Wired, outdoor PC cameras?

You can (a) look at the wire colors in the cable through the transparent connector and match them to the chart, or (b) plug the cable into a cat5 cable tester.

Assuming that whomever made the connector followed the wiring T568 suggestions.

Ohmmeter.

Check whether 1,2 on one end, goes to 1,2 on the other end. Or, whether 1,2 on one end, goes to 3,6 on the other end.

The first is straight thru.

The second is crossover.

Of the eight wires (four twisted pairs), four of the wires are "legacy" material. 1,2 and 3,6 pairs were used on 10/100BT for the wiring. The remaining wires would not be doing anything.

On the legacy stuff, a TX pair was wired to an RX pair. An RX pair was wires to a TX pair. That was the four wires.

Whereas GbE is bidirectional on eight wires total.

And the waveform on GbE is "beautiful". It's PAM5. It would look even nicer, if we could see the PAM5 eye diagram on the Tektronix digital scope. Very colorful.

( )

Paul

Actually, a few minutes ago, I looked the one cable that I could easily find. Yes the connector was transparent and yes I could see that they were the same so it wasn't a crossover cable.

But are the connectors always transparent? My memory might be wrong, but I didn't think so.

Thanks, but I don't think I need to do that. See the other reply I'm about to send.

My memory is apparently wrong. It just occurred to me that it would be very easy to look at the cables coming into my router.

Yes, the ends of all four of those connectors are *all* transparent. What must have confused me is the part of the connector next to that end transparent part is opaque, colored the same as the cable itself.

Ugh! Just do a visual check. Put the two cable ends side by side. If the colors match, pin for pin, it's straight through. If not, it's most likely a crossover, but could also be miswired (not likely). You can use the colored pictures found online, as well.

AKA 8p8c

Agreed.

Not sure what you're saying there. Gender has nothing to do with it. The two wiring standards (568A & 568B) apply equally to both genders, although patch panels, which are almost always female, are normally wired straight. The crossover role, if needed, is normally left for the patch cable, the link between the patch panel and the piece of equipment.

Right, using either 568A or 568B cable/pin assignment.

Agreed.

You ought to see the eye diagram for 400Gbe and 800Gbe with PAM4.

You don't have to know which format they are to know if they are crossover. Hold both ends next to each other and see if the colors are in the same order. If they're not, it's crossover. If they are, it's not.

Yes, as others have said. Thanks. I hadn't realized they were transparent.

Most _plugs_ are for stranded cable, they are intended for loose flexes (patch cables) between equipment and between equipment and fixed wiring (i.e. wall socket or patch panel). Most _sockets_ are for solid cable, intending for the fixed wiring through ducts, walls, ceiling etc where the flexibility of stranded cable isn't needed. Solid cable is simply a bit too stiff for patch cables, any bending forces translate through to the contact (even through the strain relief) and I've found they work loose in short order.

More common is sockets that can accept either solid or stranded cable. Solid is to be preferred for fixed wiring that is expected to make up the bulk of a run, since it has slightly lower losses than stranded, although in my home network I use stranded exclusively. If I had installed it all in one go I would probably have bought a 100m or 305m reel of solid, but the fixed wiring has gone in over time so it's a lower immediate cost to buy a 10, 20 or 30m patch lead and lop the ends off for the bare cable. But then the longest run in my home is 28m, and even that follows a very circuitous route, well short of the 100m limit so a little additional loss is acceptable.

Also while I'm posting I'll just pick up a terminological note elsethread. It's a crossed or crossover cable in a networking context, never rolled or rollover. The latter is generally construed to mean a cable wired 1-8, 2-7 etc. Used a lot in serial (RS232) over twisted pair which these days is something of a niche thing in a home environment, but still very widespread in commercial and industrial settings.

You're quite right, not sure what I was thinking ...