Cat5 and Cat5e cables, and ISP speeds

[ibex333]

So here I am studying for my Network+ exam... I am currently learning about the myriad different cables, their speeds and specs, and I am pretty confused about one particular thing...

According to my study materials the cat5 cable is rated for 100Mbps and the Cat5e is rated to 1000Mbps... Correct?

Well, if this is so, why is my Verizon DSL ISP providing the cat5e cable for my router when even the cat5 would be able to handle these pitiful DSL speeds?

Hell even the cat3 cable would be by far more than enough, no? This doesn't make any sense. I don't know of a single ISP in the US that would offer a connection of 1000Mbps down. There isn't even one that would offer 100Mbps! Even OOL's cable service only offers 15Mbps down and 2Mbps up. With "BOOST" I think they offer up to 30Mbps down.


I must be missing something vital here...

 

[yoda291]

because cat5e is cheaper, particularly at the quantities verizon likely purchases it at.

You have to recall, the diff between cat5 and cat5e is the twists in the cable. So for verizon to get you cat5 cable, some manufacturing plant would specifically need to tool their equipment to make cable that will pass a cat5 rating, but purposely fail to qualify as cat5e. Plus, what's a tester to do if they should accidentally make a cat5e cable? Toss it? It's just easier to constantly crank out cat5e because it's all backwards compatible and they can just constantly use the same set of tests to quality check it.

 

[ScottMac]

The primary difference between Cat5 and 5e ("e" is for "Enhanced") is that all four pair are qualified for high-speed data on 5e, and only the green and orange are qualified on Cat 5 and below.

Cat5 is sufficient for GigE, but since GigE uses all four pair to concurrently send and receive in both directions (all four pair send, and at the same time, all four pair receive), having all four pair qualified makes 5e better suited for Gigabit Ethernet.

Cat6 improves on that, Cat6a improves on it further.

The farther up the "cat" scale you go, the tighter the specifications for proper termination become. If you don't terminate it properly, you end up with expensive Cat-nothing. Well-terminated Cat5 is better in all regards than poorly terminated Cat5e, Cat6, or Cat6a.

The twist ratios play into the cable's ability to meet the Category specifications, but there is no hard, fast rule ... there's more to it than just twisting the pair tighter. Other things, like the relationship of one pair to another, the twist of the pair-to-pair, the insulating material, the sheath material, spacing of the conductors ... it's all engineered by that specific manufacturer to a design that they created that is meant to achieve a set of goals.

If they meet or exceed the goals, they earn the certification.

Cabling from each manufacturer will be different in how they achieve the goals for specification.

 

[ibex333]

I think I did not ask the question properly... What I mean is, what was the point of even coming up with cat5 and cat5e when ISPs only offer so little "bandwidth"? (hope I'm using the right word) It's sort of like making a jet that will fly at Match VII speeds, but doesn't have the technology to keep the pilot alive while going this fast. It's great if someone makes a jet like this, but it will still be entirely useless until someone can actually fly it. This is probably not the best comparison, but you get the idea...

Can you tell me if there is any network technology out there that actually sends data between computers at 100 or 1000Mbps? Maybe in a government LAN or something?

 

[yoda291]

Originally posted by: ibex333
I think I did not ask the question properly... What I mean is, what was the point of even coming up with cat5 and cat5e when ISPs only offer so little "bandwidth"? (hope I'm using the right word) It's sort of like making a jet that will fly at Match VII speeds, but doesn't have the technology to keep the pilot alive while going this fast. It's great if someone makes a jet like this, but it will still be entirely useless until someone can actually fly it. This is probably not the best comparison, but you get the idea...

Can you tell me if there is any network technology out there that actually sends data between computers at 100 or 1000Mbps? Maybe in a government LAN or something?

most local networks operate at those speeds and higher actually. If anything, there's a good demand for even faster links. The internet is not the end-all be all of networks.

For instance, when I am using my home file server, I'm pushing way past 100Mbps as I have gigabit links all through my home. People who have media center PCs can easily break 100Mbps throughput and these are just rinky dink home network provisions.

Even small business networks nowadays are transferring data at gigabit speeds regularly to file servers and locally hosted web apps. Large enterprises often bond together multiple 10G fiber links on their backbones and sometimes, even this is insufficient.

On top of all this, even a modest datacenter can run you a full 100 or 1000 mbps connection to the internet for servers and hosting content and people requiring multiple gigabit links is not uncommon.

Here's something to ponder in case this all seems far fetched. 100Mbps is only 12.5 MB/s under artificial perfect conditions. Filesizes measured in multiple gigabytes are not uncommon.

 

[Modelworks]

Another thing to consider is it is just easier on accounting.
Much easier to order CAT5E for everything than it is to order CAT5 for some things, then CAT5E for others, and make sure one type is only used for one thing and not the other.

When I worked for GE we often used cabling and wire that was way over spec for the connection.
It was done simply because everything else on the harness needed the higher spec and it was just easier to use one kind for all.


Take a look at pc power supply for example.
All the wires carry different currents , but one size is usually chosen for all, just for simplicity.

 

[jlazzaro]

there's no point in having specific cable types for every application. that's like going to the gas station and them having a different type of gas for every make and model car.

in our world of standards and interoperability, it just makes sense. the higher the cable rating the better; after that its up to the devices on each end to negotiate the operating speed. this way, a single type of cable fits most of scenarios.

 

[kevnich2]

Supply & Demand. Right now, supply is high for Cat5e and growing for Cat6, it's cheaper to order because they make it so plentiful. Even though internet speeds aren't that high, LAN speeds need to be. My own home network, I transfer multiple gig files regularly, 100mb would be too slow for me right now. I can't wait for 802.11n to be ratified so my wireless is faster than what it is.

 

[JackMDS]

To most End-User Networking means nothing the only thing since they are possesed with is Internet Speed (while th Hunner is porking in the suburban garage ).

However ISPs are just a small segment of the Networking world, cables are evolving according to Networking needs that get faster and better.

Price is establish by market demand and dominance.

So what ever is cheaper easier to get Now, the ISPs are using, next year they would give CAT6.

 

[MrBlahh]

Do they even make cat 5 stuff anymore? If I remember correctly its not recognized by the standard gods anymore.

 

[cmetz]

ibex333, try pricing out a cat3 patch cable. They're not cheaper, they're more expensive. Supply and demand. cat5e is where most of the demand is, so you can get it cheap... if you're a wholesale, volume buyer, it's going to really be the cheapest choice.

Also remember that cat5 is needed for 100BaseTX, and 100BaseTX is needed vs. 10BaseT for any speed exceeding 10Mb/s. So if you have a 11Mb/s DSL connection (hypothetically), they need to have a 100BaseTX port and you need a cat5 cable in order simply to get more than 10Mb/s of speed over that connection.