A data frame transmitted over a serial link between a destination network and a source network is received by a computer-implemented system in the destination network. The data frame is compatible with a data link layer protocol and includes a data field. The computer-implemented system in the destination network converts the data frame directly into a format compatible with an application layer protocol, where converting the data frame into the format comprises interpreting received information included in the data field as numerical values rather than executable code. The computer-implemented system in the destination network outputs the numerical values to an application in the destination network.