Neither of these processors will work on ethernet right out of the box. You will have to go with a 5/05 for ethernet use. For software we use AB. It is quite expensive and is labeled RSLogix500. It will also work with the micrologic processor. You will also have to have a cable which is a serial link. If you use the 5/05 you will still need to communicate serially to add the IP address. Once it is in you can go ethernet. These are good processors and most last for years. Unfortunately AB is unsympathetic to us hobbiest when it comes to software since they are designed for industrial use. The software comes on cd but is unusable until the key is downloaded from a floppy. You can run without downloading but you will have to insert the floppy each time you boot up. I believe AB does make a ethernet card which will work with the 5/04 but I have not used it. I would suggest you contact your local AB dealer. Most of them have a service tech that can help.