Mario,
A ping latency of 900ms is a red flag that something is seriously wrong. As an extremely loose gauge to go by:
20-50ms is extremely good.
50-300ms is average.
300-500ms is indicative of congestion or issues. "Latency sensitive" applications will start to be impacted. Others may not.
> 500ms something is probably wrong, most applications will be impacted.
> 1000ms, stop what you're dong and seek technical support, because something is jacked up.
Also, it can be helpful to watch your latency over time. Open a command prompt window (windows) or terminal session (Mac) and run a consistent ping to a remote place on the internet for several minutes. For example:
C:\> ping www.bearbulltraders.com
Leave that window off to the side where you can watch it for a few minutes. Is your latency fluctuating up and down? Does it stay flatlined for the most part? What happens to it when you join the chat room, or start other bandwidth intensive activities (like Ryan W mentions above) streaming video, etc.?
Also while this test is going on, watch for complete drops. Meaning one of the PING attempts did not respond back. This can indicate network issues as well. When you quit the ping session in Windows and Mac it should provide a summary of statistics, telling you if you have any packet loss and what your minimum, average, max, and stddev is.
For example, here's what my ping latency looks like when I'm pinging this website from the midwest US.
ping www.bearbulltraders.com
PING bearbulltraders.com (162.144.104.203): 56 data bytes
64 bytes from 162.144.104.203: icmp_seq=0 ttl=56 time=77.145 ms
64 bytes from 162.144.104.203: icmp_seq=1 ttl=56 time=76.460 ms
64 bytes from 162.144.104.203: icmp_seq=2 ttl=56 time=79.803 ms
64 bytes from 162.144.104.203: icmp_seq=3 ttl=56 time=87.118 ms
^C
--- bearbulltraders.com ping statistics ---
4 packets transmitted, 4 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 76.460/80.131/87.118/4.223 ms
And here's what my latency looks like when I reroute my internet traffic so I come from the Ukraine:
ping www.bearbulltraders.com
PING bearbulltraders.com (162.144.104.203): 56 data bytes
64 bytes from 162.144.104.203: icmp_seq=0 ttl=47 time=461.353 ms
64 bytes from 162.144.104.203: icmp_seq=1 ttl=47 time=429.296 ms
64 bytes from 162.144.104.203: icmp_seq=2 ttl=47 time=460.202 ms
64 bytes from 162.144.104.203: icmp_seq=3 ttl=47 time=453.565 ms
^C
--- bearbulltraders.com ping statistics ---
4 packets transmitted, 4 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 429.296/451.104/461.353/12.937 ms
Similarly, here's my latency when I come from Zurich, Switzerland:
ping www.bearbulltraders.com
PING bearbulltraders.com (162.144.104.203): 56 data bytes
64 bytes from 162.144.104.203: icmp_seq=0 ttl=48 time=524.932 ms
64 bytes from 162.144.104.203: icmp_seq=1 ttl=48 time=524.972 ms
64 bytes from 162.144.104.203: icmp_seq=2 ttl=48 time=522.643 ms
64 bytes from 162.144.104.203: icmp_seq=3 ttl=48 time=538.678 ms
^C
--- bearbulltraders.com ping statistics ---
5 packets transmitted, 4 packets received, 20.0% packet loss
round-trip min/avg/max/stddev = 522.643/527.806/538.678/6.347 ms
While we're at it, here's from Hong Kong:
ping www.bearbulltraders.com
PING bearbulltraders.com (162.144.104.203): 56 data bytes
64 bytes from 162.144.104.203: icmp_seq=0 ttl=54 time=431.522 ms
64 bytes from 162.144.104.203: icmp_seq=1 ttl=54 time=430.753 ms
64 bytes from 162.144.104.203: icmp_seq=2 ttl=54 time=430.885 ms
64 bytes from 162.144.104.203: icmp_seq=3 ttl=54 time=434.329 ms
^C
--- bearbulltraders.com ping statistics ---
4 packets transmitted, 4 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 430.753/431.872/434.329/1.448 ms
Notice how when I come from these places my pings require a couple hundred more milliseconds to get all the way around the planet and back. I used these as an extreme example to show that 1.) it doesn't take very long at all for traffic to get all the way around the world, and 2.) if you're having ping latency >900ms then something is wrong.
There are also 3rd party tools you can use to monitor latency, such as www.pingplotter.com which allow you to specify multiple destination targets that you can monitor over time.
Best of luck,
Uncle B