耐克森 LANmark-6 10G 解决方案在瑞典进行的对比测试中排名第一.

Major test: 10 gigabit over copper | 

Cables of the future already here

By Lars Dobos |

The cable standards Cat 6A and Class EA are lurking just around the corner and will be able to carry 10Gbase-T, i.e. 10 Gbit over a conventional network cable. This new standard will place great demands on the quality of your network cables. We've received a bunch of cables for testing which are all supposed to be able to handle the new standards.

New cabling system standards are out in the market. These are known as Cat 6A and Class EA and will be able to accommodate the 10Gbase-T standard.

There are already cabling suppliers offering products they claim can handle the coming standards. Of course, we wanted to test the truth of these claims and so set up functional testing of the network cabling systems.


Click on the image to enlarge it.

The suppliers – Nexans, Systimax, Panduit and ADC Krone – each sent us a package with bulk cables, plugs and patch cables, and we checked that all were properly wired up and ready to be tested using our hired test equipment from Fluke Networks (DTX 1800).

We also borrowed a couple of other cable set-ups, Cat 5e and Cat 6. We could use these to compare the differences between Cat 6A and older cabling standards. We only used these two cables as a reference standard since they're not of the same standard as the ones we tested.


Worth knowing about cable performance

Just as we suspected, the performance testing was a close-run thing, with small differences between the competitors. The first thing we’d like to point out is that all four systems in both sub-tests clearly came out above the lower limits stipulated for the coming standards for Cat 6A and Class EA. The sub-tests consist partly of a test of permanent links (PL) and partly a test of channels (ch).


Nexans and Panduit are neck to neck a little ahead of the rest of the pack, while Panduit is still a fraction better than Nexans with a higher NEXT value. Systimax also did well with a solid margin of 3 decibels over the limit (0). We’ve no idea, though, why the reference cable for Cat 6 performs worse than that for Cat 5e, but we can merely say that the latter isn’t up to handling 10Gbase-T.


Permanent links mean outlet-to-outlet or panel-to-outlet (in our case, 15 metres between the outlets), with monofilament conductors inside the installation cable. Channels mean an installation (permanent link) plus patch cables in both points at the ends of the permanent link. These kinds of cables have each been three metres' long in our test.

Overall, the tests run under Fluke Networks DTX 1800 show that Nexans has the best of it in the test, but it’s by such an incredibly small margin that they beat runner-up Panduit. In practice, both systems are about equal in terms of performance.

Panduit gained a lower value in the sub-test of RL over a channel, where they came last, while Nexans came second. In the other three sub-tests, these two competed for first or second place. They even share the first place for RL over permanent link. Both Nexans and Panduit performed well or very well - more than 3 decibels above the limits for the coming standards for Cat 6A and Class EA.

Systimax is a clear mid-ranger which neither really shines nor really disappoints. It also performs very well, being over three decibels above the limits, but lags a fraction behind Nexans and Panduit. To say that Systimax is an inferior choice compared to the two better performers would, on the other hand, be an exaggeration, since Systimax is also a good choice for Cat 6A.

In two cases – NEXT and PL with permanent links – the cable system from ADC Krone does not manage three decibels over the limit, but it does at any rate make it over the limit. The two reference cables show with all desired clarity that they will not function well as carriers of 10GBase-T.


Foil-wrapped Nexans can take a good beating

We’ve taken a long look at the external properties of the cables and their physical attributes. It’s a norm in the industry to desire as thin cables as possible, meaning they don't "bunch up" so much when bundled. The cables should also be smooth and pleasingly rigid to the touch, so making them easy to handle during installation, as well as preventing them from getting too tangled. Few issues irritate installers as much as kinked cables. The cables designed for the coming standards are all solid candidates. Both the thickness and stiffness show a striking difference compared to Cat 5e and even Cat 6 to a certain extent.

