The distance between server room to computer room is within 150 meters.

The computer room has 50 computers. The computers will be used for YouTube watching, Skype, e-mail, etc...

All the computers will be linked with Ethernet cables to 2 switches in the computer room. Then the 2 switches will be connected with single CAT6 to computer room.

Can CAT6 support this?

I know CAT6 has 90 meters maximum length limit.

So I will put a switch in the middle.

Is this ok?

  • 5
    No Ethernet cable has a 90m maximum length. Almost all are 100m, but some are shorter based on the speed they're operating at. You haven't mentioned what speed anything is running at, which makes me think you have no idea what you're doing and should hire someone who does (my apologies for being blunt). Server Fault is for Professional System Administrator (et al) only.
    – Chris S
    Oct 10, 2014 at 4:48
  • 2
    150m is easily supported by fiber.
    – cpt_fink
    Oct 10, 2014 at 5:05
  • 1
    @ChrisS You are right. I have little knowledge on this. The Contractor came out with a Quotation which the cost is very high. The contractor is doing, what they care first is earning money. I cannot totally trust them without doing own research. Thats why I'm doing my own research before agreeing the contract. Current looking for information from different source.
    – mjb
    Oct 10, 2014 at 5:37
  • @mjb As per site rules: if you do not know what you talk about, do not ask here. superuser.com deals with users that try to deal with computers.
    – TomTom
    Oct 10, 2014 at 7:11
  • I'd highly recommend getting a second quote if the first seems out of the ballpark. If you're on a constrained budget make sure you mention that, most projects they'd be able to cut a corner here and there and drop the price dramatically (doesn't mean you'll get the same level of quality or functionality, but sometimes the people making the budget don't/can't account for that). For a price example, a 150m OM3 Fiber costs me ~$150, the 1000Base-SX xvers cost about that much each as well. 100m of Cat6 costs ~$75. Installation would be the larger cost in either case; YMMV.
    – Chris S
    Oct 10, 2014 at 14:10

1 Answer 1


A simple Google search could have given you what you needed. From Wikipedia:

When used for 10/100/1000BASE-T, the maximum allowed length of a Cat 6 cable is 100 meters or 328 feet. This consists of 90 meters (300 ft) of solid "horizontal" cabling between the patch panel and the wall jack, plus 10 meters (33 ft) of stranded patch cable between each jack and the attached device.

When used for 10GBASE-T, Cat 6 cable's maximum length is 55 meters (180 ft) in a favorable alien crosstalk environment, but only 37 meters (121 ft) in a hostile alien crosstalk environment, such as when many cables are bundled together.

YouTube does 1080p at 4Mbps. A Skype HD video call takes up to 1 Mbps for each attendee. Email and other browsing typically do short, high bursts and have very little consistent data transfer.

If all 50 people were watching YouTube videos and doing Skype calls simultaneously it would only take up to 300Mbps. You'll have the other ~2/3rds of that 1Gbit link left for other usage.

I doubt you'll see that kind of traffic, but if you do you'll want to implement Qos.

Since the contractor is already running a line you might as well have him run 2 or 4 lines total. That way if you do ever exceed the limit of that single line you can do link aggregation to increase the throughput. It's also nice to have an extra line just in case one goes bad.

And, yes, you can put a switch in the middle of long runs to extend the connection. Alternatively you could run fibre and use fibre to copper converters at each end if your switches don't have SFPs.

  • What are the limits of tons of extensions? Are there any?
    – Pacerier
    Oct 19, 2017 at 8:11

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