Network Infrastructure Blog

Q: Will we see a standard for 40 Gigabit Ethernet over twisted-pair  copper cabling and does the fact that ISO/IEC and the TIA are  investigating the requirements for achieving this increase the  possibility of it happening?

A: Yes and yes!  There are very strong indicators that development of a greater than 10Gbps Ethernet application for balanced twisted-pair cabling will begin in 2012.  These include:

1)  the availability of  IEEE 802.3ba compliant 40Gbps Ethernet computer backplanes,

2)  the availability of  IEEE 802.3ba compliant 40Gbps and 100Gbps Ethernet multimode and singlemode optical fiber network gear, and

3)  new work projects initiated by ISO/IEC and TIA to develop specifications for 100Ω Next Generation balanced twisted-pair cabling.

While it is likely that the IEEE 802.3 Ethernet Working Group will engineer this new twisted-pair Ethernet specification, there are no formally adopted objectives or specifications for a greater than 10Gbps Ethernet application at this time.  However, the indicators above provide significant clues regarding the characteristics of a greater than 10Gbps application and the cabling that will support it.

Because Ethernet applications for the LAN backbone and data center core have always preceded Ethernet specifications for the LAN horizontal and data center edge, it is a good bet that the next Ethernet over balanced twisted-pair speed will be 40Gbps.   At this time, the biggest driver demonstrating the great industry commitment to, interest in, and investment in the future of copper-based Ethernet is the work that is being done by ISO/IEC and TIA to develop Next Generation Cabling specifications.

ISO/IEC recently initiated a project to develop a new Standard tentatively entitled, “ISO/IEC 11801-99-x Guidance for balanced cabling in support of at least 40 GBit/s data transmission”.   This proposed 2 part Standard will address capabilities of both existing ISO/IEC 11801 compliant channels and channels with extended and/or enhanced performance characteristics.   TIA is currently working on a project to develop “Specifications for 100Ω Next Generation Cabling”, which is anticipated to be published as addendum 1 to ANSI/TIA-568-C.2.  From the efforts of these two groups, we can already surmise that next generation cabling supporting 40Gbps transmission will require at least 1GHz of bandwidth, be backwards compatible with existing Ethernet applications, and potentially drive the need for a new reduced length (i.e. less than 100 meter) topology specifically supporting data center deployments.

A New Work Item Proposal (NWIP) to develop requirements for balanced twisted-pair cabling capable of supporting 40 GBit/s data transmission  was initiated by ISO/IEC JTC 1/SC 25/WG 3 in October, 2011 at the Working Group’s  Melbourne, Australia meeting.  This proposal affirms the international cabling Standards community’s vision of supporting greater than 10 GBit/s Ethernet speeds with copper cabling.

The working title of this new project is expected to be, “ISO/IEC 11801-99-x Guidance for balanced cabling in support of at least 40 GBit/s data transmission” and the scope of work will address capabilities of both existing ISO/IEC 11801 compliant channels and channels with extended and/or enhanced performance characteristics.  These dual scopes will form Part 1 and Part 2 of the project as described below.

Part 1: Specification of the transmission characteristics of channels having at least two ISO/IEC 11801 compliant connections whose worst case length is the maximum practically achievable to support 40 Gbit/s data transmission.

Part 2: Specification of the transmission characteristics of channels consisting of connections exhibiting performance headroom to ISO/IEC 11801 requirements (e.g. higher bandwidth performance and/or improved transmission characteristics).  The transmission characteristics of these channels may be specified at or beyond their current bandwidth, with or without extended limit characterization, for 100 meter or shorter topologies, and with four or fewer connections.

Tutorials on expected channel capacity and anticipated electronics-related signal processing (e.g. noise cancellation) from ISO/IEC JTC 1/SC 25/WG 3 experts will help to define the capabilities of existing class E_A and F_A channels under a variety of performance and topology conditions, as well as identify opportunities for specification enhancement.

