ASUS RT-AC66U-New Modem caused Drop in Speed

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Allen1970

New Around Here
I have had a Cable internet connection for years. The AC66U did just fine. Fiber optic internet became available and I just switched over. That meant a new modem/router combo. The modem router combo runs n as it's fastest wifi. However, after testing with and without my AC router, my speed is 3x to 4x better with just the modem/router.

I did find that the QoS was slowing me down, that helped.

Also, Asus themselves suggested testing different control channels. That did little to the speed.

Looking for some more things I can try to help bring the Asus back up to speed! ; )
 

OzarkEdge

Part of the Furniture
I have had a Cable internet connection for years. The AC66U did just fine. Fiber optic internet became available and I just switched over. That meant a new modem/router combo. The modem router combo runs n as it's fastest wifi. However, after testing with and without my AC router, my speed is 3x to 4x better with just the modem/router.

I did find that the QoS was slowing me down, that helped.

Also, Asus themselves suggested testing different control channels. That did little to the speed.

Looking for some more things I can try to help bring the Asus back up to speed! ; )
Is your old AC router still as fast as it was before you upgraded ISP service to its fiber gateway?

OE
 

Allen1970

New Around Here
No, it's multiple times slower.

It shot up quite a bit when I adjusted the QoS, but it was still under 100 Mb/s for both uploading and downloading.
 

Allen1970

New Around Here
I did not change the new modem/router to bridge mode.

However, I switched off the radio on the new modem/router because I hooked up the Asus to use it as the router
 

Ronald Schwerer

Very Senior Member
I did not change the new modem/router to bridge mode.

However, I switched off the radio on the new modem/router because I hooked up the Asus to use it as the router
So unless your AC66U is configured as an AP, you've got double NAT and DHCP.
Unless you actually need the combo modem/router's wired ports, you'll get better performance setting it in pass-through (bridged) mode.
 

Allen1970

New Around Here
Yes, thank you, that makes sense. I thought I could just "turn off" the radio for the modem/router and it would act like just a modem!

Unfortunately, this modem/router combo (ZYXEL C3000Z) isn't as user-friendly as the Asus to switch to bridged mode ( It's called Transparent Bridging).

I have found some documentation on how to do it (https://www.akadia.com/services/zyxel_transparent_mode.html)

But I am going to continue to search for other instructions that may be easier to follow.

Plus, I need to wait until tomorrow when everyone else is out of the house so their internet isn't interrupted!

Will either ask for more help as I start working this solution or let you know everything works.

Thanks again!
 

OzarkEdge

Part of the Furniture
Yes, thank you, that makes sense. I thought I could just "turn off" the radio for the modem/router and it would act like just a modem!

Unfortunately, this modem/router combo (ZYXEL C3000Z) isn't as user-friendly as the Asus to switch to bridged mode ( It's called Transparent Bridging).

I have found some documentation on how to do it (https://www.akadia.com/services/zyxel_transparent_mode.html)

But I am going to continue to search for other instructions that may be easier to follow.

Plus, I need to wait until tomorrow when everyone else is out of the house so their internet isn't interrupted!

Will either ask for more help as I start working this solution or let you know everything works.

Thanks again!
I switched a Zyxel C1000Z to Transparent Bridge Mode to work with a 68U. I recall the (simple) instructions were on the ISP website. The trick is logging back into it, if ever required. As I recall, given its IP 192.168.0.1, you need to assign a static IP 192.168.0.2 (255.255.255.0) to your PC adapter and wire directly to the Zyxel... probably to the only LAN port that works in bridge mode.

OE
 

Val D.

Very Senior Member
It shot up quite a bit when I adjusted the QoS, but it was still under 100 Mb/s for both uploading and downloading.
Is it the original RT-AC66U with MIPS CPU? If Yes, then QoS disables the hardware NAT acceleration and your router won't go any higher than about 150Mbps, depending on what else is running on it. Check what is says in LAN -> Switch Control section, if I remember correctly the location. Also, make sure the link between your modem and the router is actually Gigabit.
 

Allen1970

New Around Here
UPDATE: Switched CL routers (long story) to ActionTek c3000a.

Followed the instructions on ISP website for the ActionTek modem/router to set to bridge mode.

They also gave me settings for my router that I will hook up to that modem.

It didn't work for me. For some reason the Wi-Fi signal was not getting to the router (the Asus).

Should to Asus be in Access Point mode to work?

The ISP gave me a VPI/VCI setting. Where is that setting on the ASUS router? Is there one?
 

Allen1970

New Around Here
Sorry, I have switched topics. I will start a new thread.

Ronald, I am attempting to use the ActionTec as solely a router and connect it via Ethernet to my own router.
 

Ronald Schwerer

Very Senior Member
But you said the instructions were to set the ActionTek c3000 to bridged mode. If it is, then it just passes (with minimal local processing) WAN to LAN (probably only LAN port 1 is active). So in bridge mode, it isn't a router. Your ASUS will be the router for wired and wifi.

AFAIK, Virtual Path Identifier (VPI) and Virtual Circuit Identifier (VCI) only apply to the DSL modem, not the (ASUS) router. Not being familiar with DSL, I'll let someone else step up here.
 

Allen1970

New Around Here
Sorry for the confusion. Yes, that was what I was trying to say. I will use the ActionTek as a router and my Asus as the router

Here are the instructions from the ISP website I followed:
On ActionTek

WAN
Transparent Bridging

VLAN
Untagged

ON ASUS ROUTER:

ISP protocol : PPPoE
PPP username : [email protected]
PPP password : xxxxxxxxxxx
VPI/VCI : 0/32

I would love to find someone out there who could tell me if something is missing from the instructions. As I said, they didn't work for me.
 

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