L2TP/IPSEC xtremely slow speeds

If someone can shed some light please.

I am running ROS (6.48.1) as a virtual machine and I cannot get between 2 locations (L2TP/IPSEC) a higher bandwidth test upload speed than 8-9Mbits.

Side (A) has a 200/200 and side (B) 60/10, I was expecting to get the full speed side (A) can give, while running the test on side (B), but like mentioned it doesn’t go higher than 8-9Mbits!
CPUs on both sides while performing the upload test, run at around 2-3%, so it isn’t a CPU resources issue.

If anyone is willing to run a quick test between his/her location and mine, please p.m. me and we can run it.

Thank you in advance!

Probably hardware acceleration related. Some encryption algorithm can be accelerated in hardware level. My office with MT 3011 can do 3mbps vs 20mbps without and with hardware acceleration under L2TP/IPSEC with 100mbps up/down link. Note the drastic improvement with hardware acceleration.
Check page: https://wiki.mikrotik.com/wiki/Manual:IP/IPsec#Hardware_acceleration

Thank you! One thing that helped a lot (per support’s instructions) was to set MTU on both sites at 1400 instead of 1492 or 1500 and/or minus 28 on both…

1400 boosted speeds to almost 90%-95% of what the internet lines can give.

I have read about HW acceleration in the past and as I am using a virtual machine , how do you activate it ? I am curious…

Have a look at HW acceleration capabilities per device model. If the combination of encryption algorithm, hashing algorithm and key length is right, HW offload should happen automatically.

Thank you !