Introduction
Cabling vendors require you to certify the cabling system if you desire a warranty. They do not permit you to use CableIQ or Validator. This suggests that neither CableIQ nor Validator are certifiers.
For warranted cabling systems, they require you to use an approved tester such as a DTX CableAnalyzer to certify their cabling system. They are underwriting the cabling system performance for up to xx years and their unwillingness to compromise on cable certification is understandable, because the potential financial loss to them and the end-user can be catastrophic.
Cabling Vendor Approvals
- CableIQ = none
- Validator = none
- DTX CableAnalyzer =
Who are these testers for?
They are most certainly not a cheap certifier and should not be advertised/sold as such. If you are installing a new cabling system, the warranty given by the cabling manufacturer will require full certification using a Level IIe, III, IIIe or IV tester depending on the category of the cabling system. CableIQ and Validator are neither of these. If you have an existing installation of an unknown quality, then testers such as CableIQ become an acceptable alternative to a full blown certification test. In such cases, you simply want to know whether the application will either work or not on the link. However, the tester must still perform all of the tests dictated by the application standard(s). Of note, there is no mention of ELFEXT, a requirement of 1000BASE-T in the Validator literature.
A brief technical overview:
IEEE802.3:2002
Looking at this application standard for 1000BASE-T Ethernet, we find:
“40.7.2 Link transmission parameters
The transmission parameters contained in this subclause are specified to ensure that a Category 5 link segment of up to at least 100 m will provide a reliable medium. The transmission parameters of the link segment include insertion loss, delay parameters, characteristic impedance, NEXT loss, ELFEXT loss, and return loss.”
Bit error rate (Bert) testing is not required. The IEEE believes testing the parameters in clause 40.7.2 will result in a Bert of better than or equal to 10-10.
With these technical points in mind, now ask for a demonstration of the product. The CableIQ is smaller, lighter and contains diagnostic tools that provide the location of failures in a cabling system for Return Loss AND NEXT. And, the tests are carried out in 6 seconds.
Before you read this, I am surprised that any vendor should issue such a negative and technically incorrect document. The wording in plum is the text from a document issued by Test-Um called “The Science of ValidatorTM”. Please ask us any questions or concerns you have using Provide us with feedback on this article.
“The main question we are asked about Validator is whether it is “really” a Certifier. This can be answered with a resounding YES. Validator is a Certifier. It certifies cable runs against TIA568 Interconnect Standards and with TIA568 noise and delay measurements.” – The current cabling standard from ANSI is TIA/EIA-568-B.
There are many aspects of ANSI/TIA/EIA-568-B that Validator does not meet, including:
1. Does not eliminate the connection to the tester (TIA/EIA-568-B.1 Clause 11.2.3)
2. Fails to report worst case margin and worst case values (TIA/EIA-568-B.2 Annex I)
3. Does not meet the minimum frequency step requirements (TIA/EIA-568-B.2 Tables I.4 & I.5)
4. Does not measure ELFEXT, PSELFEXT (TIA/EIA-568-B.1 Clause 11.2.4.1)
5. Does not distinguish between Permanent Link & Channel testing (TIA/EIA-568-B.1 Clause 11.2.3)
6. Does not take into account the 10% uncertainty of NVP (TIA/EIA-568-B.1 Clause 11.2.4.3.1)
7. No marginal pass/fail warning (TIA/EIA-568-B.2 Annex I.2.2)
8. Not Level IIe accurate (TIA/EIA-568-B.2 Tables I.4 & I.5)
9. Not Level III accurate (TIA/EIA-568-B.2-1 Annex B.1)
10. Does not apply 3 dB rule to Return Loss measurements (TIA/EIA-568-B.2-3 Clause I.2.5)
These same requirements can be found in the International Standards ISO/IEC 11801:2002, IEC61935-1 and the European Standard EN50173:2002. These requirements are global and not limited to North America.
