RT-AC86U Ethernet Speed dropping with 384.14_2

[Aircub]

I have a Ethernet cable running between my Virgin Broadband router that is in Modem mode and my Asus RT-AC86U. Up until the last few updates I had 1 Gbps WAN speed between the two, now it drops to 100 Mbps.

Strangely if a run a cable test on the Ethernet cable to the Virgin Box and then replug it back in the speed it is back 1 Gbps, after a few minutes the unit shows Internet disconnected before dropping back down to 100Mbps.

I have CAT5E cable about 60m between the two.

Any ideas why now its dropping the speed?

 

[ColinTaylor]

Even though Cat5e cables are meant to be good for up to 100m if you're using a cheap cable it's possible that there's too much signal loss to maintain a gigabit connection. On the other hand the cable might be good but the Ethernet chip in either the modem or the router might not be up to the job (these things are built down to a price).

I'm not sure how you can prove this theory other than replacing the cable or temporarily moving the router near to the modem and connecting them with a short patch lead.

If you think the issue is with the Ethernet port on one of the devices you could insert a cheap gigabit switch in front of it to act as a sort of buffer.

 

[Woody]

I had the same problem as you - going Gigabit 10m (60m is really pushing it - LOL) between an AC86U and a TPLink Gigabit switch.

In the end, one of these was the solution: https://www.amazon.co.uk/gp/product/B018KH7O4E/?tag=smallncom-21

 

[Aircub]

.

If you think the issue is with the Ethernet port on one of the devices you could insert a cheap gigabit switch in front of it to act as a sort of buffer.

Can I ask why putting a switch at one end helps, just wondering.

 

[ColinTaylor]

Can I ask why putting a switch at one end helps, just wondering.

One can only speculate. It might be an incompatibility between different manufacturer's chipsets. It could be that the resistance drop caused by such a long (or cheap) cable means that the router or modem doesn't have enough power to drive the signal at the correct level. Using a quality switch with its own independent power supply could help.

Whatever the reason, there have been quite a few reports that these kind of "illogical" problems can sometimes be resolved with an additional switch.

 

[Aircub]

One can only speculate. It might be an incompatibility between different manufacturer's chipsets. It could be that the resistance drop caused by such a long (or cheap) cable means that the router or modem doesn't have enough power to drive the signal at the correct level. Using a quality switch with its own independent power supply could help.

Whatever the reason, there have been quite a few reports that these kind of "illogical" problems can sometimes be resolved with an additional switch.

Care to recommend a switch...??

 

[ColinTaylor]

Something from Netgear or TP-Link is pretty safe. Definitely not anything from D-Link.

If I just wanted something cheap and simple I'd probably go for a Netgear GS305 or TP-Link TL-SG105S.

EDIT: Before spending any money I encourage you to test the link with a shorter cable. If as you said the problem appears after only a couple of minutes it would be fairly easy and quick to prove whether or not it's a problem with the long cable.

 

[Aircub]

Ok, I seem to have cured the problem, it would appear that one item on the router a Mobile phone signal booster running at 100mb was causing the problem. I have disconnected this and I have a 1Gbps connection on the WAN cable and so far it has not dropped out.

Not sure why this would cause a problem, but happy now.