Our hosted servers are experiencing periods of very slow network access. During these periods pinging from any of our servers to the default gateway results in ping times of up to 500ms (instead of the normal 2-3ms). There are no packets lost.
The ISP is claiming their network is OK and the problem must be with the hosting service. The hosting service guys claim they have nothing at level 3 and everything according to them is OK.
I'm think our servers are connected to a switch which is connected the default gateway over a shared ATM line. Traceroute doesn't show any routers on the path.
Before changing my service providers, is there anything I could check that might explain what is causing this issue?