We need a dual gigabit connection to one of our customers and for the time being one of the lines has been brought online. The connection is between our DC and the customer's HQ, it's a L2 connection. The cities are roughly 420km apart.
The initial tests showed a RTT of 26ms. Since this seemed a bit high so we complained to the carrier (T-Systems in Germany). They did some tests and "optimizations" and suddenly the RTT went down to 15ms.
I know they can't break the speed of light, I also know that the speed of light in fiber is quite a bit lower than in a vacuum but still, 15 ms seems a bit high for 420km. I also assume there must be several hops along the way but nevertheless, is this what we can reasonably expect ? Should we insist that they do some more "optimizations" ?