You can purchase a copy of ANSI/TIA/EIA-568-B Series online at http://www.tiaonline.org/standards/search_results2.cfm?document_no=568-B
“The Validator uses digital signal generation to measure the actual noise levels on a cable run, Signal-to-Noise ratio (SNR) and adds the BERT test as a demonstration of error free transmissions of actual digital data over that line. “ – There is no such thing as error free transmissions. There is a minimum requirement of better than or equal to 10-10 found in IEEE802.3 Clause 40.1.1 paragraph g).
“In effect, our BERT test is an advanced version of the PSFENEXT measurement mentioned in TIA568.” – There is no such term as PSFENEXT in link testing, either in IEEE or TIA. There is PSELFEXT, Power Sum Equal Level Far-End Crosstalk. Far-End Crosstalk on its own is meaningless unless you take into account the insertion loss of the link; hence PSELFEXT. PSELFEXT is one of the parameters missing in the original Category 5, which is why the IEEE asked the TIA to propose limit lines for it. They did in the form of TIA/EIA-TSB-95 which was incorporated into the IEEE 802.3ab standard for 1000BASE-T.
“Despite the legitimacy of the Validator science in certifying a cable’s capability, the fact is that TIA568 is taken as the only “standard” by much of the BICSI cabling industry. The logic here is that there is no competing “spec” to refer to. However, the truth is that IEEE802.3 defines a speed specification and an error rate that has to be matched for an Ethernet system to be able to transfer data at given speeds. That is why we refer to IEEE802.3. It discusses actual Ethernet needs, not cable potentials as TIA568/570 do.” – Clause 40.7.2 detailed above from IEEE802.3:2002 appears to contradicts this statement. You can download a free copy by clicking here. There’s also the International and European Standards mentioned previously,
“The traditional certifier manufacturers know that questions are raised about the “natural” limits of the Ethernet speed standard and constantly search for and promote “future proofing.” To do this they have to come up with new performance levels.” – Tester manufacturers react to market requirements; they do not promote new performance levels. The IEEE committees are directly linked to the TIA and ISO bodies. For 10GBASE-T, it is the IEEE doing the pushing and the TIA is reacting by providing cabling data. When developing 1000BASE-T in 1997, the IEEE looked to the TIA for cabling performance parameters. TIA/EIA issued TIA/EIA-TSB95 which, as mentioned previously, was incorporated into IEEE 802.3ab 1000BASE-T.
“The truth is, as most network scientists know, 10 Gigabit will not be able to get out of the labs and data centers for the foreseeable future, since there are no applications where it is necessary, nor copper cable or components available to carry 10Gigabits more than 10 meters.” – 10GBASE-T has an objective to run up to 55 meters on existing category 6 UTP installations and 100 meters on category 6 FTP installations (Draft IEEE802.3an). http://www.ieee802.org/3/an/
“How many of us are worried about the “accuracy” of our cell phones or have to send them in once a year for “calibration” like what has to be done on a traditional certifier?” – This statement is the most cause of concern coming from a test equipment manufacturer. ALL test equipment has a period of calibration. Their characteristics change over time. This statement would suggest that the Validator cannot be calibrated. If you are an ISO9000 company, this may be an issue as all equipment must hold a valid calibration. Fluke has a long tradition of calibration practices. It has “the volt” here in Seattle.
“Fear of not meeting cable manufacturers guarantee schemes, fear of some liability due to a cable that does not work as the network owner desires, fear of not being able to “guarantee” a job’s worth. We reject this shabby and purposely deceptive method of marketing. Validator is not here to make its customers afraid. “
There really is no response to this. The cable tester market was driven by customers in 1994 who realized that they needed a full test to be assured 100BASE-TX would run on the cabling system they had or were going to install. Nothing has changed except the move to IEEE 802.3ab and the soon to be IEEE 802.3an.
Let’s keep this on a technical level please. Fluke Networks is an active participant of TIA, ISO, EN, IEC and IEEE bodies. Our representative is Henriecus Koeman. You can find his work across all of these bodies. His current contribution to IEEE is in the form of Alien Crosstalk Measurements. This same contribution can be found in TIA and at ISO level. Our goal is simple. Make the limits realistic and provide an accurate test solution.
*Validator is a trademark of Test-Um Inc.
Learn About:
- Troubleshooting LANs
- 10 Gigabit
- Cable Installation
- Fiber Testing