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cat5, vs cat5e, vs cat 6 explain difference 5

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phoneguy422

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Nov 23, 2002
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How do you explain to an end user the difference between the three? and when would you recomend an upgrade in cabling from cat 5e to cat 6?
 
This is as I understand it.

Cat 5 was the first UTP Standard to attempt to do 100 Mbps, there were some issues with Full Duplex crosstalk which are resolved in Cat 5e.

Cat 5e also supports 1 Gbps ethernet, but not faster.

Cat 6 was the first UTP Standard to attempt to do 10 Gbps, but is only rated to 37 m at 10 Gbps.

Cat 6A addresses this and supports 10 Gbps ethernet to 100 m.

I tried to remain child-like, all I acheived was childish.
 
Actually, CAT3 attempted to acheive 100mbps with a standard called 100BT4 - this did not get much acceptance however, and only a few OEM's created 100BT4 hubs and NICs. The attempt was 100mbps over all 4 pair.

100BTX was the first standard to allow up to 100mbps Ethernet over 2 pair.
 
HungryHouse provides a nice history lesson. There is such a fever-pitch over CAT6 that it makes me crazy. The types of speeds we are talking about have been addressed for many, many years.

The only time I would recommend an upgrade is if you have heavy local client/server activity (i.e., where a tremendous amount of data has to get from one local machine to another). I'm thinking of places like computer animation studios.

Most shops just want email and the ability to browse the web. Upgrading the cabling in a joint like that wastes your time and the client's money, because the uplink will always be the bottleneck. If there is heavy use, you may find that the installation of fiber optic (at typically about 80 cents a foot) is ultimately more cost effective that two or three cable upgrades in the coming years.

The link that hawks provides is also very good because of the "Do and Do Not" section at the bottom of the page. It emphasizes the importance of the installation techniques and practices, which is of most importance in meeting the Category level requirements.


[Rant BEGIN]

Way too many people have the idea that the term "Category" strictly defines cable. It doesn't. CAT5e for example is a standard that specifies the characteristics of the cable, terminating hardware and the process for installing said materials. Looped CAT5e cable or runs with 180 degree kinks = junk. CAT5e cable that's been skinned back five inches with two inches of untwist = junk too. And CAT (ANYTHING) cable is junk when it's run in parallel to high voltage for any significant lengths.

And be wary of the word "standard". It is bantied about far too often by marketers. CAT6 is no more a standard than CAT1 or CAT5.

[Rant END]
 
don't you just love the high price cat 6 patch cords at best buy an places like that ?

you know folks are buying them , expecting better performance on their 5mbps Internet connections that would work just fine with cat 3 [wink]
 
I can't agree more with last two posts. Dagwoodsystems gave an excellent post with tons of practicality and real life experience. skip- it is funny how we still hear that.
 
I know lots of couth goes into this …but the CAT6 cable has more twists per inch and is "better" manufactured than the CAT5e.
The "twist" effect of each pair in the cables will cause any interference presented/picked up on one cable to be cancelled out by the cable's partner which twists around the initial cable. The CAT6 cable “copper process” has been designed with fewer "impurities" that can pass signals better than impurities that reflect the signal.

Should they upgrade...Yes if they can afford it. Should I upgrade to Microsoft Vista from XP?

Regards
Peter Buitenhek
ProfitDeveloper.com
 
There IS a noise cancellation effect produced by pair twisting. However, the primary goal of this twisting is to eliminate crosstalk and capacitance between the pairs of the cable, NOT noise from external sources. I have heard claims that twisted pair eliminates RF tranmissions as well. However, if you've ever installed high-grade unshielded twisted pair anywhere near a radio station, you know that this is complete bull. That goes for 110/220 volt power cables as well. In a high noise environment, sheilded twisted pair (grounded on one end only) or fiber optic is the ticket.

In less harse environments where ordinary unshielded cable can be used, the performance difference between a CAT6 install and a CAT5e install may only be seen with a Fluke testor. In fact, I would be inclined to say that the difference between an OK install of CAT5e and a superior by-the-book install of CAT5e would reveal a more dramatic difference than the performance delta of CAT5e to CAT6.

Also note that THERE IS NO SPEED INCREASE with CAT6. Network speed is based on the network interface cards, switch/router interfaces and of course the cabling. If everything in your network is 100M (or even Gigabit) and you are using properly installed CAT5e, "upgrading" to CAT6 won't make a bit of difference.

There are very slight downsides to CAT6 as well. For example, the cable jacket is a lot heavier and tends to fill up conduit a lot faster. It's a slight pain to punch and a huge pain to skin. The cable doesn't bend as easily either, partially because the copper is a slightly heavier gauge. Why? Because as you increase the number of twists per inch, you also increase the length of the wire (think of a helix in space). Longer wire = more end to end resistance. This is combated by increasing the diameter of the copper, since electrons flow over the surface of the wire...not through "the middle". Greater surface area is the whole reason why stranded wire is used in some applications.

Now with copper prices being at an all-time high, upgrading any existing cable should be looked at with a critical eye. For a CAT6 "upgrade", you will not only have to replace the cabling, but the patch panels, patch cords and every single jack as well. Add in installation labor, and I think that cable replacement in an existing CAT5e environment is no longer a compelling argument.
 
I have yet to see a valid argument (backed by facts and data) to upgrade an existing facility from 5e to 6.
We have all new facilities wired to 6, but leave the 5e facilities alone.
If we recognize a need for any connectivity greater than 100Mbit between nodes, it is usually in a data center, and we can install a higher rate blade in a switch and wire gig patch panels for which ever rack requires the gig connectivity. Or, we just run fiber patches between racks and run off that.
 
