I have had a couple of older Surf SOHO and decided to try the new MK3. I set it up with the factory default configuration to test it before deploying and have been getting mediocre routing performance around 120 Mbps.
I have a Arris SB8200 DOCSIS 3.1 cable modem with the 200/10 Mbps Comcast service tier. My baseline test was directly connecting my Mac to my modem via ethernet. That was performing at about 230/12 Mbps on IPv6 speed tests. IPv4 tests were slightly slower in the 215/12 Mbps range.
I then rebooted the cable modem and connected it via Ethernet to the MK3 WAN port, and my laptop via Ethernet to the MK3 LAN port. First thing I noticed is the MTU defaulted to 1440, not auto. I set it to auto and it negotiated 1500. When running the same speed test service, I am getting about half the download speed through the MK3 that I was when directly connected to the modem, in the neighborhood of 120/12 Mbps over IPv4. I also tried to change the WAN link speed from auto to 1000Gbps full duplex and got the same results. I upgraded the firmware from 6.3.3 to 7.0.2 and reran the tests with the same results.
What routing speed should I expect from the MK3? If this maxes out at around 120 Mbps, there isn’t much point in upgrading from the previous version. Any suggestions on other things I should try?