TP-link Deco speed drop when connected via 1gb network

2013 · 24 Aug 2021 at 21:42

Could someone help I don't understand why but when my deco S4 Is connected via the network I get 93mbps speeds but when I connect directly via the virgin router I get 293mbps.

I'm using a tp-link TL-sg1024d

andy_mk3 · 24 Aug 2021 at 23:01

Is it definitely connecting at 1gb?

2013 · 25 Aug 2021 at 01:37

andy_mk3 said:
Is it definitely connecting at 1gb?

I hope so, how do I check?

Turn · 25 Aug 2021 at 02:39

Is the Deco being plugged straight into the Virgin Hub?
And if not, do you have switches, powerline, etc in between and are they Gigabit?

Just having a quick guess it could either be that the cable is damaged causing it to sync at 100Mbps, or a switch your Deco is going through isn't gigabit (unless you're plugged straight into the Hub).

2013 · 25 Aug 2021 at 02:44

0007 said:
Is the Deco being plugged straight into the Virgin Hub?
And if not, do you have switches in between and are they Gigabit?

Just having a quick guess it could either be that the cable is damaged causing it to sync at 100Mbps, or a switch your Deco is going through isn't gigabit (unless you're plugged straight into the Hub).

Ok ive tried both direct via VM router and cat6 rj45 faceplate which is connected to the switch.
via the router I get near my full VM speed but when I connect via the faceplate I get around 100mbps. Im using the same cable and the switch is a tp-link TL-sg1024d

the-evaluator · 25 Aug 2021 at 08:46

Sounds like the problem is with the cable run from the router to the faceplate. 100Mbps connections use 2 of the 4 pairs whilst gigabit needs all 4 pairs to be working. Check the terminations at both ends.

2013 · 25 Aug 2021 at 11:11

the-evaluator said:
Sounds like the problem is with the cable run from the router to the faceplate. 100Mbps connections use 2 of the 4 pairs whilst gigabit needs all 4 pairs to be working. Check the terminations at both ends.

I dont completely understand but I assume you mean I need to connect 4 cables from the router to the rj45 which connect to the switch so the other rj45s can get gigabit ?

the-evaluator · 25 Aug 2021 at 11:26

2013 said:
I dont completely understand but I assume you mean I need to connect 4 cables from the router to the rj45 which connect to the switch so the other rj45s can get gigabit ?

Not quite. An ethernet cable contains 4 pairs of cables which are twisted together (that's the TP part of UTP for example - Unshielded Twisted Pair) so when you remove the other cable sheath you see something like this:

There's an orange pair, a green pair, a blue pair and a brown pair. Each pair is made up of solid colour cable and a striped coloured cable. In total there's 4 pairs of cables so 8 wires.

For 100Mps ethernet only 2 pairs (so 4 wires in total) are needed - the orange and green pairs if you're using the widely used cabling standard. For gigabit all 4 pairs (so all 8 wires) are used. If you are only getting 100Mbps down a cable then it's possible that 1 or more of the individual wires aren't connected or are damaged.

So check both ends of the problematic cable. How are they terminated? If the terminations are OK then it's possible that the cable is damaged somewhere along its length.

2013 · 25 Aug 2021 at 11:41

ok, I get it, So ill need to check how the guy I hired to setup the network did this, hopefully, he used all four or at least he has not cut them off (huge problem if he did).

the-evaluator · 25 Aug 2021 at 11:46

It would be an extremely unusual thing to do to cut any of the wires out. Changes are it's just a bad termination. Can you get some photos of how the cable is terminated at both ends?

the-evaluator · 25 Aug 2021 at 11:49

Actually, it's worth confirming that the link is running at 100Mbps when using that cable. When you're connected via that cable check the properties of your network card and see what is shown for the link speed.

wellibob · 25 Aug 2021 at 12:11

Deco S4 units are limited to 100 Meg. They cannot do gigabit speeds. S4 units are useless in today's world really.

Edit my bad. It's the E4 that's not gigabit not the S4.

2013 · 25 Aug 2021 at 12:44

the-evaluator said:
It would be an extremely unusual thing to do to cut any of the wires out. Changes are it's just a bad termination. Can you get some photos of how the cable is terminated at both ends?

Thanks for the help here are some images https://prnt.sc/1qhtv63 https://prnt.sc/1qhtvlu https://prnt.sc/1qhtup7

the-evaluator said:
Actually, it's worth confirming that the link is running at 100Mbps when using that cable. When you're connected via that cable check the properties of your network card and see what is shown for the link speed.

ill check that once im bak home

wellibob said:
Deco S4 units are limited to 100 Meg. They cannot do gigabit speeds. S4 units are useless in today's world really.

Im not sure thats true https://prnt.sc/1qhtyzd

Orcvader · 25 Aug 2021 at 13:04

According to this, have you tried updating the S4s to the latest firmware? Might be a firmware bug locking the ports to 100mb.

the-evaluator · 25 Aug 2021 at 13:26

2013 said:
Thanks for the help here are some images https://prnt.sc/1qhtv63 https://prnt.sc/1qhtvlu https://prnt.sc/1qhtup7

The photos don't really help. Can you remove the plastic covers over the punchdown points, they should just pull off.

Which switch port is connected to that cable?

2013 · 25 Aug 2021 at 17:59

Ok Ill try and get a better image asap

2013 · 25 Aug 2021 at 19:04

Orcvader said:
According to this, have you tried updating the S4s to the latest firmware? Might be a firmware bug locking the ports to 100mb.

Could be I did recently update but it was a stable ver, Ive try again with router and im getting 300+.

the-evaluator said:
The photos don't really help. Can you remove the plastic covers over the punchdown points, they should just pull off.

Which switch port is connected to that cable?

I have no Idea which port is connected to which as he did not add labels to it but he did send me a email which ill need to dig out
here is a new image https://prnt.sc/1qibxlr hope its better

**Update**

the-evaluator · 25 Aug 2021 at 19:32

Still not a good enough picture and we'd need to see the termination at both ends of the cable.

If you don't know which port that cable is going to, take a note of which ports are showing are showing a link when it's connected then disconnect the cable and check the ports again. The one that is no longer showing a link is the port in question.

2013 · 25 Aug 2021 at 19:51

the-evaluator said:
Still not a good enough picture and we'd need to see the termination at both ends of the cable.

If you don't know which port that cable is going to, take a note of which ports are showing are showing a link when it's connected then disconnect the cable and check the ports again. The one that is no longer showing a link is the port in question.

Im afraid that is the best I can get as it does not have much cable to pull out

Here are the images ive took no4 is the deco s4 no6 is vm https://prnt.sc/1qie8rc https://prnt.sc/1qie88c https://prnt.sc/1qie778

edscdk · 25 Aug 2021 at 20:01

Deco s4 is 100meg, thread linked earlier suggests its firmware but the device is sold as 100meg..