Embedded Ethernet and Corporate LAN
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Embedded Ethernet and Corporate LAN

 
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TECH_NEWS
Guest





Posted: Fri May 27, 2005 7:58 am    Post subject: Embedded Ethernet and Corporate LAN Reply with quote

We have an embedded system, that has a SMSC 91C111 Ethernet Chip, ARM
Processor, and Windows CE 3.0. Our system works great when not exposed to a
"Corporate Ethernet" environment. When we put our system on a DSL line, it
works great. We get massive buffer overflows on a typical LAN network.
I have been looking for others who have embedded products, that have similar
experiences. Does anyone develop embedded products, that go onto LAN
environments? What did you do to reduce "House Keeping" signals (DHCP
OFFERS, ARP REQUESTS, DNS, NETBIOS BROADCASTS)?

Sorry if this is the incorrect group for this question, but found it on
embedded.com website.

Thank you
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glen herrmannsfeldt
Guest





Posted: Fri May 27, 2005 1:26 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

TECH_NEWS wrote:

Quote:
We have an embedded system, that has a SMSC 91C111 Ethernet Chip, ARM
Processor, and Windows CE 3.0. Our system works great when not exposed to a
"Corporate Ethernet" environment. When we put our system on a DSL line, it
works great. We get massive buffer overflows on a typical LAN network.
I have been looking for others who have embedded products, that have similar
experiences. Does anyone develop embedded products, that go onto LAN
environments? What did you do to reduce "House Keeping" signals (DHCP
OFFERS, ARP REQUESTS, DNS, NETBIOS BROADCASTS)?

Unlike many posts here, this is probably the right group.

I would guess that the problem is broadcasts. The broadcast traffic
level can get pretty high on some networks, and every one of those
has to have at least some processing done on it. You have to minimize
that processing time, especially for packets that you don't need.

Unless you are a DHCP server, you should be able to ignore broadcast
DHCP, and maybe all broadcast IP. The one you can't ignore is ARP,
so you need to quickly detect if the ARP is for you, and ignore it
if it isn't. You didn't say you were doing IP, but in any case you
have to identify the TYPE field as soon as possible, and flush it
if it is the wrong type as fast as possible.

-- glen
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Guest






Posted: Fri May 27, 2005 2:21 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

I see this from time to time
with commercial network equipment.

A fix that I have been able to use is to
block unwanted traffic. Typically network
equipment does not need to receive IP
broadcasts. Blocking IP broadcasts
still allows ARP to operate.

Other than that you will need to make your
code more efficient at rejecting unwanted
traffic. This is in effect the same thing as I
have already said I guess.
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Guest






Posted: Fri May 27, 2005 4:20 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

Quotes vanished! - see later

10M is a fine idea.

I use Google Groups for news and I suspect that it
now does all sorts of weird things. I have been too
lazy to try to figure out what it is doing. The editor
presents in HTTP with proportional fonts for example.

The default view of messages has quotes
folded into a link, I don't know if these are
quotes explicitly in the message
of if they are "helpful" links to the
message actually responded to.

I had suspected that my netiquette was slipping
but with the massaged google view that I
get it is quite hard to figure out what is going on.

I will have a look and comment to google
if applicable but I hold out little hope
that they will change anything.

'tis the way of the world it seems -- magic fixups everywhere
Back to top
Al Dykes
Guest





Posted: Fri May 27, 2005 4:20 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

In article <1117185681.473665.251460@f14g2000cwb.googlegroups.com>,
<anybody43@hotmail.com> wrote:
Quote:
I see this from time to time
with commercial network equipment.

A fix that I have been able to use is to
block unwanted traffic. Typically network
equipment does not need to receive IP
broadcasts. Blocking IP broadcasts
still allows ARP to operate.

Other than that you will need to make your
code more efficient at rejecting unwanted
traffic. This is in effect the same thing as I
have already said I guess.



(please don't trim the quote from the message the next time. thanks.)

If CE will let you try setting the properties on the NIC to 10MB/half
duplex.


--
a d y k e s @ p a n i x . c o m

Don't blame me. I voted for Gore.
Back to top
Hansang Bae
Guest





Posted: Sun May 29, 2005 5:52 am    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

anybody43@hotmail.com wrote:
[snip]
Quote:
I use Google Groups for news and I suspect that it
now does all sorts of weird things. [snip]


Ever since my shell account was revoked (years ago), I've been on a
constant search for a decent newsreader. Xnews, was OK. Gravity was
pretty decent. Agent was semi-OK. Then I found XanaNews. Perfect
news reader for me! For those using Windows, it's definitely worth a
look.


