Network Tomography Application in Mobile Ad-hoc Network Using Stitching Algorithm

B. He, T. Tran, and B. Xie, “Authentication and identity management for secure cloud business and services,” Accepted for Book chapter in Cloud Computing, IGI Global, 2013.

M.S.S. Khana, Anup Kumar, Bin Xie, Prasanna K. Sahood

Abstract: In this paper, a network tomography (NT) approach is proposed to study network performance in ad-hoc networks. An analysis of network performance is presented in a dynamic MANET. An expectation–maximization (EM) algorithm is used in NT to estimate the network performance parameter in accordance with network performance observations. Over the dynamic network, a new algorithm has been proposed, called the stitching algorithm, to aggregate dynamic performance values for network links. Specifically, the stitching algorithm gives local and global performance parameters such as link delays over specified time periods. Therefore, the network behavior as well as the corresponding local network performance in a mobile network can be derived over a continuous period.

Keywords: Mobile network; Ad-hoc network; EM; MLE; Stitching algorithm

Secure Wireless Multicast for Delay-Sensitive Data via Network Coding (2013)

T. Tran, H. Li, W. Lin, L. Liu, and S. Khan “Secure Wireless Multicast for Delay-Sensitive Data via Network Coding,” IEEE Transactions on Wireless Communications, 2013.

Abstract:

Wireless multicast for delay-sensitive data is challenging because of the heterogeneity effect where each receiver may experience different packet losses. Fortunately, network coding, a new advanced routing protocol, offers significant advantages over the traditional Automatic Repeat reQuest (ARQ) protocols in that it mitigates the need for retransmission and has the potential to approach the min-cut capacity. Network-coded multicast would be, however, vulnerable to false packet injection attacks, in which the adversary injects bogus packets to prevent receivers from correctly decoding the original data. Without a right defense in place, even a single bogus packet can completely change the decoding outcome. Existing solutions either incur high computation cost or cannot withstand high packet loss. In this paper, we propose a novel scheme to defend against false packet injection attacks on network-coded multicast for delay-sensitive data. Specifically, we propose an efficient authentication mechanism based on null space properties of coded packets, aiming to enable receivers to detect any bogus packets with high probability. We further design an adaptive scheduling algorithm based on the Markov Decision Processes (MDP) to maximize the number of authenticated packets received within a given time constraint. Both analytical and simulation results have been provided to demonstrate the efficacy and efficiency of our proposed scheme.

On Achieving the Maximum Internet Capacity in Wireless Mesh Networks (2013)

Bin Xie, Haitang Wang, and Dharma P. Agrawal, "On Achieving the Maximum Internet Capacity in Wireless Mesh Networks," Submitted for Elsevier Journal of Ad Hoc Networks, 2013.

Abstract:

A Wireless Mesh Network (WMN) is connected by multiple wireless mesh routers that are able to operate multiple channels for increased network capacity. At the same time, the infrastructure such as Internet gateway provides the Internet connectivity and thus the mobile users in the network can access the Internet by multi-hop route of mesh routers. As other wireless networks, the network capacity is a fundamental issue in the WMN. The analytical results in this paper show that the upper bound of network capacity. Only when the number of Internet gateway nodes asymptotically grows with the number of mesh routers, the network capacity achieves significant capacity gain. We theoretically compute the WMN upper bounds of the infrastructure network capacity and its ad hoc capacity as well.

On Secure Communication in Integrated Heterogeneous Wireless Networks (2010)

Bin Xie, Anup Kumar, David Zhao, Ranga Reddy, "On Secure Communication in Integrated Heterogeneous Wireless Networks,” International Journal of Information Technology, Communications, and Convergence, to appear, 2010.

Abstract:

The next generation of mobile wireless systems targets to obtain ubiquitous connectivity services for mobile users through Heterogeneous Wireless Networks (HWNs), which integrate cellular network, WLAN, WiMAX, and MANET. It is essential to consider the security issue as one of the main objectives in developing HWNs. In this article, we discuss the security characteristics unique to HWNs and show how attacks against single or multi-hop wireless networks can be translated into powerful attacks against HWNs. We investigate various types of attacks against HWNs and provide an overview of existing solutions for security protection. We also identify underlying challenges in securing HWNs infrastructure and protecting the transmitted information.

