Hello folks @ 3000-l

Re: Secure Web Console

I received a direct reply on this topic that I thought I would share
(not identifying the author) as it illustrates using TCP timers in the
HP e-3k to workaround a mal-performing network.

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Ummm... how many times now have I said that the 3000's TCP stack is
extremely fragile under less than ideal conditions?  Eh?
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I would tend to disagree.

Code-Red Virus had an extreme impact on parts of HP's Internal
Networks and my 'work-at-home' NT machine connected over a ISDN link
was one of the infected.  I ran 2 days before finding that my machine
was one of many driving the problem... (repairs completed at 2:00
A.M. but that is another story!)

In my investigation I found for some connections I achieved a TCP SRT
(Soothed Round Trip) time of .985 (almost 1 second was the weighted
average for a single TCP Packet to be ACKed).  Other connections did
not perform this well. The technical term I use for this problem is
the network was "Sucking Wind" //:~).  (I am not sure you will find
this definition in the COMER or STEVENS TCP reference books but maybe
in their next Edition).

Protocols which include "heavy" network overhead like Web Console and
Telnet (the heavy overhead in telnet is specific to it's inbound single
character echo) did not stay connected to the network.  I saw the same
problems connecting with WRQ Telnet from my NT to my HP-UX machines on
the same network as my HP e-3k systems.

I was successful with NS-VT WRQ connections from my NT to the HP e-3k
and WRQ FTP connections from my NT to the HP e-3k after I tuned my TCP
timers to "WORK AROUND" the network traffic saturation problem:

[1  ]     Retransmission Interval Lower Bound (Secs)
[180  ]   Maximum Time to Wait For Remote Response (Sec)
[2  ]     Initial Retransmission Interval (Secs)
[6  ]     Maximum Retransmissions per Packet

I increased the "Maximum Retransmissions per Packet" from 5 to 6 and I
was able to achieve a stable (but poor performing) NS-VT VTSERVER
connection from my NT machine to my HP e-3k while my PC was infected
(heavy broadcasting over a relatively slow performing ISDN link).  I
saw no problems with FTP transfers after this timer change.

I hope this helps.

P.S. Keep in mind the "Secure Web Console" does not use the HP e-3k TCP
Stack.  The "Secure Web Console" connects to the HP e-3k with a RS232
asynchronous cable

Regards,

James Hofmeister
Hewlett Packard
Worldwide Technology Network Expert Center
P.S. My Ideals are my own, not necessarily my employers.

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