We discussed this briefly today. The idea we're thinking about currently is adding a NetworkProtocol resource subordinate to each EthernetInterface. This will allow you to control a protocol on an interface by interface basis. However, we think there may be some complexities with going this route, mainly what is client software supposed to do if it finds a NetworkProtocol resource subordinate to a given Manager in addition to NetworkProtocol resources subordinate to each interface. What's your opinion on this type of approach?