure flexibility, it is a brief and solid rundown on the current state of 10Gb/s ethernet and structured cabling.
