Network Security Issues of Data Link Layer: An Overview

There is a cardinal infrastructure of application software's, protocols, and physical devices over different sort of wired and wireless networks, that need to communicate with each other, whether located not only on earth but also in the space. OSI seven-layers model has become an international standard to communicate securely and confidently among different kinds of the corporate networks while keeping the other OSI layers unfamiliar with the current layer of communication. This secrecy among the layers results in vulnerability to attack in a way that if one layer is compromised to attack, the other layers will not be able to detect it properly. This individuality of OSI layers makes the whole network severely vulnerable to attack particularly due to the data link layer as compared to other layers. Generally network security problems at layer 2 are not properly addressed as compared to other layers, rather the people focus on the device's security for the whole management system instead. This paper encompasses network security problems faced due to lack of hardening the layer 2 and it also describes, how it makes a LAN or the system of networks more vulnerable to attacks, especially for the MAC flooding, ARP spoofing, VLAN hopping, DHCP attacks, Denial-of-Service (DoS) and Spanning Tree Protocol in a very concise manner.