--

hsb


"Somehow I imagined this experience would be more rewarding" Calvin
**************************ROT13 MY ADDRESS*************************
Due to the volume of email that I receive, I may not not be able to
reply to emails sent to my account. Please post a followup instead.
********************************************************************
Back to top
Al Dykes
Guest





Posted: Sun May 29, 2005 8:07 am    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

In article <Ym8me.654$jU5.877788@twister.nyc.rr.com>,
Hansang Bae <uonr@alp.ee.pbz> wrote:
Quote:
anybody43@hotmail.com wrote:
[snip]
I use Google Groups for news and I suspect that it
now does all sorts of weird things. [snip]


Ever since my shell account was revoked (years ago), I've been on a
constant search for a decent newsreader. Xnews, was OK. Gravity was
pretty decent. Agent was semi-OK. Then I found XanaNews. Perfect
news reader for me! For those using Windows, it's definitely worth a
look.


--

hsb


My ISP will sell you a shell account on a fully configured unix
machine for $10/mo with 50MB of disk space and a personal web server
included.

Panix.com.

One of the oldest internet-connected services.

I have no relationship to Panix other than being a satisfied customer
for almost 15 years. I've used trn for my news reader ever since then
and I can't imagine having to use a GUI news reader.
--
a d y k e s @ p a n i x . c o m

Don't blame me. I voted for Gore.
Back to top
Guest






Posted: Mon May 30, 2005 4:20 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

Quote:
a d y k e s @ p a n i x . c o m
Hansang Bae <u...@alp.ee.pbz> wrote:
anybod...@hotmail.com wrote:
[snip]
I use Google Groups for news and I suspect that it
now does all sorts of weird things. [snip]
pretty decent. Agent was semi-OK. Then I found XanaNews. Perfect
news reader for me! For those using Windows, it's definitely worth a
look.
My ISP will sell you a shell account on a fully configured unix
machine for $10/mo with 50MB of disk space and a personal web server
included.

Warning - Way off topic. (And longish now too).

I hope you like the hand quoted message _a lot_:-)

To use XanaNews or similar I guess that I would need a
newsfeed from somewhere, somewhere to store it, and then
I would not be able to access it other than from somewhere
with access to my home network. Can you suggest a free
newsfeed?

Google groups are somewhat convenient for me but clearly
if the sent messages are causing problems that
that is something to consider.

I would not now consider using anything other than a
GUI for interactive work:) It is not necessary to have
a bit mapped display though. I have used very satisfactory
Windows-pointer-mouse-menus interfaces that
were based on character mode displays. e.g.
Turbo Pascal (V4 or later IIRC), or Turbo Debugger.
The latter being my candidate for the best software
ever created considering the complexity of the task
(machine code symbolic debugger) and the ease of use
of the software. I can't recall ever needing the manual once
the thing was loaded and running in the desired mode.
(Hobby use only)
In comparison I couldn't use MS Codeview without
applying both hands to the manual and being restricted to
typing with my elbows and nose.

Since the man who I believe did it is the .NET development
tool architect I would guess that the new MS stuff is
top notch too.
His name is I suspect Anders Hejlsberg.

Amazingly enough, well it is to me, Xananews is written
with Delphi which is the successor to Turbo Pascal.
Back to top
Hansang Bae
Guest





Posted: Tue May 31, 2005 8:20 am    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

anybody43@hotmail.com wrote:
[snip]
Quote:
were based on character mode displays. e.g.
Turbo Pascal (V4 or later IIRC), or Turbo Debugger.
The latter being my candidate for the best software
ever created considering the complexity of the task
(machine code symbolic debugger) and the ease of use
of the software.
[snip]
Amazingly enough, well it is to me, Xananews is written
with Delphi which is the successor to Turbo Pascal.

I still remember the day I took the shrink wrap off of Turbo Pascal
from Borland. I loaded it up on my 286-16 Austin computer and was
BLOWN away. Up until then, I only had rudimentary tools available on
VAX compilers. I once had to cycling through my program on a piece of
paper to catch a "off by one error" problem.

It truly was a nice piece of work! There are very few things I
consider a "true classic." Turbo Pascal is one of those. My HP-41CV
was another classic. Man I loved that calculator. My buddy still has
one and I considered whacking him just to get my hands on that
calculator! :)


--

hsb


"Somehow I imagined this experience would be more rewarding" Calvin
**************************ROT13 MY ADDRESS*************************
Due to the volume of email that I receive, I may not not be able to
reply to emails sent to my account. Please post a followup instead.
********************************************************************
Back to top
James Knott
Guest





Posted: Tue May 31, 2005 4:20 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

Hansang Bae wrote:

Quote:
I still remember the day I took the shrink wrap off of Turbo Pascal
from Borland. I loaded it up on my 286-16 Austin computer and was
BLOWN away. Up until then, I only had rudimentary tools available on
VAX compilers. I once had to cycling through my program on a piece of
paper to catch a "off by one error" problem.


