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Nowadays, LTE (Long Term Evolution) is widely used. The MAC layer plays an important role in the quality of LTE transmission. Spectrum efficiency, frame loss rate, throughput and delay are selected as the primary evaluation criterion of the performance of LTE system. This paper deals with the performance of MAC layer in the LTE networks. The system-level performance analysis of MAC layer is conducted through the Network Simulator 3. An orthogonal experimental design is adopted to evaluate the effect of various key factors on the MAC performance of LTE network. These factors mainly include the bandwidth, MAC layer scheduling algorithm, customer density, partial OFDM algorithm and other factors. We also look for a reasonable LTE communication scheme for different conditions to make sure that the system has good performance such as a higher throughput, a smaller end-to-end delay, a smaller delay jitter and a lower frame loss rate.

Authenticating wireless devices based on PARADIS technique draws increasing research interest recently, providing security access services in wireless networks. This paper provides an overview of various schemes for PARADIS identification using physical layer characteristics. Firstly, this work systematizes the existing knowledge on this topic for a better understanding of PARADIS device identification, its implications on the analysis and design of security solutions in wireless mobile networks, and possible applications. Secondly, we review the development progress of PARADIS identification techniques, discuss the merits and demerits of existing PARADIS identification schemes and provide a summary of the current state of the art. Moreover, we propose a new authentication scheme based on PRARDIS and discuss its security and feasibility in the SAE/LTE application. We also highlight the open problems of PRARDIS and motivate future works.

In a freeway vehicular ad hoc network (VANET) environment, an efficient ad hoc routing protocol plays a very important role to enhance the safety of passengers. This paper presents the latest result of simulation model of three mobile ad hoc routing protocols: destination-sequenced distance-vector protocol (DSDV), dynamic source routing (DSR) and ad hoc on-demand distance vector (AODV). The performance of three protocols under constant bit rate traffic is evaluated and compared with five quality indices. The simulation results show that both the reactive routing protocols, DSR and AODV, have better performance than the proactive routing protocol DSDV. DSDV has largest packet loss rate and smallest system throughput among the three protocols. This paper also shows that the effect of varying mobility has undeniably influenced the performance of both reactive routing protocols. DSR is better in the protocol overhead than AODV. However, there is critical jitter variation in the DSR. As a whole, AODV is more appropriate than DSR for the freeway VANET.

A new routing algorithm applicable for client network of Wireless Mesh Network (WMN), called hybrid maintenance routing (HMR), is presented. WMN share common features with ad hoc networks, the routing protocols developed for ad hoc networks can be applied to WMN. Based on DSR (dynamic source routing), HMR applies multi-path routing to improve the routing fault tolerance of client networks of WMN. Route maintenance has been the main area of protocol in ad hoc network. There are two kinds of approach for route maintenance, the proactive routing maintenance and the on-demand reactive routing maintenance. A hybrid maintenance approach which combines the proactive routing maintenance and the reactive routing maintenance will improve the validity of multi-path without increasing too much overhead.

SSL (secure sockets layer) protocol is one of key technologies to keep userpsilas data in secure transmission via Internet. This paper is present to analyze the security of SSL protocol and propose a new scheme of SSL protocol configured in the Linux operating system (OS). The experimental results show that the proposed scheme is feasible and practical as a secure solution for Web-based communication, and the SSL protocol is compatible to the other protocol in application layer via proper configuration.