Using the SMS version of Network Monitor.......t gives counts for packets sent, broadcasts, and collisions (resends). Very good product although I
have nothing to compare it to........captures all traffic across the wire and if you know how to read, very useful.

Dave

DAVCO Automation
"The Developing Automation Value Company"

 

It's like an oscilloscope for protocols. Check out http://www.ethereal.com for an open source network monitor.

Dan Hazel
Rockwell Automation

 

Besides, how did you detect the collisions, by missing packages of by something saying that there was a collision?


/Johan Bengtsson

----------------------------------------
P&L, Innovation in training
Box 252, S-281 23 H{ssleholm SWEDEN
Tel: +46 451 49 460, Fax: +46 451 89 833
E-mail: [email protected]
Internet: http://www.pol.se/
----------------------------------------

 

Using the SMS version of Network Monitor.......it gives counts for packets sent, broadcasts, and collisions (resends). Very good product although I
have nothing to compare it to........captures all traffic across the wire and if you know how to read, very useful.

Dave

DAVCO Automation
"The Developing Automation Value Company"


> Besides, how did you detect the collisions, by missing packages
> of by something saying that there was a collision?

 

Ah, I don't think "resend" equals "collision".
A collision requires a resend, but there are other reasons too.


/Johan Bengtsson

----------------------------------------
P&L, Innovation in training
Box 252, S-281 23 H{ssleholm SWEDEN
Tel: +46 451 49 460, Fax: +46 451 89 833
E-mail: [email protected]
Internet: http://www.pol.se/
----------------------------------------

 

I've used both ControlNet and Ethernet/IP with ControlLogix. I am completely indifferent about either of them, but when pressed I will chose ControlNet because of noise immunity. ControlNet cable is harder to work with, and you need RSNetworx (or the equivalent if you're talking about non-AB stuff). Ethernet/IP does NOT need an equivalent to RSNetworx, which is great, but while the cable is easy to work with RJ-45 connectors kinda suck for the shop floor. In terms of performance, I don't see a difference.

I've also used Modbus/TCP a little bit. Again, there are ups and downs. Again, no real performance difference. The only thing I can say is look at what you need to talk to and decide based on the vendors you are comfortable with. Obviously there is no point in try to do Modbus/TCP on an A-B system when Ethernet/IP is handled natively.

-James Ingraham
Sage Automtion, Inc.

 

And I'm sure if large volume multicasts (like FF/HSE, Ethernet/IP, or FDDS) cause problems in current technology switches, it's "just silicon" to make switches smart enough to understand IGMP messages and start supporting intelligent multi-cast filtering.

Regards

Best Regards

Lynn August Linse, [email protected]
3 Rue Monet, Foothill Ranch CA 92610
Ph: 949-300-6337 Fx: 612-677-3253

 

I have installed quite a few very large systems and I know this from practical knowledge:

Install Cat5e cable at the minimum (use a cable scanner to verify). Run both ends Host and Switch in full duplex (easily verified by the
Switch. Cable and infrastructure (like Power, UPS) is 50% of networking. Segmenting your network for max pipe control is the next step.
There are reasons to run lots of protocols, and directory services, etc. but MOST folks don't need them. Run it simple and strong. If you
can afford it, nake you Gig Fiber or Copper ports full duplex. Settle for noting less than full duplex - collision and congestion go away
for the most part.