Wireguard connection very slow

Technical Support for Routers
1

I have a wireguard server set up at a residential address. It’s dynamic IP, so I use DDNS to point to the endpoint in the client configuration.

It works, but it has very slow download speed, 5 mbps. The normal speed at this residence is 50 mbps (Comcast 50 mbps plan). Both server and client are Gl inet AX1800 routers.

Is there anything I can do to make the connection faster? Do I simply need a plan with higher speeds? I’ve read that MTU can be a cause for slow speeds, but I’m not sure it applies here. I also read that asking the isp to set public ip to ipv4 only can help. Any suggestions are greatly appreciated.

2

With Wireguard, or any VPS, your maximum rate is the lower speed of either your upload or download speed. I think your Comcast plan only has a 10Mb/sec upload, and there some amount of overhead so you normally will not reach your max rate.

At times I can get almost 40Mb/sec over WIreguard using Comcast residential 1Gb/sec service, as upload rate is documented at 35Mb/sec, but normally can do over 40MB/sec, using an AR300m as my Wireguard server. I have my MTU size on my Wireguard clients set to 1280, as I travel a lot, and some places I stay will not work with the higher default MTU setting.

DDNS works fine with Comcast, and having a static IP address should make no difference in speed.

With only having a 50Mb/sec down, 10MB/sec up service, an AX1800 seems overkill for hardware.

1 Like
3

Ah OK. So it sounds like I need to upgrade the plan to get higher upload speeds at the residence in order to get better wireguard download speeds.

MTU can be set in the client configuration, correct? Do you only adjust the clients MTU and not the server?

4

Yes, I only set the Wireguard MTU on the client side, and it seems to make it much more plug and play then using the default setting.

5

40mbps on a 1gig connection sounds pretty abysmal. I have a 500mb subscription and get around 25mbps using multihop wireguard servers I don’t even own. It belongs to my VPN provider and I’m mostly limited due to only having a Mango

6

The upload rate is documented at 35Mb/sec but normally can do over 40MB/sec, which is very standard for Comcast cable, as their upload and download rates are way different. As their upload rate is my download rate, I cannot get faster then what they provide, and I’m getting almost 100% of their upload rate using Wireguard.