Many years ago, I was using Turbo C++ in a class I was attending and used
Borland C++ for OS/2, at home. Worked great, though I had to worry about
minor details such as integer sizes, when moving between the two. I also
used to do my Fortran homework on a VAX 11/780.
Back to top
J. Clarke
Guest





Posted: Thu Jun 02, 2005 12:20 am    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

anybody43@hotmail.com wrote:

Quote:
a d y k e s @ p a n i x . c o m
Hansang Bae <u...@alp.ee.pbz> wrote:
anybod...@hotmail.com wrote:
[snip]
I use Google Groups for news and I suspect that it
now does all sorts of weird things. [snip]
pretty decent. Agent was semi-OK. Then I found XanaNews. Perfect
news reader for me! For those using Windows, it's definitely worth a
look.
My ISP will sell you a shell account on a fully configured unix
machine for $10/mo with 50MB of disk space and a personal web server
included.

Warning - Way off topic. (And longish now too).

I hope you like the hand quoted message _a lot_:-)

To use XanaNews or similar I guess that I would need a
newsfeed from somewhere, somewhere to store it, and then
I would not be able to access it other than from somewhere
with access to my home network. Can you suggest a free
newsfeed?

You don't need a news _feed_, you need a news _provider_--a news _feed_ is
what the providers get and it's expensive--to use a feed you need to be
running your own news _server_, not a _client_ like Xananews.

One provider that seems to be decent and is free is
<http://news.sunsite.dk>. <http://news.individual.net> used to be free and
is now ten Euros a year, whatever that works out to in dollars, which seems
pretty reasonable to me.

Your ISP may also have a news server--most used to but some are
discontinuing service.

Google Groups used to be an archive--it is _not_ how most USENET users
access USENET.

You should be able to access your USENET provider from anywhere, not just
your home network. If it's an ISP server then you'd probably have to be
logged into that ISP's service, if it's a third party server like
news.sunsite.dk or news.individual.net then you can access it from any
Internet connection that doesn't have NNTP or the specific addresses
blocked.

Quote:
Google groups are somewhat convenient for me but clearly
if the sent messages are causing problems that
that is something to consider.

I would not now consider using anything other than a
GUI for interactive work:) It is not necessary to have
a bit mapped display though. I have used very satisfactory
Windows-pointer-mouse-menus interfaces that
were based on character mode displays. e.g.
Turbo Pascal (V4 or later IIRC), or Turbo Debugger.
The latter being my candidate for the best software
ever created considering the complexity of the task
(machine code symbolic debugger) and the ease of use
of the software. I can't recall ever needing the manual once
the thing was loaded and running in the desired mode.
(Hobby use only)
In comparison I couldn't use MS Codeview without
applying both hands to the manual and being restricted to
typing with my elbows and nose.

Since the man who I believe did it is the .NET development
tool architect I would guess that the new MS stuff is
top notch too.
His name is I suspect Anders Hejlsberg.

Amazingly enough, well it is to me, Xananews is written
with Delphi which is the successor to Turbo Pascal.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Back to top
Guest






Posted: Mon Jun 27, 2005 4:20 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

Off Topic - Google Groups

CBFalconer <cbfalco...@yahoo.com>
Says:

"If you want to post a followup via groups.google.com, don't use
the broken "Reply" link at the bottom of the article. Click on
"show options" at the top of the article, then click on the
"Reply" at the bottom of the article headers." - Keith Thompson

Thanks everyone for pointing out my errors
and especially for the suggestions.
Back to top
stefano.lena
Guest





Posted: Tue Aug 30, 2005 2:35 pm    Post subject: Re: Embedded Ethernet and Corporate LAN Reply with quote

Hi,

what about your SMSC 91C111 driver for Windows ce on ARM board?
Did you write it or find it somewhere?
I'm looking for one, free or commercial.
Could you please send me some information?

Regards

Lena

-------------------------------------
glen herrmannsfeldt wrote:

Quote:
TECH_NEWS wrote:

We have an embedded system, that has a SMSC 91C111 Ethernet Chip,
ARM
Processor, and Windows CE 3.0. Our system works great when not
exposed to a
"Corporate Ethernet" environment. When we put our
system on a DSL line, it
works great. We get massive buffer overflows on a typical LAN
network.
I have been looking for others who have embedded products, that
have similar
experiences. Does anyone develop embedded products, that go onto
LAN
environments? What did you do to reduce "House Keeping"
signals (DHCP
OFFERS, ARP REQUESTS, DNS, NETBIOS BROADCASTS)?

Unlike many posts here, this is probably the right group.

I would guess that the problem is broadcasts. The broadcast traffic
level can get pretty high on some networks, and every one of those
has to have at least some processing done on it. You have to minimize
that processing time, especially for packets that you don't need.

Unless you are a DHCP server, you should be able to ignore broadcast
DHCP, and maybe all broadcast IP. The one you can't ignore is ARP,
so you need to quickly detect if the ARP is for you, and ignore it
if it isn't. You didn't say you were doing IP, but in any case you
have to identify the TYPE field as soon as possible, and flush it
if it is the wrong type as fast as possible.

-- glen







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