Qianbin Chen

Computation Offloading and Resource Allocation in Wireless Cellular Networks With Mobile Edge Computing

Mobile edge computing has risen as a promising technology for augmenting the computational capabilities of mobile devices. Meanwhile, in-network caching has become a natural trend of the solution of handling exponentially increasing Internet traffic. The important issues in these two networking paradigms are computation offloading and content caching strategies, respectively. In order to jointly tackle these issues in wireless cellular networks with mobile edge computing, we formulate the computation offloading decision, resource allocation and content caching strategy as an optimization problem, considering the total revenue of the network. Furthermore, we transform the original problem into a convex problem and then decompose it in order to solve it in a distributed and efficient way. Finally, with recent advances in distributed convex optimization, we develop an alternating direction method of multipliers-based algorithm to solve the optimization problem. The effectiveness of the proposed scheme is demonstrated by simulation results with different system parameters.

Joint Computation Offloading and Interference Management in Wireless Cellular Networks with Mobile Edge Computing

Mobile edge computing (MEC) has attracted great interests as a promising approach to augment computational capabilities of mobile devices. An important issue in the MEC paradigm is computation offloading. In this paper, we propose an integrated framework for computation offloading and interference management in wireless cellular networks with MEC. In this integrated framework, we formulate the computation offloading decision, physical resource block (PRB) allocation, and MEC computation resource allocation as optimization problems. The MEC server makes the offloading decision according to the local computation overhead estimated by all user equipments (UEs) and the offloading overhead estimated by the MEC server itself. Then, the MEC server performs the PRB allocation using the graph coloring method. The outcomes of the offloading decision and PRB allocation are then used to distribute the computation resource of the MEC server to the UEs. Simulation results are presented to show the effectiveness of the proposed scheme with different system parameters.

Grid-based directed diffusion for wireless sensor networks

In this paper, we propose a grid-based directed diffusion (GDD) to save the energy of nodes in wireless sensor networks. Based on virtual grids which are set up according to routing fidelity, small clusters are formed. In GDD, the flooding of sensed data is limited in .clusters, which can save energy and decrease delay.

Modeling and simulation of fading, pathloss, and shadowing in wireless networks

To explore and simulate the influence of multipath fading, pathloss, and shadowing fading on wireless networks, this paper creates mathematical and simulation models for multipath fading and shadowing fading, designs an approach to calculating the shadowing effect, and optimizes the utilization of the pathloss exponent. Moreover, modeling and simulation are implemented with a simulation software-OPNET for demonstrating the above work. Simulation results quantitatively show the impact of these effects on throughputs and communication ranges of IEEE802.11a/b/g wireless networks. These results are consistent with present documents and theoretical analysis, thus simulation of wireless networks become more accurate and reasonable. Simultaneously, the simulation platform used in our research is also improved by integrating new models.

Integration of Networking, Caching, and Computing in Wireless Systems: A Survey, Some Research Issues, and Challenges

Since the recently emerging mobile applications have posed significant demands not only on high data rate but also on high caching and computing capabilities, the growth in communication capability alone is no longer sustainable for wireless networks. The integration of networking, caching, and computing functionalities into one system can provide not only native support for highly scalable and efficient content retrieval, but also powerful capability of data processing, hence reducing duplicate content transmissions and enabling swift executions of computationally intensive tasks. Despite the prospect of integrated networking, caching, and computing systems, a number of significant research challenges remain to be addressed prior to widespread deployment of integrated networking, caching, and computing systems, including latency requirement, interfaces, mobility management, resource and architecture tradeoffs, convergence, etc. In this paper, we provide a brief survey on some of the works that have been done to enable the integrated networking, caching, and computing system, and discuss several research challenges. We identify a number of important aspects of the integration of networking, caching, and computing: motivations, frameworks, performance metrics, enabling technologies, and challenges. At last, some broader perspectives are explored.

Network-based mobility management for LISP network

Recently, Locator Identifier Separation Protocol (LISP) has been proposed as an efficient approach for dealing with the problem of scalable Internet routing. To support mobility management in LISP network, the host-based mobility management schemes, such as MIP, can be applied. However, the host-based scheme poses additional functional requirements on mobile node (MN), which is highly undesired for practical application. Furthermore, the complicated binding update process of MIP results in relatively large signaling cost and long handoff latency, making the seamless handoff of MNs impermissible. In this paper, the mobility scenario in LISP network is analyzed in detail and a network-based mobility management scheme is proposed for LISP network, which supports mobility transparency and handoff process simplification. The numerical results demonstrate that the proposed scheme offers better handoff performance comparing to the MIP-based scheme.

An optimal back-off parameters study for multi-channel MAC protocols in VANETs

Delay and reliability sensitive safety messages and throughput sensitive non-safety messages are transmitted in VANETs. Throughput and delay are always opposed in wireless networks, so it is necessary to reach the optimum point between these two parameters in many cases. This paper presents an optimization method of the back-off parameters in multi-priority supported multi-channel MAC protocol in VANETs to solve this problem. This method calculates throughput and delay of the network, then determines the optimum transmitting probabilities of the two classes of messages by an optimization model. Then the optimum back-off parameters can be calculated according to the transmitting probabilities. Simulation results show that this method can achieve the aim and remain stable.

Supporting Service Differentiation and Maximizing System Saturation Throughput: A Contradictory in IEEE 802.11e WLAN

While most existing work focuses separately on how to improve WLAN saturation throughout and how to provide differentiated service, few attention is put to study their relationship. In this paper, we investigate the impact of service differentiation on saturation throughput maximization in IEEE 802.11e WLANs and theoretically prove that it is contradictory and impossible to achieve both of them simultaneously. In other words, saturation throughput is maximized without service differentiation or service differentiation reduces the maximal achievable saturation throughput more or less.

Joint computation and radio resource management for cellular networks with mobile edge computing

Mobile edge computing (MEC) has attracted great interests as a promising approach to augment computational capabilities of mobile devices. An important issue in the MEC paradigm is computation offloading. In this paper, we propose an integrated framework for computation offloading and interference management in wireless cellular networks with mobile edge computing. In this integrated framework, the MEC server makes the offloading decision according to the local computation overhead estimated by all user equipments (UEs) and the offloading overhead estimated by the MEC server itself. Then, the MEC server performs the PRB allocation using graph coloring. The outcomes of the offloading decision and PRB allocation are then used to allocate the computation resource of the MEC server to the UEs. Simulation results are presented to show the effectiveness of the proposed scheme with different system parameters.

Algebraic and linear programming decoding of the (73, 37, 13) quadratic residue code

In this paper1, a method to search the subsets I and J needed in computing the unknown syndromes for the (73, 37, 13) quadratic residue (QR) code is proposed. According to the resulting I and J, one computes the unknown syndromes, and thus finds the corresponding error-locator polynomial by using an inverse-free BM algorithm. Based on the modified Chase-II algorithm, the performance of soft-decision decoding for the (73, 37, 13) QR code is given. This result is never seen in the literature, to our knowledge. Moreover, the error-rate performance of linear programming (LP) decoding for the (73, 37, 13) QR code is also investigated, and LP-based decoding is shown to be significantly superior in performance to the algebraic soft-decision decoding while requiring almost the same computational complexity.