Nexans only supplies cables in orange. It would be more sensible if they at least offered a couple more discreet alternatives for those requiring them. The Nexans installation cables are 7.53 millimetres thick and thus the thinnest in our test. In their cross-section they are perfectly round. The surface is hard and matt, but still quite smooth and seems to handle a good deal of wear. The stiffness is reliable – maybe nearly too reliable. There comes a point where your feeling tells you have bent the cable far enough, and that feeling comes sooner with the Nexans cable than with the other brands we tested.



The shielding in Nexans' cables is abundantly clear as soon as you open them up. This despite the cables being labelled as utp or more precisely, f1/utp. The contacts are also shielded, something which makes the connector feel a bit more solid than the others.


Despite the stiffness, or perhaps just because of it, the Nexans cables only have a slight tendency to sag. Inside, the cable consists of a plastic separator separating the pair of conductors, the conductors themselves (where the brown colour is confusingly like the orange), a surrounding metal foil, a fibre braid, as well as a monofilament metal wire. In other words, the Nexans installation cable is shielded despite not being marketed as such.

The Nexans patch cables are considerably thinner, only 5.97 millimetres. The explanation is interesting and to be found inside. Nexans has actually opted to shield each pair of cables separately and so the patch cable lacks the usual plastic separator in the centre. Both the contact bar and patch contacts are shielded with metal filling. Unfortunately, the patch contact features an (in our view) irritating rubber guard over the barb. The patch cable is also stiff. This is more of a disadvantage in this case as the cables are often run in narrow cabinets and racks.


Systimax offering easy to bend

Systimax supplies cables in seven different colours, including a pair in discreet grey and white. The installation cable is 7.86 millimetres thick, completely round and with a shiny, smooth surface. The cable feels less scratch-resistant and durable, the soft exterior can easily be scratched and with a bit of effort we can make holes in the surface with a nail.

On the inside, the Systimax gives us a surprise. The usual plastic separator is absent; instead there is a flat plastic belt in the centre of the cable. The belt is twisted as a spiral and is relatively thin. Around it thus wind the leads with two pairs on each side of the belt. How this can achieve the prevention of crosstalk between the pair is a mystery to us, and certainly a secret at Systimax. Neither do we see any component designed to screen the crosstalk between cables. The secret is probably to be found in the casing, whose inside is grooved like a rifle barrel and this raises the distances to the conductors in adjacent cables. It also makes the cable a little thicker than the Nexans.



Systimax offer an interesting design since it lacks a central separator, instead having a twisted plastic tape which separates the conductor pair so that two pairs remain on one side of the tape, and two on the other. Clearly it works as the cables achieve a good NEXT value.


The Systimax cable sags more than the Nexans one. We were sometimes required to straighten out kinks in the cable and turn it the right way in our test rig. Compared to the Nexans, though, it allows considerably more bending and stretching.

Systimax patch cables are 7.65 millimetres thick, i.e. about as thick as the installation cables. This cable, just as the installation cable, consists of a central spiral band wound with two pairs of conductors on each side. Then the cable has two casings, where the inner one has the same grooved interior as the installation cable. The patch cable is admirably flexible and pliant, but not as much as a typical Cat 5 cable.

The patch contacts appear ridiculously small compared to the cable, but function well. The barb features an assisting pressure plate on the rear edge of the contact – a great feature.


The poorly-marked Krone and its issues

ADC Krone supplies a blue cable with a matt surface which slides easily and feels hard like the Nexans one, but which is more easily damaged. The choice of colour isn’t so clever considering both the text and markings are also blue, especially as Krone doesn't appear to offer other colours. The text on the cable is really difficult to read, especially once the cable has been dragged around the floor for a while.

The outer structure is spiral-shaped, therefore not entirely round as the Nexans and Systimax. The shape, owing to the branches of the central divider, is asymmetrical, with one pair of branches measuring 5.5 millimetres and the other 7.5 millimetres. This in turn means the diameter of the entire cable varies between 6.75 and 8.63 millimetres, or 7.7 millimetres on average. Presumably more air is allowed to flow between spiral-shaped cables, the likelihood that they dovetail into each other in an optimal way appears small.



Krone’s installation cables and patch cables are very similar in their designs. The difference is the larger central separator in the installation cable, or to be more precise, it has a more obvious asymmetrical profile.


The solid central separator makes Krone’s cable feel quite rigid - nearly as rigid as the Nexans one. Unfortunately, we get the feeling that Krone's cable twirls around and sags quite a lot when using it in our rig. Kinks and bends sometimes become a nuisance and we often need to turn the coil over in order to allow the cable to easily roll up or unroll. Its flexibility is quite good, even if the Krone is somewhat less flexible than the Systimax, despite its stiffness. It’s easy to scratch the surface but an advantage is that scratches and nicks are lighter than the surrounding surface, making it easy to spot them.

Krone’s patch cables are identical in structure to the installation cables. The difference is to be found in smaller dimensions - 6.21x7.68 millimetres – something caused by smaller dimensions of the central separator. The patch cables are a little on the stiff side in order that they can function optimally in the connection points and racks. The flexibility could be better since at present it feels a little too susceptible to sharp bends. The cable contacts are transparent, somewhat larger than Systimax and have a very similar barb design.


Panduit cable shielded and sensitive to scratches

Panduit offers its cables in three colours: blue, grey and white. The white we received for the test is the thickest cable we tested at 7.51x9.47 millimetres. The fact that they are spiral-shaped with a filler wire is also something we think contributes to these cables bunching up more than the others we tested. Compared to a Cat 5e cable, you can reckon on these cables that we tested bunching up twice as much, which certainly applies to the Panduit.

The surface is matt, soon gets dirty and feels quite susceptible to damage. Just as with the Systimax cable, we can damage the outer layer with nails.

Despite its filler wire, these cables are not especially rigid but are on a par with the Systimax, in other words, quite soft. The tendency to kink and twist is not as great as with the Krone. The surface has so-to-speak some friction against itself.



Just as the Krone, the Panduit has a spiral-shaped profile, but in this case it's nothing to do with an asymmetrical central separator, but is the result of Panduit adding a filler wire with a monofilament copper conductor. Whether this conductor has a shielding effect we’ll not venture to say, but it does contribute to increasing the distance between the cables in a bundle.


Inside, the Panduit cables consist of a symmetrical central separator, the conductor pair, a fibre braid, the filler wire and the casing itself. The filler wire has a monofilament, rather thick copper thread but this has no conducting function, at least not with the contact bar we used. On the other hand, it presumably has a shielding function.

The 6.88x7.32 millimetre thick patch cable only has a mild spiral form. The surface feels very similar to the installation cable, if somewhat shinier. The pliancy is decent but not the best – for example, the Systimax cable is a better choice in this respect. The interior offers another surprise: the conductor pairs are wrapped around the central separator and then there is a very thin plastic film, followed by metal foil, followed by a further plastic film and finally the casing itself. It appears that Panduit has chosen to have the metal foil exist in its own little space between the layers of plastic film.

The cable contact is the best in the test with a solid design and with a barb which is extended and curved like a roof – very user-friendly.


TechWorld conclusion

Overall, we think the Nexans is the best combination of solid performance with good handling properties. It’s not perfect, but neither is it bad in any area. Panduit is on a par in terms of ease of use, even if in a slightly different way to our second choice. In terms of performance, there’s little to choose between the two.

Systimax doesn’t offer equally high performance, but is easy to handle, and offers functions and finesse. Krone puts in a performance above the limits, but not so high above them. Krone cables are not as easy to handle as the others, even if the Krone product is not bad in any way.

There is very little to choose between the products – we had to give a great deal of thought to marginal notes to pick a winner - which is Nexans.