Data Link Layer-Security Issues A Annapurna, M. Tech, Assistant Professor, CSE Department Vardhaman College of Engineering Hyderabad,India e-mai:purna.1201@gmail.com Sheena Mohammed, M.Tech, Assistant Professor, CSE Department Vardhaman College of Engineering Hyderabad,India e-mail:sheenamd786@gmail.com D.Madhuri, M.S Assistant Professor, CSE Department Vardhaman College of Engineering Hyderabad,India e-mail:madhuriqa123@gmail.com Abstract-Security issues in the data link layer are not properly explained while network security problems in other layers of OSI model are studied and addressed. In this paper, we propose a new security inter-layering structure to secure data link layer in Internet protocol over Ethernet networks. In the data link layer, we have proposed to use secure namespaces instead of Media Access Control(MAC) to identify network devices, which provides a mean to bind data link layer with other layers of OSI model very securely. Present network structure provides a link to link security and the key establishment protocol to generate security parameters in this layer. Keyword- MAC, OSI, IEEE802.1 I. INTRODUCTION Data link layer is one of the layers in OSI model which deals with raw data transmission from data link layer to network layer. Data transmitted over the network is done through fragmenting the data into small packets. The function of data link layer is to provide service to network layer. Figure 1. OSI Model Security issues in this layer of local area networks have started long term overdue in standard groups and in the literature. Security in wireless networks have been greatly improved by IEEE 802.11i standards. Confidentiality, integrity and authenticity attacks exist in both wired and wireless networks. Security issues in wired LANS need to be addressed to improve security in both networks. In this paper, we propose a new data link layer security architecture with a key establishment protocol that may be incorporated into MAC security. In LANs, we observe that several security threats are caused by the insecure addressing in the data link layer and the weak link between the network and data link layers. Layers lack the ability to inform other layers whether any security measures are utilized or security weaknesses exist. In this paper, we examine the data link A Annapurna et al./ International Journal of Computer Science & Engineering Technology (IJCSET) ISSN : 2229-3345 Vol. 4 No. 07 Jul 2013 1009