why upload with adsl is faster than 100M ethernet ?

Marc Binderberger marc at sniff.de
Fri Oct 15 09:30:35 UTC 2004

Hi Joe,

"divide et impera" :-)

Put a (FTP-)server in _your_ network to get an idea if the problem is 
with the edge device (or somewhere in your network) or on the WAN to 

The PING may not tell you much about short-term queue problems in a 
device. As Mikael Abrahamsson wrote use a sniffer (Ethereal, tcpdump, 
...) and search for retransmissions, i.e. some "breaks" in a monotonic 
increasing sequence number sequence or such.

We had a similar issue when E1 customers had been fine but customers on 
the same router with 10Mbit/s and above complained. Took us some 
memory/queue fine-tuning of the 7500 box to get it right, traffic on 
the higher speed link probably was more "bursty" and this flooded some 
buffers then.

On Oct 15, 2004, at 10:14 Uhr, Joe Shen wrote:

> Hi,
> the network path is:
>          |-(ADSL)--------\
> customer/                 --Edge_router---...---Japan
> Server
>         \-(100Methernet)-/
> So, from edge_router to Japan server the path is
> identical.

Regards, Marc
Marc Binderberger    <marc at sniff.de>

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