Methods and a device for changing the message size broadcast over a network and furthermore preventing fragmentation in networks are provided. The device intercepts a message transported across a network, wherein the message is sent from a data source to a data receiver and changes the message size. In addition, the device may use the methods to change the message size of data transmitted over a network thus reducing fragmentation. As a result, network devices such as classifiers preferably avoid re-assembling fragments. More specifically by reducing re-assembling, network devices like a classifier can react more quickly to applications requiring information found in both of an IP and TCP/UDP header.