Increasing Lifetime of Wireless Sensor Networks Using Controllable Mobile Cluster Heads (2009)

Torsha Banerjee, Bin Xie, Jung Hyan Jun, and Dharma P. Agrawal, “Increasing Lifetime of Wireless Sensor Networks Using Controllable Mobile Cluster Heads,” Accepted to appear in Wiely Wireless Communications and Mobile Computing (WCMC), 2009.

Abstract:

In a static wireless sensor network (WSN), sensors close to the base station (BS) run out of energy at a much faster rate than sensors in other parts of the network. This is because the sensor close to the BS always relays the data for other sensors, resulting in an unequal distribution of network residual energy. In this paper, we propose a scheme for enhancing the network lifetime using multiple mobile cluster heads (CHs) that can move in the WSN in a controllable manner. The CH controllably moves toward the energy-rich sensors or the event area, offering the benefits of maintaining the remaining energy more evenly, or eliminating multihop transmission. Therefore, the proposed scheme increases the network lifetime. We theoretically analyze the energy consumption in our scheme and propose three heuristical mobility strategies. We further study the collaboration among CHs in order to maintain their connectivity to the BS to ensure the delay requirement for real-time applications. Simulation shows that network lifetime is increased by upto 75% over existing approach by making CHs always move toward a stable equilibrium point. Our connectivity algorithm provides a best case improvement of 40% in transmission delays over existing schemes. Copyright © 2009 John Wiley & Sons, Ltd.

A Hybrid Network Coding Technique for Single-hop Wireless Networks (2009)

T. Tran, T. Nguyen, B. Bose, and V. Gopal, “A Hybrid Network Coding Technique for Single-hop Wireless Networks,” IEEE Journal on Selected Areas in Communications (JSAC)- Special Issue on Network Coding for Wireless Networks, June, 2009.

Abstract:

In this paper, we investigate a hybrid network coding technique to be used at a wireless base station (BS) or access point (AP) to increase the throughput efficiency of single-hop wireless networks. Traditionally, to provide reliability, lost packets from different flows (applications) are retransmitted separately, leading to inefficient use of wireless bandwidth. Using the proposed hybrid network coding approach, the BS encodes these lost packets, possibly from different flows together before broadcasting them to all wireless users. In this way, multiple wireless receivers can recover their lost packets simultaneously with a single transmission from the BS. Furthermore, simulations and theoretical analysis showed that when used in conjunction with an appropriate channel coding technique under typical channel conditions, this approach can increase the throughput efficiency up to 3.5 times over the automatic repeat request (ARQ), and up to 1.5 times over the HARQ techniques.

Wireless Broadcast Using Network Coding (2009)

D. Nguyen, T. Tran, T. Nguyen, and B. Bose, “Wireless Broadcast Using Network Coding,” IEEE Transactions on Vehicular Technology (TVT), Vol. 58, No. 2, February, 2009 (won Jack Neubauer Memorial award, 2012)

Abstract:

Traditional approaches to reliably transmit information over an error-prone network employ either forward error correction (FEC) or retransmission techniques. In this paper, we propose some network coding schemes to reduce the number of broadcast transmissions from one sender to multiple receivers. The main idea is to allow the sender to combine and retransmit the lost packets in a certain way so that with one transmission, multiple receivers are able to recover their own lost packets. For comparison, we derive a few theoretical results on the bandwidth efficiency of the proposed network coding and traditional automatic repeat-request (ARQ) schemes. Both simulations and theoretical analysis confirm the advantages of the proposed network coding schemes over the ARQ ones.

Coverage and Lifetime Optimization of Wireless Sensor Networks with Gaussian Distribution (2008)

Demin Wang, Bin Xie, and Dharma P. Agrawal, “Coverage and Lifetime Optimization of Wireless Sensor Networks with Gaussian Distribution,” IEEE Transaction on Mobile Computing (TMC), Volume 7, No.12, Pages 1444-1458, April 2008.

