Looking for objective answers on what works. One leading company claims vectoring delivers almost no gain unless you vector everything in the node. A leading expert says that's hogwash, and most of the benefits can be achieved with a simpler and much less expensive retrofit. The DSL Forum has defined test methods that should provide some answers and Telebyte’s Michael Breneisen is now shipping early units with a 48 line emulator built in.
The unit fits in a standard rack. It’s been under development for two years in the high-tech zone of Hauppauge, Long Island, an hour outside New York City. Long Island remains something of a tech hub although the aviation and defense industry cut back years ago.
In 2004, a large roomful of engineers were amazed when the notion now called “vectoring” was first proposed and some were skeptical. In 2012, the doubts are gone but the practical how tos need answers. Until we have real world results, no one will be certain of the quality of the emulation or for that matter the practical limits of vectoring itself. Those answers are clearly very close, so much so that I’ve been recommending vectored gear for almost all new builds.
Tracespan released a vectored VDSL module for their VDSL Xpert analyzer a few days after I write the above. I've neither the facilities nor the expertise to evaluate the differences, so I'm arranging interviews with some experts who can clarify for me. Meantime, I'm including below the pr from both companies. If you have expertise you're willing to share, presumably far off the record, plese email me.
From the companies
Telebyte Announces the First Commercially Available Crosstalk Emulator for Vectored VDSL2 Testing
Telebyte’s Testing Solution Supports the Growth of Next-Generation High-Speed Internet Applications
Hauppauge, New York, USA — March 20th, 2012 — Today Telebyte, a US-based global xDSL test equipment solution provider, announced the release of the Model VxT-48 xTalk Emulator for Vectored VDSL2 Testing. The groundbreaking, 48-channel crosstalk emulator is now available worldwide, and answers the
growing need for repeatable, configurable performance testing of DSL equipment that utilizes Vectoring technology.
VDSL2 Vectoring dramatically increases data rates on copper telephone lines through cancellation of crosstalk between loops within and across cable binders. As the growth of DSL continues to overtake both fiber and cable combined, implementation of Vectoring on existing copper infrastructure is certain to interest DSL service providers who must keep pace with increased consumer demand for next-generation entertainment and business applications. The VxT-48 will help to accelerate that implementation, giving service providers a faster return on investment and helping them avoid the delay and high capital expenditures that come with investing in Fiber to the Home (FTTH). A reliable testing platform will also fast track universal broadband projects now mandated in many countries.
“With VDSL port shipments expected to continue their growth during the next five years, driven by new deployments, replacement of ADSL ports, vectoring, and pair bonding, operators require a way to quickly test their VDSL connections to ensure they are performing as advertised,” said Jeff Heynen, Directing Analyst, Broadband Access and Video at Infonetics. “Telebyte’s technology gives operators that physical layer testing capability required to speed up their vectored VDSL rollouts.”
Until today there has been no commercial solution for physical layer testing of Vectored VDSL2 equipment. The only choices have been Cable Farms where correlation of test results from site to site can be problematic.
The VxT-48 offers a reliable and automated way to measure the effect of vectoring on 48 line pairs, allowing service providers to compare and correlate test results with equipment vendors and from one location to another. This makes it ideal for performance testing.
“As soon as we saw that Vectoring would be a game changer for the industry we began working on a way to answer the testing challenge,” said Michael Breneisen, President of Telebyte. “As a leader in broadband test equipment, this was a natural evolution for Telebyte. We are the only company offering a commercially available Vectored VDSL2 test solution.”
The VXT-48 emulates the symmetric model of the ATIS Multiple-Input Multiple-Output (NIPP-NAI-2009-014R3) on 48 channels (using the upper-left 48 x 48 quadrant of the 100 x 100 random-drawn matrix). It also models crosstalk between xDSL multi-pairs within a cable binder and is sufficient for automatically running test cases for systems with vectoring capabilities. Remote commands or the VxT Control Center software may be used to control line lengths and micro-interruption settings.
Telebyte offers an outstanding line of products for local loop simulation, crosstalk emulation, noise generation, automated switching and Ring Trip simulation. The high-tech company’s solutions are used for physical-layer testing of xDSL technologies such as G.SHDSL, ADSL, ADSL2, ADSL2+, and VDSL2. In business since 1983, Telebyte (headquartered in Hauppauge, NY USA) sells its products to major companies around the world.
More information is available at www.telebytebroadband.com.
TraceSpan's VDSL Xpert™ Analyzer Supports G.Vector
Industry’s only real-time passive VDSL multi-layer analyzer can now analyze and troubleshoot VDSL2 lines with Self-FEXT Cancellation
TraceSpan Communications, a leader in broadband analysis and monitoring solutions, announced today the release of Self-FEXT Cancellation (G.Vector) module for its VDSL Xpert™ analyzer.
Self-FEXT Cancellation, also known as G.Vector, is standardized in the ITU-T G.993.5 recommendation, and allows significant rate improvements of VDSL lines by cancellation of far-end crosstalk (FEXT) among signals from pairs in a bundle.
The VDSL Xpert™ multi-layer analyzer provides a complete and accurate analysis of VDSL2 product performance and interoperability with no affect of the data transfer between the transceivers. Now, with its new G.Vector capability, VDSL Xpert™ allows its users to validate the performance improvement achieved by G.Vector, verify G.993.5 compliance of their VDSL2 equipment and chipsets, find and analyze problems related to G.Vector prior to their field deployment, and troubleshoot such problems on live networks in the field.
The latest VDSL Xpert™ version also adds new capabilities for troubleshooting issues related to multi-pair bonding, which is another key factor in extending service rate and reach over copper lines.
"Extending data rates on the copper infrastructure is a key success factor for today's telecom operators, and G.Vector is one of the means to achieve this", said Dr. Hanan Herzberg, TraceSpan founder and CEO. "VDSL Xpert™ can now help our customers maximize the performance of their copper lines by troubleshooting G.Vector-related problems quickly and easily, thus assuring service reliability and customer satisfaction".
With its unique multi-layer probing capability, VDSL Xpert™ provides comprehensive analysis with various outputs - from analog samples to bits and messages. In addition, it extracts the upper layers cells and packets and provides data, signaling and warnings of incompatibility with the various protocols. The supported protocols range from PTM, through network layer protocols such as IP and IGMP, and up to application layer protocols such as HTTP. VDSL Xpert™ simultaneously presents downstream and upstream data and the connection between the two. Its feature-rich GUI presents multi-layer information in convenient displays, and also allows automatic generation of exportable reports.