0

I've just installed a Linksys WRT1900 AC router and a Linksys 4008 8 Port Gigabit switch.

My setup goes Cable Modem -> Router - > Switch and all wired devices hang off the switch.

I noticed the internet speed on my pc (Directly wired to switch) has dropped from around 200mbps to 20mbps as soon as I moved to the new equipment. Just as a test I plugged the PC straight into the modem and the speed returned to 200mbps. I then put it back in the switch and it was still reporting 200mbps on speedtest.net. I then moved some cables around to different ports and it dropped back to 20mbps.

At this point I decided the switch may be faulty so removed the switch and plugged everything straight in to the router. Still 20mbps. I moved the PC cable to a different port on the router and it then went back to 200mbps.

My internet connection speed it normally a solid 200mbps and does not change. There definitely seems to be some sort of issue with ports on the router/switch but it seems random or at least I can see no pattern. I've tried swapping network cables and can see no indication a given cable is faulty.

I can't imagine both the switch and router are faulty so my question is what could cause this behaviour?

Edit : The router LED's are indicating all devices are connecting at 1000mbps

Edit 2 : One thing I've noticed is if when it's slow I disable the adapter in Windows and re-enable it then all is good. Could it be that me changing ports and not releasing/renewing the ip causes that could cause speed issues and the disable/enable fixes that?

5
  • What is the backplane speed of the switch? This would limit its combined speed across all ports. Each port may go up to 1Gb, but the internals might only have something like 2Gb across all ports simultaneously.
    – Hydraxan14
    Dec 20, 2016 at 21:11
  • Is your Ethernet cable home-made, kinked, or sharply bent, or hung vertically unsupported for a great distance? Dec 20, 2016 at 21:55
  • I've tried several different cables, they are all short runs and free of kinks.
    – Gavin
    Dec 20, 2016 at 22:06
  • Do you have QoS enabled?
    – GeekyDaddy
    Dec 21, 2016 at 13:01
  • Try modem -> switch -> PC and see if speeds change.
    – GeekyDaddy
    Dec 21, 2016 at 13:04

1 Answer 1

0

Unless both the router and switch are corrupted, than I would say one of the devices may be faulty or at least a cause for the slow connection. Before switches were introduced, ethernet hubs were mainly used, and by design could influence speed since each packet was transmitted to every device on the hub.

Switches on the other hand isolates traffic between the two devices on the network. The actual connection speed of the ports should not exactly be an issue either, since you had mentioned you are able to get your max desired speed when plugging your PC in to one of the ports.

Ethernet switches have no influence or involvement in whether or not any device gets an IP address; they operate only at the MAC address layer. You probably have a defective component somewhere in the chain; either a bad Ethernet cable or port, or you've mis-configured your router.

Perhaps, to be safe, preform a factory reset on your router and wipe the configuration. Than test each port once again, and see if the problem still occurs.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .