A software network bridge is disclosed which allows the connected network segments to be presented as a single network unit to the host computer. The software bridge can be implemented as an intermediate network driver, abstracting multiple network segments into a single network interface for higher level protocols and applications. While the intermediate network driver acts as a software bridge implementing the Spanning Tree Algorithm, it also acts a network interface driver to higher level protocols, conglomerating information from the multiple underlying network interface cards and forwarding along commands from the higher level software to the appropriate network interface card. The intermediate network driver can also simultaneously send the same data packet through multiple network interfaces by creating multiple packet descriptors, each pointing to the same data, but each given individually to the underlying network interfaces to control during their transmission. Further efficiencies can also be achieved by the software bridge, implemented as an intermediate network driver, through the use of a dynamic allocation scheme which increases the size of the useable buffers of each network interface without increasing the overall memory consumption, and the use of a queuing scheme which preliminarily examines incoming data packets to determine if any processing needs to be performed, and queues the packets should they require processing. Additionally, a user interface is presented exposing this functionality of the intermediate network driver.