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New Member

VoIP over fiber network


This is my first post. I hope I am at the correct forum.

My firm will be moving to a larger facility in the next few months. As budget is not an issue I want to install fiber throughtout our lan network.

My question is:

Is there a way to use the unused Ethernet port on the PCs the plug in the Cisco 7975 Voip phone and route back to Cisco router/switch.

Hall of Fame Super Gold

Re: VoIP over fiber network

Say again in other words? What is that you want to do, and what a PC port has to do with fiber?

Most important, are you a network engineer or an end user asking ?

VIP Super Bronze

Re: VoIP over fiber network

Anything is possible; however, I would not recommend this:

  • The workstation's NIC will not provide power over Ethernet. This will require you to use local AC/DC power bricks. Unless you plan on putting a UPS at every desk, this would eliminate the phone's ability to stay up during a power failure for emergency calls.
  • You are relying on the workstation to be turned on and Windows (or whatever OS) to act as a bridge into the data VLAN. If the PC is off or having difficulty, your phone will now suffer with it.
  • You will not be able to put the phone into a separate voice VLAN.
  • The cost of fiber SFPs, the additional power requirements, and lower port densities makes this a financially unjustifiable decision.
    • If you are looking for speed, Gigabit Ethernet will perform just fine.
    • If you are looking for electromagnetic interference avoidance, shielded twisted pair will solve this.
    • If you are looking for distance coverage, adding remote switch closets will solve this.
  • Fiber patch cables are much more susceptible to damage which will increase your support desk calls.

I'm always glad to hear when customers say "budget is not an issue"; however, don't waste money. I can think of a dozen other things to invest in instead of fiber to the desk.

Please remember to rate helpful responses and identify helpful or

Re: VoIP over fiber network

Well said and ditto!


New Member

Re: VoIP over fiber network

Thank you for your prompt and excellant reply. I'll do it

your way. But, we will connect servers,Sans etc. with fiber.

I really appreciate your help.

ken wood

Camarillo CA