Role of VND for designing of an infrastructure based software defined network Software Defined Network (SDN) has the ability to separate data plane from the control plane in a network. Visual Network Description (VND) is a GUI tool which helps to develop this network manually while simulation. With this tool, one can manually setup the required components in SDN and can define the properties of different links, switches and controllers attached with it for simulating this network through Mininet. VND automatically generates python script compatible for simulation on Mininet for this manually defined network. The work in this paper discusses about the role of VND while simulation of infrastructure based Software Defined Network using mininet.