Re: Something very odd on an older 2514 .

[Dean Anderson <dean () av8 com>]

I think you are hitting a performance wall in the 2514.  You can't really
expect much more than 2 x T1 performance, and then you'll hit a wall.

The 2500 series is only a 68040, (old ones are 030's) which "manually"
shuffles packets, and can't handle sustained full ether bandwidth.  If you
look closely with a sniffer, you'd see that its dropping packets.

Your FTP slows down because the TCP window is full.

                --Dean

Around 07:46 PM 1/10/2000 -0800, rumor has it that Mr. James W. Laferriere
said:
>       Hello All ,  I've just been doing a few tests on some 2514 routers
>       I had laying around .  I setup the two ether interfaces & on each
>       like the diagram below
>
>       +--------+                        +--------+
>       |  2514  |+----------------------+|  2514  |
>       +--------+                        +--------+
>           +                                 +
>         [hub]                             [hub]
>           +                                 +
>           +---------+[ ftp source ]         +---------+[ ftp source ]
>
>       I noticed a drastic lessening of expected bandwidth thru the
>       routers .  On the range of seeing only 24-25% of available
>       ether bandwidth .
>       But when I plug the two 'ftp source's into the same hub I am 
>       getting a more resonable 66-75% of the available ether bandwidth .
>
>       Has anyone any info on what might be the cause of the lack of
>       expected thru put .  Tia ,  JimL
>
>       +----------------------------------------------------------------+
>       | James   W.   Laferriere | System  Techniques | Give me VMS     |
>       | Network        Engineer | 25416      22nd So |  Give me Linux  |
>       | babydr () baby-dragons com | DesMoines WA 98198 |   only  on  AXP |
>       +----------------------------------------------------------------+
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           Plain Aviation, Inc                  dean () av8 com
           LAN/WAN/UNIX/NT/TCPIP          http://www.av8.com
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