Sanity Check: Uplink/Upload Problems - UDP & Streaming Audio

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I just want to confirm the reason why Streaming Audio (in Windoze Media Player) actually still works even when I have 100% packet loss in my background ping...

AFAIK Streaming Audio normally uses UDP packets instead of TCP packets, now UDP does not involve sending ACKs like TCP does. So with UDP it doesn't matter if packets get lost along the way, however with TCP lost packets means no ACKs get sent for the lost packets, which then results in retransmissions, which consequently results in a longer time to transfer data, which results in slower speeds.

Assuming the above to be correct, and putting aside the download signal fluctuations (signal from base-station to UT), does this prove that most of the problems I'm experiencing (mostly very high packet loss) are related to upload signal? In my opinion the problem is not my UTD sending to the base-station, I believe it is these amplifiers at the base-station that presumably amplify the signal they receive from the UTz...

Any thoughts...?
 
Did the pings ever work to the site you were pinging? They are sometimes firewalled.
Or where you pinging your tower?

Also, in quite a lot of networks pings are given a low priority and could well be dropped if the network is very busy.

But indeed a good theory that since the udp stream continued, you were receiving but not able to send. What was the link info in your iburst terminal showing at the time?
 
With the way that WBS have messed with iBurst it has been necessary to have a continuous ping -t 196.30.31.100 (or other IP) running in order for your connection to actually work, if you don't do this (at least on some base-stations) your connection stalls for 60..90 seconds.

When that ping shows a stream of Request timed outs, it means that packets are being dropped on the upload from UT to base-station - and browsing, email in fact anything that uses TCP connections falls over, while incoming UDP traffic (download UDP packets) continues.

I have pasted quite a few examples of such pings in the sticky Communication thread, and there is also an example in the sticky Problem Reports thread as well.
 
I tried to have a look there now, but there are about 500 messages and I dont have time to wade! My own experience of Iburst to date is on average a 1% packet loss that surprisingly does not cause problems and a latency far better than ADSL.
I actualy have a linux program monitoring and graphing ping times, packet loss and http response times to about 5 locations. Uptime on the PPPOE interface is 107 minutes right now, this is also a UTD Ethernet connection. Signal I can only monitor from the lights (anyone know how to monitor signal via ethernet interface?) and they is more often than not 5, but drops to 3 now and again and to one sometimes, but not for long.

However if I move the UTD 10cm from where it is, service is shot!

In another location with lower signal I have seen the UTD die a few times while doing a big download from tucows.is.co.za. Had to power cycle it. I should test that further and see if any definite conclusions can be drawn.
 
This is a problem that only seems to happen on certain base-stations (namely Bryanston & Northcliff), so UTz attached to other BSz do not know what it is like & what the signs are.
 
yeah UDP being connectionless is fun for streaming, but I have noticed DoS UDP floods on 3 occasions that knocked me off the net (no I wasn't on IRC or some service making the kiddies angry), and the wierd thing is on both those occasions I had an IP listed on the Bogon List, coinkydink? i think not.
 
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