What are my options in this type of small network setup?
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Those white boxes look like cable doublers(economisers). Horrible nasty things that need to be burned!
They are used to send two 100Mbps Ethernet connections down a single run of cat 5/6. The cable has 8 wires but you only need 4 for 100Mb Ethernet. The problem is there's no way to know at the far end that only 4 conductors are connected and if you try to connect Gigabit Ethrnet to it it won't work. Worse it may report that it's connected at 1000Mbps and then just not ever send any traffic! Many Gigabit cards have technologies to detect and prevent that scenario but some don't.Steve
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Worse it may report that it's connected at 1000Mbps and then just not ever send any traffic!
I have had exactly this - wondering why the Gb did not actually go. Someone saving money 15 years ago installed dual outlets at each office desk point, but there was just 1 ethernet cable behind, 2 pairs for each outlet. But no fancy cable doubler thingy at the patch panel end, the 1 cable was split into the 2 x 2 pairs and each group of 4 wires punched down to the rear of each RJ45. From looking at the RJ45s at each end there is no clue that there are only 4 wires connected.
In those days it was only Cat5 cable anyway, so that would have been not up to Gb standard anyway, even with all wires connected. -
So do you install one on each end? One from the desk and another in the comms room?
I can understand why you would want to install at a desk to increase the number of ports. But why would you do it in a comms room when there's plenty of ports available.
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Sorry to drift you off-topic for a bit!
At the comms room end you need 1 RJ45 for each RJ45 at the desk, so you can patch each to its own port on a switch. -
So do you install one on each end? One from the desk and another in the comms room?
I can understand why you would want to install at a desk to increase the number of ports. But why would you do it in a comms room when there's plenty of ports available.
It makes no sense. You would think at the back end both "ports" would go to the same switch port, which wouldn't work at all.
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So do you install one on each end? One from the desk and another in the comms room?
I can understand why you would want to install at a desk to increase the number of ports. But why would you do it in a comms room when there's plenty of ports available.
It makes no sense. You would think at the back end both "ports" would go to the same switch port, which wouldn't work at all.
Splitting drops used to be a lot more common, it goes like this:
2x switch ports go to either 2x patch panel ports that are are split on the back and output to a single cable, OR they would go into one of those little "doubler" devices, which then plugs into a single patch panel port that maps to the actual run. Either way in the MDF/IDF/whatever end it ends up two cables by the time it hits the switch, but just one on the run back to the target office/room.
In the actual room you again would either have a doubler into a wall jack OR two jacks that are split on the back.
Terrible practice, but some people are penny pinchers and cable runs can add up (in materials and labor), sometimes there are also physical limitation.
If you're running one cable, you may as well run at least two, plus a lead of some sort… but then again it's probably been half a decade since I have done much wiring and more like 15 years since I've seen a split run like that.
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Duh. Of course you need them at both ends.
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Yeah but unless those devices do something other than split the wire pairs into two groups, it could be a mix of those devices, split jacks, or some other wacky implementation. Either way, it's worth tracking them all down and eliminating them.
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They could merge voice and data onto one cable run and all sorts of wacky stuff.
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They could merge voice and data onto one cable run and all sorts of wacky stuff.
You could even do ADSL data plus voice on a single copper phone line, but I digress :P
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Yeah but unless those devices do something other than split the wire pairs into two groups, it could be a mix of those devices, split jacks, or some other wacky implementation. Either way, it's worth tracking them all down and eliminating them.
My guess is that it was put in to save money and I probably won't be able to get rid of them unless they spend money on additional cabling.
You could even do ADSL data plus voice on a single copper phone line, but I digress :P
In UK we get this quite often with our ADSL lines. I remember my internet getting cut off sometimes when the phone rings.
edit: Going to lock topic as it is getting too long and off topic now.
