Are there any conventional tiers of RTT latency? (eg., 0-30ms, >30-60ms, ..) The only non-arbitrary basis for that that I can see at present is classes of applications based on latency, such as VOIP vs HTTP https://en.wikipedia.org/wiki/Traffic_classification#Typical_traffic_classes is the nearest I've found, and it's based on logical application rather than latency, although that's implied Traffic classification :: Traffic classification is an automated process which categorises computer network traffic according to various parameters (for example, based on port number or protocol) into a number of traffic classes. Each resulting traffic class can be treated differently in order to differentiate the service implied for the user (data generator/ consumer). Typical uses Packets are classified to be differently processed by the. Interesting traffic introspection product read BTW: https://www.sandvine.com/downloads/general/sandvine-technology-showcases/traffic-classification-identifying-and-measuring-internet-traffic.pdf don't think there is kelly.. jitter is usually referenced more than rtt.. as rtt can vary depending on distance i used to disapprove of networks with more than 0.5 msec jitter in normal operation. but there are just way too many factors.. That's quite a tight tolerance but in a very round about way, things like 2 msec jitter mean that there is more network load, which means the chances of upstream congestion issues in the near future is higher yeah - things like virtualisation, coalescing etc can add a little bit of jitter which doesn't necessarily impact I like how high jitter exposes providers with inadequate network capacity at certain times of a day. It's also why I value throughput monitoring the thing is it's usual for jitter to go up a little as networks are getting into higher utilisation %'s.. which can suddenly lead to severe issues well i like the idea of small file throughput monitoring still I dislike over-subscription personally That's what I mean vultr sydney has had congestino issues since it started, but it's in the upload direction... well it was in both directions for a while. Up/down is a great distinction. I'll make a note of that but it varies where it's from, a lot of weird issues, ... if you want somewhere weird to test from err uploading to vultr is bad i mean rather than downloading to it err downloading from it which suggests either people torrenting from it, or it sharing bandwidth with some isp work loads :) the problem is most providers have more than one provider, and providers can have different issues in different locations also it depends what you're doing, i stopped doing throughput monitoring mostly when 2 or 3 megabytes/sec was easy because after that it stops mattering a lot more.. Latency, jitter, packetloss, throughput up/down. Can you think of other fundamental attributes of network performance? if you're getting 300k/sec it matters a lot more mmomentary network outages My idea for that was to have 1MB file transfers frequently, with 10MB less frequently, and 100MB infrequently Thoughts? well i do 200k and i find it hilights any issues fine and i do 10mb manually sometimes That's what she said!! That's good to know That's what she said!! i don't really think you need to do more than that if it takes 2 seconds to download 200k when it usually takes 1 second there is degraded network performance it doesn't really matter how fast you get now days True it's more important to catch issues and doing lots of 200k donwloads can still burn off 200gb of data ors omething Jitter is the standard deviation of a series of RTTs, correct? http://www.cisco.com/c/en/us/support/docs/voice/voice-quality/18902-jitter-packet-voice.html actually that site sucks jitter is basically the difference between median and mode i think, but don't hold me to that In plain terms, do you look at jitter as the standard deviation? To identify how much the latency varies anyone know what it means when a thinkpad is stuck on battery light and z with circle indicator the screen turned to static like pixels the last time it was on. I really hope it isn't dead maybe a short? that's just a random guess though