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Re: WNDR3700v2 not 100M/full duplex

SoleX
Aspirant

WNDR3700v2 not 100M/full duplex

Hello,

I have a 100 mbit internet connection. My router only connects to it at 100M/half.
When the PC is plugged in directly and forced to 100mbit full duplex i have 12,5 mb/s speed, else it is crap.
The same crappy speed is now acquired with my new router (correctly configured with ISP ip-settings).

How do i force my WNDR3700v2 router to use 100M/full ??

Thanks in advance!
Message 1 of 15
Simon0
Novice

Re: WNDR3700v2 not 100M/full duplex

100Mbps WAN is still not so common, is your WAN 12.5Mbps? eg. I have a fairly new gateway from the ISP and the connection rate between the router and the gateway is still 100Mbps, the gateway out to the Internet is 3Mbps (what I'm willing to pay for)... I can upgrade to 24-32Mbps, though.. but it's not worth the extra cost...
Message 2 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

Yes i have a 100 mbit WAN internet connection. Although I cannot use it at the fullest as the router auto negotiates @ 100M/half instead of 100M/full.

When I force the PC @ 100mbit full duplex and no router I obtain the maximum speeds.
When the router is inbetween the speed is only nearly 10 mbit.

What are my options?
Message 3 of 15
quagmire
Tutor

Re: WNDR3700v2 not 100M/full duplex

Does this summarize?

1) Modem (model?) connects to LAN at 100 Mbps/Full Duplex.

2) WNDR3700 auto-negotiates that connection as 100 Mbps/Half Duplex

3) Your PC also auto-negotiates as though connection were 100 Mbps/Half Duplex, but if you force the PC to Full Duplex, it runs at Full Duplex.

If the above is correct, then there is a problem with either the cable or the modem.

Can you try a different cable between the modem and the router? Does that help?
Message 4 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

1) Modem (model?) connects to LAN at 100 Mbps/Full Duplex.
Direct connection to switch in university campus, indeed 100 Mbps @ WAN port of router

2) WNDR3700 auto-negotiates that connection as 100 Mbps/Half Duplex
WAN port status: 100M/Half (I cannot force type of duplex so yes: auto negotiate)

3) Your PC also auto-negotiates as though connection were 100 Mbps/Half Duplex, but if you force the PC to Full Duplex, it runs at Full Duplex.
No, PC-WNDR3700v2 LAN (with 2 PC's) is a gigabyte full duplex network and runs perfectly.

If the above is correct, then there is a problem with either the cable or the modem.
The cables are OK. A friend of mine has the same connection (same building) with fast routing. With his equipment+laptop+cables @ my "wall-socket" he found the same speed issues as I did.

Can you try a different cable between the modem and the router? Does that help?
Been there done that
Message 5 of 15
Simon0
Novice

Re: WNDR3700v2 not 100M/full duplex

Ah, I think I understand... Many universities still have a few legacy switches that were quite expensive at the time. They are relatively old and may not be compliant... Having to "force" duplex is not ideal. Are you able to contact the university IT staff and ask to have your port "switched" to a different port or even better to a different network switch. They should be in the same "rack", so it should be easy for them. Their racks usually have a mix of newer as well as older switches, so your probably on a legacy switch. Most switches made in the last decade are now Gigabit-type.. (most school still restrict the speed though).

Also, connect the WAN port of your router to your PC (as a test only) to see if it negotiates at Gigabit or 100Mbits (duplex or half-duplex) speeds... just to narrow down if it's a failing WAN port on the wndr3700.
Message 6 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

Hello Simon,

I have already tested the WAN port. It does switch to 100M/full when connected to another 100 Mbit device.

Your explanation seems to be similar with my situation. I will send an email to the IT with your suggestion.

Thanks in advance
Message 7 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

Hello,

I have contacted our IT "service" and they simply tell me to force duplex to 100 mbit. But the router does actually work perfect at my friends appartment @ 100M/Full auto negotiate.
They also told me the switch works as it should.

And so the problem still exists.

- Can resetting the switch solve the issue?
- Can I manually force duplex to 100M? With 3rd party firmware?

Thanks!
Message 8 of 15
Simon0
Novice

Re: WNDR3700v2 not 100M/full duplex

Thoss lazy University IT staff... They really should change the port at least. If you can get full speed at your friend's room, but you are still experiencing slowdown even if forced, then you really should insist that they do more diagnostics.

Btw, how are the shape of the wires on the wall jack... corroded, bent, missing a wire, etc....
Message 9 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

Indeed, its really frustrating.

We have also checked the direct connection socket in the meter with my friends laptop directly connected: same issue. With his router: same issue.

- I'll check the sockets for bad wires.

- Can I use 3rd party firmware to force the router to use the 100M/Full protocol instead of 100M/Half?
Message 10 of 15
Simon0
Novice

Re: WNDR3700v2 not 100M/full duplex

3rd party firmware on the wndr3700 will have no effect on this matter

most universities in the old days use expensive corporate class "smart" switches that has ALOT of ports, some were proprietary with modified firmwares to support large port #/vlan/bandwidth control/duplex control. It may even be a configuration issue with those smart switches, as the defaults were half-duplex.

I think the IT guy is just lazy, ignoring problems, rather spend his/her time on their laptop making money from their website while on the job Smiley Very HappySmiley Very HappySmiley Very Happy
I remember several gov dept. fired quite a few people for wasting their time on eBay.. firewall logs prove that they spent nearly 6-8 hours on eBay or facebook, but nowdays people use their 3G connected smartphone/pad/laptop to cheat work hours and not get caught.

You really should go to your IT university's main IT website and send a few e-mail concerning this matter to the "supervisor/director/etc of IT".. and you'll see things happen rather quickly.
Message 11 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

So I have checked the sockets and they seem to be fine.
When I connect an older router's LAN port in the meter with my WNDR3700v2 they connect at 100M/Full. This means the cables in my appartment are fine. And so the problem is located beyond my reach.

I have sent an email to the housing. Let's see what they have to say.
Message 12 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

Called today, still looking for the problem. Yeah right Smiley Tongue
Message 13 of 15
SoleX
Aspirant

Re: WNDR3700v2 not 100M/full duplex

FINALLY The connection is fixed. Got a different port on the switch as it was corrupt (duh).

Thanks for the help.
Message 14 of 15
quagmire
Tutor

Re: WNDR3700v2 not 100M/full duplex

Thanks for coming back to follow up.
Message 15 of 15
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