For many smaller and larger entities over the last couple of decades, information systems and technologies have become an integral part of their operations and played a major role in drastically changing and often improving their business processes. As computers become more and more integrated into our business organizations, we end up leaving and storing confidential, vital business and sensitive information on them. In general, larger organizations have the technical expertise and resources to better secure computing services. The Small to Medium Enterprises (SMEâs), however, often lack the platforms, infrastructure, technical expertise, and the required financial resources to be able to utilize modern secure technologies for computing services. This paper discussed the importance of network security, analyzed different type of threats to network infrastructure, different methodologies that can be used to mitigate network infrastructure threats and have proposed an approach for securing SMEâs network infrastructure. This approach suggested Unified Threat Management (UTM) as the first line of protection to the network, based on the links between each distribution switch layers which offers a zone based monitoring and controlling system to prevent the network from any possible threats.