No objectives related to media, bandwidth, compatibility with TIA, or other characteristics have been defined at this time.  Brian Celella actively participates in the ISO/IEC JTC 1/SC 25/WG 3 Working Group and we will keep you advised when significant milestones are reached.

The TIA TR-42.7 Copper Cabling Subcommittee confirmed industry interest in a greater than 10 Gb/s copper-based Ethernet application when the following new cabling project was initiated in February, 2011:

Project Title: Specifications for 100Ω Next Generation Cabling

Scope: Develop a new category of cabling to support future applications beyond 10GBASE-T.

Justification: A new category of cabling to support increased capacity for future applications.

Next Generation Cabling performance parameters, which are anticipated to be published in addendum 1 to ANSI/TIA-568-C.2 in 2014, are being concurrently investigated by four task groups focused on the subjects of Application Space, Capacity, Cables, and Connectors. Siemon is committed to supporting both this project and next generation Ethernet applications. In fact, Brian Celella of Siemon is Chairing the Next Generation Connector task group and Valerie Maguire, also of Siemon and the author of this blog, is the Document Editor.

The scope of this exciting new project is converging and the TIA TR-42.7 Copper Cabling Subcommittee adopted the following baseline objectives for Next Generation Cabling in October, 2011:

While there is no formal IEEE 802.3 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 expects this application to continue to evolve with ever increasing data carrying capability well into the foreseeable future.

The TIA TR-42.7 Copper Cabling Subcommittee confirmed industry interest in a greater than 10 Gb/s copper-based Ethernet application when the following new cabling project was initiated in February, 2011:

Project Title: Specifications for 100Ω Next Generation Cabling

Scope: Develop a new category of cabling to support future applications beyond 10GBASE-T.

Justification: A new category of cabling to support increased capacity for future applications.

Next Generation Cabling performance parameters, which are anticipated to be published in addendum 1 to ANSI/TIA-568-C.2 in 2014, are being concurrently investigated by four task groups focused on the subjects of Application Space, Capacity, Cables, and Connectors. Siemon is committed to supporting both this project and next generation Ethernet applications. In fact, Brian Celella of Siemon is Chairing the Next Generation Connector task group and Valerie Maguire, also of Siemon and the author of this blog, is the Document Editor.

The scope of this exciting new project is converging and the TIA TR-42.7 Copper Cabling Subcommittee adopted the following baseline objectives for Next Generation Cabling in October, 2011:

While there is no formal IEEE 802.3 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 expects this application to continue to evolve with ever increasing data carrying capability well into the foreseeable future.

In a welcome nod to keeping things simple, the 2012 edition of IEEE Std 802.3 will feature a new and succinct title.  The unwieldy name of IEEE Std 802.3-2008 is:

IEEE Standard for Information technology –Telecommunications and information exchange between systems – Local and metropolitan area networks – Specific requirements Part 3: Carrier sense multiple access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications

The title of the 2012 edition is expected to be:

Standard for Ethernet

Kind of makes one wonder how we ended up with such an awkward title in the first place?!  Kudos to the IEEE 802.3 Ethernet Working Group for making our lives a little easier.

The IEEE 802.3 Maintenance Task Force is developing the 2012 edition of IEEE Std 802.3, which will incorporate approved maintenance changes and the content of the following standards:

IEEE Std 802.3at-2009 (DTE Power Enhancements),
IEEE Std 802.3av-2009 (10Gb/s PHY for EPON),
IEEE Std 802.3az-2010 (Energy-efficient Ethernet),
IEEE Std 802.3ba-2010 (40Gb/s and 100Gb/s Ethernet),
IEEE Std 802.3bc-2009 (Ethernet Organizationally Specific type, length, values  (TLVs)),
IEEE Std 802.3bf-2011 (Ethernet Support for the IEEE P802.1AS Time Synchronization Protocol),
IEEE Std 802.3bg-2011 (40Gb/s Ethernet Single-mode Fibre PMD), and
IEEE Std 802.3-2008/Cor1-2009 (Pause Reaction Delay Corrigendum)

Refer to the IEEE 802.3 Maintenance Public Area for further information.