Abstract:

A wireless sensor network (WSN) has to maintain a desirable sensing coverage and periodically report sensed data to the administrative center (i.e., base station) and the reporting period may range from months to years. Coverage and lifetime are two paramount problems in a WSN due to constraint of associated battery power. All previous theoretical analysis on the coverage and lifetime is primarily focused on the random uniform distribution of sensors or some specific network scenarios (e.g., a controllable WSN). In this paper, we provide an analytical framework for the coverage and lifetime of a WSN that follows a two-dimensional Gaussian distribution. We also study the coverage and lifetime when the dimensions of Gaussian dispersion (i.e., x, y) admit different Gaussian parameters (i.e., standard deviation, sigmaxnesigmay). We identify intrinsic properties of coverage/lifetime in terms of Gaussian distribution parameters, which is a fundamental issue in designing a WSN. Following the results obtained, we further determine the sensor deployment strategies for a WSN that could satisfy a predefined coverage and lifetime. Two deployment algorithms are developed based on using our analytical models and are shown to effectively increase the WSN lifetime.

Intrusion Detection in Homogenous and Heterogenous Wireless Sensor Networks (2008)

Yun Wang, Xiaodong Wang, Bin Xie, Demin Wang and Dharma P. Agrawal, “Intrusion Detection in Homogenous and Heterogenous Wireless Sensor Networks,” IEEE Transaction on Mobile Computing (TMC), Volume 7, No. 6, Pages 698-711, 2008.

Abstract:

Intrusion detection in Wireless Sensor Network (WSN) is of practical interest in many applications such as detecting an intruder in a battlefield. The intrusion detection is defined as a mechanism for a WSN to detect the existence of inappropriate, incorrect, or anomalous moving attackers. For this purpose, it is a fundamental issue to characterize the WSN parameters such as node density and sensing range in terms of a desirable detection probability. In this paper, we consider this issue according to two WSN models: homogeneous and heterogeneous WSN. Furthermore, we derive the detection probability by considering two sensing models: single-singing detection and multiple-sensing detection. In addition, we discuss the network connectivity and broadcast reachability, which are necessary conditions to ensure the corresponding detection probability in a WSN. Our simulation results validate the analytical values for both homogeneous and heterogeneous WSNs.

Enabling Multi-Service on 3G and Beyond: Challenges and Future Directions (2008)

Bin Xie, Anup Kumar, and Dharma P. Agrawal, “Enabling Multi-Service on 3G and Beyond: Challenges and Future Directions,” IEEE Wireless Communication Magazine , Volume 15, Issue 3, Pages 66-72, June 2008.

Abstract:

The next generation of mobile wireless system is expected to allow a multimode terminal to simultaneously access multiple networks for a variety of services with an appropriate quality of service. To achieve such a goal, many technologies such as multimode terminals, QoS-based network selection, and mobility management should be effectively incorporated into wireless network systems. This article discusses the current progress in network architecture as well as the functionalities of a multimode terminal, and identifies the fundamental research issues for future work in such a heterogeneous wireless environment.

Selfishness in Mesh Networks: Wired Multihop MANETs (2008)

Lakshmi Santhanam, Bin Xie, and Dharma P. Agrawal, “Selfishness in Mesh Networks: Wired Multihop MANETs,” IEEE Wireless Communication Magazine , Volume 15, Issue 4, Pages 16-23, August, 2008.

Abstract:

A wireless mesh network is a wired extension of a multihop ad hoc network that defines a new paradigm for broadband wireless Internet access. A packet originating from a mesh client is relayed collaboratively in a multihop fashion by the intermediate mesh routers toward an Internet gateway. All existing mesh routing protocols assume that each MR honestly participates in packet forwarding. This is valid only in a network managed by a single trusted authority. However, a community-based WMN can be formed by a group of independent MRs operated by different service providers. It is a real challenge to establish a priori trust in a multi-operator WMN. In such a situation, a selfish MR might be motivated to monopolize the wireless channel for itself by intentionally dropping others' packets. This results in severe performance degradation. Thus, enforcing collaboration is a determinant aspect in designing a secure and reliable WMN. In this article we analyze selfishness of MRs in a multi-operator WMN and explore its overall negative impact on network performance. We finally present a summary of various existing schemes with respect to detecting selfishness, analyze their usefulness in WMNs, and highlight their relative advantages and deficiencies.