It may seem like I'm bagging on CAT6, but I'm not. The only real point I've tried to drive home (and help the guy who posted) is that upgrading to CAT6 makes good golf course conversation, but it doesn't make money sense.

I'm with robertjo24. If you're talking about adding new runs...then by all means, put in the best you can afford. It certainly won't hurt, especially if you tend to be a "through the cable across the ceiling tile and florescent lamps" kinda guy. CAT6 will be more forgiving that CAT5e in that regard.
 
I know Dagwoodsystems is only making a statement, but...

"through the cable across the ceiling tile and florescent lamps"...

IS NOT an approved wiring method and is an NEC code violation. This is covered in NEC section 800 and other articles/sections on wiring methods, placement and "workman like manner", etc.

....JIM....
 
'Tis true, SYQUEST. It's also a violation of the English language to say "through" when one means to say "throw". I was actually silly on two points!

Thanks Jim!
 
Anyone want to comment on the fact that my bosses have instructed me to start speccing and installing CAT6a across our network in all refurbs and new builds. When i first started looking into it i was sold but the more i read and digest i think we would be fine with 5e.

We do have applications running at 1gig and i suppose if they revise or revamp the application at all, we could be in trouble.

I downloaded two papers this week to give my bosses before they made a decision. One was by the TIA saying that 6a was the way forward and go for it, while the other one was by ADC Krone a cable manufacturer, who said there was no need for it ?

I think the bosses are just covering themselves under the future proof umbrella, and pretty soon now we will have our first 2 buildings done in CAT6a.

One other surprising fact was that we costed both 6a and 5e, and on a 12k job the difference was only 1.5k. However the containment is costing 40% more.
 
The Golden Rule: He who has the gold, makes the rules. If your boss wants to use CAT6, the correct response is "how soon do you need it?"

I've been more of a "there's no need for it" guy when it comes to replacement of cable in a CAT5e environment. In a new installation, however, I think one could easily make an argument for putting in the best money can buy.

CAT6 is backward compatible with CAT5e, so there's no rub there. It IS a better performing cable overall with less loss and crosstalk than CAT5e. Where it shines is the signal to noise ratio. I've read claims that CAT6 is 12 times less impervious to noise than CAT5e. And even though I'm skeptical about that number, the signal to noise ratio really becomes the biggest factor in network speed.

There's a lot of talk about cable "frequency" as well. There's "minimally-compliant CAT5e", which is tested at 100Mhz, and then there's CAT5e 350Mhz (what some call CAT5E or CAT5 'big E'). There's "minimally-compliant CAT6" which is tested at 250Mhz, and then there's CAT6A. Depending on the cable manufacturer (since it's not a standard yet), CAT6A can be 500Mhz, 550Mhz or better.

The frequency that's sometimes suffixed on the cable level describes the bandwidth that the cable is tested with. Since 99% of the networking gear out there operates at the 100Mhz band, anything "wider" than that is unnecessary in practice. It's like saying that a Ford GT40 is better than an Oldmobile 88, when the speed limit is 65MPH. True, the Ford is effectively "future proofed" should the speed limit be lifted, but the Olds is also highway compliant. In the same spirit, both CAT5e and CAT6 are capable of Gigabit ethernet. Don't ever let anyone tell you anything different. The greater bandwidth capability of a 250Mhz cable over 100MHz cable, DOES NOT equate to a doubling of throughput with today's existing network equipment. It just means that it's throughput ability could be used if future network hardware utilizes frequency as a means to increasing throughput.
 
Some of the discussion here has already addressed the future-proofing provided by the higher grade cabling. Another issue to be considered is the effective bandwidth even at current speeds. I know I saw some discussion by Anixter about the significant impact of errors on effective throughput. Seeing this discussion, I searched for that reference, but found some similar articles.

Dr. Jay Potter in a paper titled "Ethernet Over Standard Category 5 Cable" ( discusses this issue in relation to the question of choosing Cat 5e over Cat 5 cable. (His footnotes refer to several Tek-Tips posts.)

Better cable (with corresponding better installation practices) can provide higher effective bandwidth even with existing hardware by the elimination of frame errors and subsequent retransmissions.
 
I am finally going to wire up my house, a little bit. Going to use cat6. Only uses are internet, network and media center (future). Then I read about Cat6a. ANy suggestions and why about which cable to go with?
 
Kev your house has Cable, FOIS or DSL service ranging from 1/4 meg to 50 meg, averaging about 5 meg. Cat 5e will be fine until you need 10 gig ethernet around your house, say 2200 AD.

Again

Cat 5e good for 1 gig for 100 meters (328 feet)
Cat 6 good for 10 gig for 37 meters (120 feet)
Cat 6A good for 10 gig for 100 meters

Only you can know if you need more than 1 gig ethernet speed or 120 feet length.

I tried to remain child-like, all I acheived was childish.
 
I read somewhere in internetland that when doing high definiation video from your bas computer and say to a media center at your tv it would be better? oh wait, that was wireless N.

But I did read that if you can afford to put in cat6 now then do it now to prepare for the future. THus I thought it was logical.

Basically all I would be using (with Roadtunner or FIOS) is internet, networking (just a home).

So there wouldn't be any advantage to cat6?


 
My feeling is that if you already have CAT 6 cable and hardware in your possession, then there really is no harm in using it for a residential install.

If you are still in the planning stages and have no cable & hardware yet, then I would go the 5E route.
 
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