How to establish if a 566ms average response time is any good for the server

I'm wondering what a maximum (practical) ping response time might be. As far as I know, there isn't a max defined anywhere (TTL, but that's hops, not time).

Theoretically, the time between echo request and reply can be long. From a quick glance at RFC 1122 I don't see any formal constraints here.

Practically though, there's a threshold value after which lack of reply will be treated as no reply at all (timeout). The specific value depends on implementation:

• In Windows it's 4 seconds.

• With iputils implementation of ping it seems to be 10 seconds - not sure about it, as it's not stated in the man page, but the code says something like this:

   #define MAXWAIT         10              /* max seconds to wait for response */
  

Ping responses longer than that are equivalent to no responses at all. So, I think it's safe to assume this to be the practical limit.

One thing to note - I'm talking here about ICMP only. If you meant some other "ping" (for example delay between some application-specific request/response), it will probably differ completely.

You could try tcping to measure latency to port 3389 of the remote server.

tcping.exe is a small console application that operates similarly to 'ping', however it works over a tcp port.