Cat 5 for 1000BaseT network 2

[BobFroeh]

I have a bunch of Cat 5 installed and we are considering using some Gigabit switches with Gigabit NIC's. Has anyone tried using this setup over existing 100BaseT wiring???

 

[GMgerry]

No guarantees but it will work. I have run it about 100 feet just to get a base line on funtion. I have don ethe same with cat 3 running 100BaseT, Again it works but I would not trust it in a production enviroment.

 

[jimbopalmer]

Cat 5 parts/cable is rated for 1000baseT, assuming it is terminated to spec. It will be a wonderful chance to see if the installers really were professional.


I tried to remain child-like, all I acheived was childish.

 

[GMgerry]

Will your gigabit switch be transmiting over all four pairs or just two?

 

[BobFroeh]

Will your gigabit switch be transmiting over all four pairs or just two?

I thought gigabit required all four. Or can it run either way??

 

[SYQUEST]

My understanding is CAT 5e is approved for 1000BASE-T, NOT CAT 5!

You may get it to link with some equipment, but the bandwidth available would be very questionable on CAT 5.

Lookup the manufacture's specs on the cable you are using, the more bandwidth, 250mHz or more, the better the 1Gb will be. I would only use the higher grade CAT 5e for best results.

....JIM....

 

[mikeydidit]

Worst case scenario turn the port off from auto negotiation and down to 100.

If i were planning a gig connection I would run 5E 350.

Hell, there are no rules here - we're trying to accomplish something.
Thomas A. Edison

For the best response to a question, read faq690-6594

 

[PainOfDeath]

I'm not a cabling guy, but the installer who did one of our offices maybe 6-7 years ago used Cat 5 (not 5e). I upgraded the switch a couple years ago to gigabit and am running everything on gigabit without trouble. Some of the runs are over 100 ft as well.

Everything negotiates to 1 GBPS, but the true throughput may not be optimal. And yes, gigabit requires all 4 pairs. Make sure you are using 5e rated patch cords at least, I had a cheapie on one workstation and it would only sync up at 100 MBPS, replaced it and now it works at 1 gig. I only use gigabit now where I can, 100 MBPS is so 1990s

 

[GMgerry]

Just making sure everyone was paying attention. The other reason I asked about the 2 or 4 pairs is that back in the cat 5 days many installers were just that installers. Many even questioned why install 4 pair when your only using 2. Point was that they didn't care much if the non data pairs worked, tested good or even terminated them. I have seen that to being one of the problems that cat 5 didn't work.

Something else to be aware of when using gig with VoIP. Yes gig uses four pair so how does the phone get power? Don't forget that you lose the power pair when converting to gig. When ordering a gig switch it is worth looking into the cost of POE. There was no cost differace with we ordered a test switch.

 

[VoIPFANATIC]

who runs a voip phone at a gig?

and if you do why?

and you can also power voip phones locally at the station side with a 48v power brick.

speaking from a Cisco world.

802.3af defines two types of power source equipment: end-span and mid-span.

End-span refers to an Ethernet switch with embedded Power over Ethernet technology. These new switches deliver data and power over the same wiring pairs - transmission pairs 1/2 and 3/6.

Mid-span devices resemble patch panels and typically have between six and 24 channels. They are placed between legacy switches and the powered devices. Each of the mid-span ports has an RJ-45 data input and data/power RJ-45 output connector. Mid-span devices tap the unused wire pairs 4/5 and 7/8 to carry power, while data runs on the other wire pairs.


my 2 cents.