Slow fiber ethernet speeds with Balance 20x and CenturyLink

My ISP is CenturyLink on the initial setup tech used a CL router and the speeds were good - 940 down, 890-900 up. However after I switched out with the Balance 20x, my speeds dropped to 190-210 down, 400 up.

My config is basically from a site that instructs how to set up the Surf SOHO.

Also to note that CL is a PPPoE connection and required a VLAN tagging ID to be entered in WAN otherwise I had no connection.

PPPoE is almost certainly the culprit here, it is quite CPU intensive on the Peplink hardware in my experience and even the really high end boxes can struggle with high-speed PPPoE WANs. I’m sure if you were watching the CPU utilisation on the 20X you’d see it getting pretty busy when under load.

To test this theory is it possible to have the CenturyLink router configured so it handles the PPPoE session and hands your Balance 20X an IP either statically or via DHCP, with or without NAT shouldn’t make much difference it is just to prove whether or not the PPPoE connection really is the cause of the problem here.

I did notice very high CPU loads while running a speed test after connecting the 20x to the CL router (which was on PPPoE) over DHCP. It got as high 83% (yellow bar) during download and as high as 79% during upload.

However, this wasn’t the case when I had the ethernet plugged directly into the 20x with a PPPoE connection. CPU load never broke 10% while running a speedtest.

Ok… so in answer to my previous point regarding PPPoE performance was the throughput higher when you had the CL router handling the PPPoE side of things?

As I said, I have seen Peplink struggle with high-speed circuits where PPPoE is handled on the Peplink side, there are other posts on the forums that also reflect this issue.

If you’re still not getting good performance when the CL router is just handing you an IP and there is no PPPoE configured on the Peplink then I’d start to look through the config to see if there is anything that might explain that - a support ticket at that point might also be worth a shot.

I forgot the most important part! Yes the speeds were much higher, just slightly below the speeds the CL router reached. About 900 down, 800-890 up. So thanks for your help!

I do have one additional question - how secure is the current setup versus going with the 20x alone?

I’d not worry too much to be honest, the CL router is likely just doing NAT in front and means in some respects if you want to let traffic in directly such as a port forward you’d have to expose the ports on the CL router and then also on the Peplink.

Gotcha. Thanks for your response!

You probably mean PPPoE. Both routers are logging in the same way, so it makes sense that there is a setup difference between the two. Once the negotiation/login is complete, that process no longer hogs any bandwidth. What is the reasoning for the big difference?

Looking around the internet, there are plenty of complaints about CL FTTH dedicated CL routers, etc. Mostly they do not allow disconnecting their own router, so you immediately get a double NAT situation with 2 routers in the path. The CL router is set up specifically to deal with CL fiber service and the unique details are not easily available. I was able to return the CL router and everything ran perfectly on a SOHO with no speed reduction. I would be certain of the router setup before blaming CL. Using a WAN VLAN tag is how they separate their in-home services and will not affect the WAN speed.