Speed Test Results

[b1nary]

Perhaps someone here can shed some light on something I have tried to figure out for a while now

When doing Speedtests on Various ISP's with High speed connections I have noticed the following phenomenon:

Using Speedtest.net Local tests will show the correct speed lets say on a 100Mb fibre it will come up as 90Mb download
however it will show for the sake of argument 5Mb international download.

Using Iperf3 a international test will show the same low result, if I however use a multi-threaded test the Speed will go up
till it meets the correct amount as per the ISP's contention ratio.

Can anyone explain this behavior ?

 

[agentrfr]

MTU settings on your router/modem?

 

[Sinbad]

Packet loss causes low TCP window sizes, and retransmits take ages due to latency. Therefore, throughput of a single stream is severely limited. Multiple streams makes up for this in part.

 

[b1nary]

MTU settings on your router/modem?

To Be honest I'm not sure But this I have seen this at home on a 20Mb setup and work with 100Mb unfortunately
I don't have access to the Routers in question as they are managed by the ISP and connected directly to my Untangled Firewall
which I can mess with.

Edit: read up regarding MTU

running it at 1492 gives me Packet needs to be fragmented but DF set, 1400 to 1460 works fine.

 

[Dairyfarmer]

Remember the days when local servers cached everything? Then if you refreshed a page it took forever.

The "pipe" leaving the country is probably congested.