I am connecting an outdoor LTE modem to my 2926 via ethernet but am getting lousy speeds from the line. I just connected the modem directly to my MacBook Pro, let it pick up the public IP address and got 97mbps down, 31 up. 2 minutes later connected to the 2926 I get 10 down, 12 up. I was suspecting 3 of throttling the speeds but my direct connection shows that to be very far from the case.

The only difference I can think of is the MTU, which is 1500 on my MacBook but, using Path MTU Discovery the 2926 wants it at 1468. Setting it to 1500 on the 2926 makes no difference, so the issue is surely somewhere else.

Can anyone help?

Have you tried the 2926 set to MTU 1468?

Hi thanks for replying. Yes, that’s how it was set after I let the router test the MTU for me. It seems to make no difference, which is odd.