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The Category 6A copper cable specification (TIA 568-B.2-10) has been issued. Have you installed the new standard yet? Do you know why a customer would want it? I asked some manufacturers what concerns they were hearing from customers and why their product might fit the bill.
REPLIES FROM CABLE MANUFACTURERS:
Are customers calling to find out more about your Category 6A product?
Yes. People are more comfortable when there is an existing standard to measure the product against. If a company is planning to upgrade to 10 gigabit Ethernet, they want the right cable and want it verified by Underwriters Laboratories or ETL-SEMKO, but the price is still hard to handle.
Do customers ask if your product meets a Telecommunications Industry Association (TIA) standard?
Some do and some don’t. The ones who ask need to know which labs do all the tests in the TIA standard. Other customers ask if it meets the IEEE 10 gigabit Ethernet standard or if it can handle 10 gigabit Ethernet. We, the manufacturer, must let them know that it meets TIA 568-B.2-10, that it has been “verified” by an independent testing lab and that it can handle 10 gigabit Ethernet transmission. All in all, customers do care if the product meets the standard they are interested in.
Are customers concerned with being able to go 100 meters in distance?
That’s a big component of the sale, and customers are very concerned, especially if they have just installed Cat 6 cabling (TIA TSB 155 says Cat 6 cabling can operate 10 gigabits over 37–55 meters). An example where 100 meters is needed would be a high-rise hotel that wants the long distance. With 6A, the cabling can go up more floors without the need for more telecom closets.
Is the larger outside diameter (OD) of a Cat 6A cable problematic?
The larger diameter certainly is a factor. The larger OD Category 6A cable can take up more space in a smaller conduit, but there’s more of a difference when a wide cable tray is used. A smaller OD Cat 6A could mean almost 100 extra cables could fit, saving the customer money. Then, there’s Cat 6A shielded that has a smaller diameter, too; it has no alien crosstalk (AXT, an electromagnetic noise that can show up in a cable that runs alongside one or more other signal-carrying cables, usually occurring between different cables in a group or bundle); it’s immune to RFI; and it goes 100 meters because it passes TIA 568-B.2-10. At this point, even though this is a significant feature, it’s not something anyone is willing to pay more for.
Are customers mainly using Cat 6A in the data center?
Strangely enough, we are not finding that customers are seeking an end-to-end solution; they just want a solution that works and for the cable to have significant margins for all AXT parameters. Some consider Cat 6A for where the cable pathway runs from panel to panel in the data center, but there are a number of projects to the desktop, too. The financial market, in particular, tends to want a shielded cable.
Is installing Cat 6A in a new building a given?
When installing cabling in a new building, the customer should want 10 gigabit. Nothing else makes sense. Considering the expense for the cable, that only makes up 3–5 percent (from Cat 5e to 6A for 10 gigabit). So, for 1 or 2 percent of the total network expense, why wouldn’t you put something in that will give you a cabling infrastructure that will last 10 to 15 years or more? All in all, there always are budget constraints, and again, this choice has a lot to do with a company’s goals.
How does a customer make a decision when installing cabling in an existing building?
Some institutions are putting in cable for the future that could be a step up from what they have now, or it could be Cat 6A. It was suggested that the client do a needs assessment:
A. Do they own or rent their space?
B. Is this a retrofit for long-term, or is it short-term?
C. How long are they staying in that building?
D. What are their user’s current networking needs?
E. What do they anticipate their networking needs to migrate to in one, five or 10 years?
Why is shielded Cat 6 an option for 10 gigabit Ethernet?
It is recommended where there is a lot of ambient electromagnetic interference (EMI) or radio frequency interference (RFI) noise. In general, shielded cable does not guarantee AXT performance. If they are not terminated properly, the shield acts as an antenna that attracts signals instead of isolating them. Also, the foil can crack from flexing. That is why an unshielded-twisted pair (UTP) cable has a minimum bend radius of four times the cable diameter, and a foiled UTP (F/UTP) cable has a bend radius of eight times the cable diameter (per TIA 568-B). Also, the shielded cable should meet TIA 568-B.2, Addendum 10, component specs, so it can be verified and sweep tested to 500 MHz. Remember, Cat 6 cable doesn’t have any AXT requirements specified in great detail in TIA 568-B.2, Addendum 10, but Cat 6A does.
What is your advice to a potential customer?
Do a needs assessment to be comfortable with your decision, and remember that, just as in the real estate industry where they tell you to “buy as much house as you can,” in the cable industry, the saying is “buy as much cable plant as you can” because you will own it. Put in the most advanced cable now, and upgrade the electronics later.
REPLIES FROM A PATHWAYS MANUFACTURER:
What is the biggest concern you are hearing about installing Category 6A cabling in your pathways?
Customers want to know how to handle the “cable fill” requirement. They need to plan accordingly. Cabling lasts 10–12 years, but the pathway could last three times that. You need to consider growth.
How does your pathway adapt to a Cat 6A type cable?
The product/pathway itself has a fixed size on the outside, but the partitions inside can be changed. When a pathway is first installed, there is usually more space given for communications cable. The designer estimates growth, and we match that.
Are customers asking about pathways for data centers?
We have a product that goes under the raised floor and in trays (basket/ladder) and then up into the server through a hole in the floor. When the cable leaves the data center, it goes into an enclosed pathway where data center heat is no longer an issue.
How is the bend radius of this thicker Cat 6A cable handled in a pathway?
If it is a straight run, there are no problems. We have a way to control the bend radius. And, with 10 gigabit Ethernet applications, the entire channel has to be correct. The photo on the right shows how the bend radius can be controlled.
Are there any other concerns when installing this Cat 6A cable in a pathway?
The most important place is where the cables go into the jack. Bend radius, again, is very important here. You can see from the photo on the left that the cable bend is lessened because it’s a “gentle bend” coming into the back of the jack. This is where it is most sensitive. The bend control is already in the pathway design, and this is where most installers have problems.
What is your advice to the customer?
Have the pathway properly sized and working for the entire channel, from the equipment room through the raceway, regarding “bend radius” and “fill.” Get specific information from the cable manufacturer about 10 gigabit Ethernet and Cat 6A cabling before putting it in a pathway. Remember that termination and the size of the cable are very important. Be sure you have the right cable for the job. And remember that, when pathways are installed around the walls inside a building, there are inserts that are removable and adjustable to control bends.
IN CONCLUSION:
Customers should know what their needs are. You can help your clients by speaking about cabling and pathway concerns upfront. Discuss the bend radius, how to terminate, the size of the outside diameter and using 10 gigabit Ethernet.
Technical information and illustrations provided by Mohawk, Hitachi Cable Manchester and Wiremold.
MICHELSON, president of Jackson, Calif.-based Business Communication Services and publisher of the BCS Reports, is an expert in TIA/EIA performance standards. Contact her at www.bcsreports.com or [email protected].