An apparatus which establishes an electrical feedthrough for a substrate, such as a housing wall of a data storage device enclosure. The rails have adjacent rail ends separated and thereby forming a gap. The ports are provided for sending and receiving frames. In addition, the first user selectively specifies which historical purchase information may be viewed by the second customer. The controller upon attachment to the network registers itself and notifies the plurality of clients. The method can further include removing an oldest request from the pending requests and adding the first request to the pending requests, and processing a newest request in the pending requests by sending a message to the second device and receiving the physical address responsive to the message.