Issues in Integrating Cellular Networks, WLANs, and MANETs: A Futuristic Hetero-geneous Wireless Network (2005)

D. Cavalcanti, C. M. Cordeiro, D. P. Agrawal, Bin Xie, and A. Kumar, "Issues in Integrating Cellular Networks, WLANs, and MANETs: A Futuristic Hetero- geneous Wireless Network," IEEE Wireless Communications Magazine, Special Issue on Toward Seamless Internetworking of Wireless LAN and Cellular Net- works, Volume 12, Issue 3, Pages 30-41, 2005.

Abstract:

The popularity of wireless communication systems can be seen almost everywhere in the form of cellular networks, WLANs, and WPANs. In addition, small portable devices have been increasingly equipped with multiple communication interfaces building a heterogeneous environment in terms of access technologies. The desired ubiquitous computing environment of the future has to exploit this multitude of connectivity alternatives resulting from diverse wireless communication systems and different access technologies to provide useful services with guaranteed quality to users. Many new applications require a ubiquitous computing environment capable of accessing information from different portable devices at any time and everywhere. This has motivated researchers to integrate various wireless platforms such as cellular networks, WLANs, and MANETs. Integration of different technologies with different capabilities and functionalities is an extremely complex task and involves issues at all layers of the protocol stack. This article envisions an architecture for state-of-the-art heterogeneous multihop networks, and identifies research issues that need to be addressed for successful integration of heterogeneous technologies for the next generation of wireless and mobile networks.

Load-balancing and Inter-domain Mobility for Wireless Mesh Networks (2008)

Bin Xie, Yingbing Yu, Anup Kumar, and Dharma P. Agrawal, “Load-balancing and Inter-domain Mobility for Wireless Mesh Networks,” Elsevier Journal of Parallel and Distributed Computing (JPDC), Volume 68, Issue 6, Pages 825-839 June 2008.

Abstract:

This paper proposes a scheme for domain partition to achieve the tradeoff between load-balancing and inter-domain mobility to reduce the negative impact of the host mobility. The load-balancing scheme for domains includes: an initialization procedure to divide a mesh network into domains, and a load adjustment procedure to rebalance the traffic load of neighboring domains when required. Moreover, the proposed scheme provides inter-domain mobility in support of multi-hop communication with the multi-hop cellular IP (MCIP) mobility protocol. Our experimental results show that the proposed protocol effectively controls the migration of mesh routers as well as mobile stations.

ROPAS: Cross-layer Cognitive Architecture for Mobile UWB Networks (2008)

Chittabrata Goash, Bin Xie, and Dharma P. Agrawal, “ROPAS: Cross-layer Cognitive Architecture for Mobile UWB Networks,” Springer Journal of Computer Science and Technology (JCST), Invited submission as best paper form 4th IEEE International Conference on Mobile Ad hoc and Sensor Systems (MASS), Volume 23, Issue 3, Pages 413-425, May 2008.

Abstract:

The allocation of bandwidth to unlicensed users, without significantly increasing the interference on the existing licensed users, is a challenge for Ultra Wideband (UWB) networks. Our research work presents a novel Rake Optimization and Power Aware Scheduling (ROPAS) architecture for UWB networks. Since UWB communication is rich in multipath effects, a Rake receiver is used for path diversity. Our idea of developing an optimized Rake receiver in our ROPAS architecture stems from the intention of reducing the computation complexity in terms of the number of multiplications and additions needed for the weight derivation attached to each finger of the Rake receiver. Our proposed work uses the Cognitive Radio (CR) for dynamic channel allocation among the requesting users while limiting the average power transmitted in each sub-band. In our proposed novel ROPAS architecture, dynamic channel allocation is achieved by a CR-based cross-layer design between the PHY and Medium Access Control (MAC) layers. Additionally, the maximum number of parallel transmissions within a frame interval is formulated as an optimization problem. This optimal decision is based on the distance parameter between a transmitter-receiver pair, bit error rate and frequency of request by a particular application. Moreover, the optimization problem improvises a differentiation technique among the requesting applications by incorporating priority levels among user applications. This provides fairness and higher throughput among services with varying power constraint and data rates required for a UWB network.

