UDP packets loss at Israeli ISPs during peak hours

UDP packets loss at Israeli ISPs during peak hours

geoffrey mendelson geoffreymendelson at gmail.com
Sun Jul 3 11:23:22 IDT 2011


On Jul 3, 2011, at 10:25 AM, Oleg Goldshmidt wrote:

> We are all familiar with UDP vs. TCP tradeoff, but I think it is quite
> irrelevant in the context. The OP sees 50% packet loss through ISP#1
> and zero packet loss through ISP#2. I do not think that one can claim
> that 50% loss is "normal" for UDP and the network works "as designed".
> The "upper" TCP will be able to cope with a relatively small loss rate
> in the lower layer, but 50% is not reasonable.


However Oleg, you are missing an important bit of information. Since  
there is no such thing as an "internet", one ISP can not be assumed to  
be at all like another. In the real world, such things are determined  
by how good the connection is from you to them, with several ISPs and  
different routes in between.

Usually it means how well does your ISP's ISP connect to their ISP's  
ISP, or even multiple levels of ISPs.

Then on top of it all, it depends upon the load on any leg of the  
trip. As an example, I used to have a VoIP provider that was connected  
in the US to an ISP with an excelent connection to my ISP. Then some  
idiot cut most of the fiber optic cables from Egypt (where all the  
Arab countries routed their data) and they scambled to get any  
connectivity at all.

Well money talks, and they were able to replace their broken  
connections with new ones and got back most of their connectivity.  
This changed the loading on the international circuits and caused the  
rates for data to go up significantly (or the data rates to go down).  
My VoIP provider's ISP re-routed their connections from dedicated  
lines across the Atlantic which they no longer could afford to shared  
circuits terminating in London.

So what was 180ms ping time became 500 or more, causing my VoIP  
connection to fail. A call to tech support, who made a call to their  
tech support, who "fixed" things.

Bottom line, as it were is that you can not compare the performance  
outside of Israel between ISPs. You actually can't compare it in  
Israel too, but that's a different matter.

Geoff.
-- 
Geoffrey S. Mendelson,  N3OWJ/4X1GM
Making your enemy reliant on software you support is the best revenge.













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