When using IPv4 Class A Private network ssh becomes slow

[stingraze]

When Parallella is using IPv4 Class A Private network IP address (10.11.12.13), ssh becomes very slow.

What I mean is: When using a switch or a WiFi router without any connection to Internet, Parallella's IP address falls back to 10.11.12.13 .
That is okay, and I set my laptop's IP address to 10.11.12.14 to be able to ssh to the Parallella. I can connect to Parallella using ssh but it becomes VERY laggy. (Some inputs take 20-30seconds to respond)

I was wondering what the cause is, since Parallella connected to WiFi router with connection to the internet can obtain private class C network IP address (192.168.1.x), and laptop can ssh to the Parallella without any problems.