![]() A mass of support electronics is embedded in the controller chip to drive the LED. The LED is connected to the output of a specialised Ethernet controller chip. The LED on a network port is at Layer 2 (Data Link). Above 10Mbps, the influence of the LEDs and transistors starts to interfere and the test circuit actually creates the fault. It is not very useful though, as it only indicates electrical activity. If you drop down to 10-BaseT (10Mbps) it is fairly easy to drive an LED directly from the wire, at Layer 1 (Physical), with a couple transistors. The very first question you need to ask yourself is, what layer do I need to decode? Go look at the OSI model as a starting point. Connecting 'billions' of devices is never going to be a case of 'just.' It's bloody complicated stuff! TCP/IP is a layered protocol 'stack' approximating the OSI 7 layer conceptual model. The device you want to test sends data over TCP/IP - A protocol that, as I speak, is allowing several billion computers to talk to each other. Thanks again, DanĬonsidering the questions you are asking, I am not so sure you do understand. As silly as it may sound, there are LED's on every network card that signify data travel, so couldn't something very basic be made that would simply light up to let me know of a successful data push?.literally it would be a good start to atleast letting me know my data port output is still alive. I would not be joining their network, I would just be unplugging my device from them, then trying to see if data is being sent when my instrument gets a good reading. Thanks for the great info, I understand the need for a PC to interpret the message, and the issues around connecting. Wireshark or even tcpdump are fine programs, but they're big by "handheld" standards. Actually analyzing packets is much more complicated than dumping serial data.The existing ethernet shields couldn't even sustain 10Mb/s. (close to 1Gb/s) PC-class hardware can do it these days, but an arduino-class box is pretty useless. Once you've achieved that physical connection, you need an ethernet device to do the actual "sniffing" it needs to be able to work in "promiscuous" mode (receives packets destined for any ethernet address), and it needs to be able to handle the sort of data rates that exist on the network.(1) and (2) can be addressed by using a product that "taps" the connection between the target and the switch essentially a 3-port "hub" For example ($70 !).Except that switch ports are mostly SWITCHED these days, which means that packets not destined for a particular host don't show up on the other ports of the switch at all.Normaly, you'd plug into another switch port. You can't easily tap in to an ethernet connected electrically the signalling is much more complicated than a serial port.There are several problems trying to do this sort of thing: They key here is I need to have other people use this device as well, and they will not even be at my level, so quick an easy it must be.Thanks again. I appreciate ANY help here, and even though I have no Arduino experience, I can learn. If it could see the string data, that would be great, if I can just verify that a packet has been sent ( size would be cool) with an LED even, that would be atleast something to get me to the next step in troubleshooting a comm problem. I have issues bringing laptops into customer sites due to security reasons they implement, as well as it's usually that I am in an area where a laptop may get very dirty, burnt or dropped while I check systems ( think steel mill here). What I am asking for is something just as easy and quick to see my data string on the TCP/IP connection we now use more frequently. I have many machines that still use rs232, and for sniffing those serial ports I use a "DATABOY"(gameboy with a card made for sniffing) which is super fast and easy to use. We then calculate data and send it to modelling software that allows for chemistry changes in the process for customer requirements. I troubleshoot my companies' equipment that measures motlen metal via various thermocouples. Hello, I am reaching out for a bit of assistance here, and appreciate any feedback.
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