I am not sure if this is the correct community, please let me know if I got it wrong. I am new to PoE. I've inherited a network where in one office there is a PoE wireless access point. This device is connected on the other side to a PoE switch (in the data room) that is about an 80' Category-6 run away.

In this particular office, I need to hardwire two devices above and beyond the existing PoE WAP. One of those two additional devices is an IP phone (which I want to power via POE), while the other is a computer workstation. I think I should be able to run an ethernet cable from the IP phone to the workstation, if need be, which could cut down the cable requirements from 3 to 2. However, both of those are still POE.

Should I just bite the bullet and run new network cables back to the data room 80' away, or is there a way to "split" the one network cable in this office into three cables, two of which need to be connected to my new hardwired POE devices and the third back into the existing PoE WAP?

I recognize the problem here may be power transmission/continuity.

By the way, if need be, I can run the IP Phone with a regular data cable (no PoE) because I have a DC power adapter for it. I do, however, prefer to run it PoE. I have to run the AP via POE since there is no power in the vicinity of the WAP.

Any insights/advice is greatly appreciated!

  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
    – Ron Maupin
    Commented Aug 15, 2017 at 1:25

4 Answers 4


Splitting a 4-pair UTP cable is completely non-standard, especially with PoE. You will never get a split cable to pass the category suite for that cable category (in your case, Category 6). If you want to run gigabit ethernet over the UTP cable, you will need all four pairs to do that.

The correct way to do this is to run a minimum of two UTP cables to each faceplate. Your WAP is probably going to be in the ceiling or on a wall, and it should have its own dedicated cable, in its own cable pathway.


I would buy an inexpensive POE switch, connect it to the 85ft CAT6 run, then connect both the AP and PoE phone to it. The Cisco SG200 is a decent choice.

FYI - This will add complexity to your setup. The proper way would be to just run another cable from the closet.

  • are you saying something like this: ExistingPoESwitch->85ft CAT6 run->CiscoSG200->WAP & PoE phone Is this like a PoE passthrough type of thing?
    – user30227
    Commented Sep 4, 2016 at 17:58
  • Never mind, I just remembered you don't have power by the AP, you need a power outlet for the SG200.
    – D007
    Commented Sep 4, 2016 at 18:30

I would run at least 1 (2 preferable for future use or if your phone doesn't have a computer port on the bottom) cat 6e from your current switch to the phone and computer location. It will offer consistency and and will offer features you need to set it up properly like vlans, voice options, etc.

  1. If you try splitting pairs you may be able to get a 100mb connections but you will chance burning up the POE (power).

  2. If you put another switch at the cable that is there now you will add a failure point to a WAP that probably services several users. That's not a deal breaker though. Also, you would most likely need a switch capable of vlans so you can run your data vlan, phone vlan and any vlans you have for wireless SSIDs. If you don't mind getting a quality switch and programming and securing it properly this could be an option. If your really only adding 1 phone and 1 computer this adds complexity and confusion. If this is a good area to extend your network this could be your opprutunity to do it right.

  3. Running a cable to a currently available switch port programmed as a trunk port or access port with voice features is the "normal" and "clean" method for the situation you've described. Set up the vlans on that port and you should be good to go.

I hope this helps. If you need any otter info let me know.


Some IP phones also have a passthrough port. If this is the case, you can connect the IP phone to the switch so it gets PoE and then daisy chain the PC off the phone.

Two possible problems:

1.If the phone develops a fault, the PC's LAN connection may be affected

2.If you need to run the phone / PC in separate VLANs, this is more problematic (but generally still achievable)

Otherwise, it depends on your environment and the amount of time / effort / cost you're willing to invest. The 100% best answer is to run additional cables back to the comms rack. This will work.

In the past I have split a CAT5 cable to connect two devices (you need a send and receive pair per connection) and this will work up to 100Mb/s although it needs some creative cabling.

Regardless, if you need to connect 3 devices this is not an option. If you've got to run one cable, you might as well run 2 (or three, or more) to give you more flexibility later on.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.