Fault Tolerant Multiple Event Detection in a Wireless Sensor Network (2008)

Torsha Banerjee, Bin Xie, and Dharma P. Agrawal, “Fault Tolerant Multiple Event Detection in a Wireless Sensor Network,” Elsevier Journal of Parallel and Distributed Computing (JPDC), Volume 68, Issue 9, Pages 1222-1234, September, 2008.

Abstract:

With an increasing acceptance of Wireless Sensor Networks (WSNs), the health of individual sensor is becoming critical in identifying important events in the region of interest. One of the key challenges in detecting event in a WSN is how to detect it accurately transmitting minimum information providing sufficient details about the event. At the same time, it is also important to devise a strategy to handle multiple events occurring simultaneously. In this paper, we propose a Polynomial-based scheme that addresses these problems of Event Region Detection (PERD) by having a aggregation tree of sensor nodes. We employ a data aggregation scheme, TREG (proposed in our earlier work) to perform function approximation of the event using a multivariate polynomial regression. Only coefficients of the polynomial (P) are passed instead of aggregated data. PERD includes two components: event recognition and event report with boundary detection. This can be performed for multiple simultaneously occurring events. We also identify faulty sensor(s) using the aggregation tree. Performing further mathematical operations on the calculated P can identify the maximum (max) and minimum (min) values of the sensed attribute and their locations. Therefore, if any sensor reports a data value outside the [min, max] range, it can be identified as a faulty sensor. Since PERD is implemented over a polynomial tree on a WSN in a distributed manner, it is easily scalable and computation overhead is marginal. Results reveal that event(s) can be detected by PERD with error in detection remaining almost constant achieving a percentage error within a threshold of 10% with increase in communication range. Results also show that a faulty sensor can be detected with an average accuracy of 94% and it increases with increase in node density.

Optimizing Deployment of Internet Gateway in Wireless Mesh Networks (2008)

Bing He, Bin Xie, and Dharma P. Agrawal, “Optimizing Deployment of Internet Gateway in Wireless Mesh Networks, ” Elsevier Computer Communications Special Issue on Wireless Mesh Networks, Volume 31, Issue 7, Pages 1259-1275, May 2008.

Abstract:

In a wireless mesh network (WMN), mesh routers (MRs) are interconnected by wireless links and form a wireless backbone to provide ubiquitous high-speed Internet connectivity for mobile clients. The wireless backbone is tightly integrated with the Internet by nodes called as Internet gateways (IGWs). In this paper, we address the IGW deployment problem which is shown to be NP-hard. We first formulate it as a linear program (LP) issue, then develop two heuristic algorithms for the purpose of cost-efficient IGW deployment. We further compare our algorithms with a leading approach by extensive simulations. Our analysis shows the effectiveness of the proposed algorithms.

Combating the Bloated State Problem in Mobile Agents based Network Monitoring Applications (2008)

Vijay. K Verma, Ramesh. C. Joshi, Bin Xie, Dharma P. Agrawal, “Combating the Bloated State Problem in Mobile Agents based Network Monitoring Applications,” Elsevier Computer Networks Journal (COMNET), Volume 52, Issue 17, Pages 3218-3228, 2008.

Abstract:

As computer networks increase in size, it is critical to provide efficient and scalable network management. Integration of mobile agents (MAs) with simple network management protocol (SNMP) provides a decentralized network management architecture that overcomes the limitations of the legacy SNMP client/server structure. However, as an MA travels through its itinerary, acquiring the network state at each managed node, its size linearly increases node-by-node and it may be unexpectedly bloated. As a result, a bloated MA will have difficulty in migrating from one node to another. We show that the network response time grows exponentially as the MA size increases linearly. In this paper, we propose a new strategy called itinerary partitioning approach (IPA) that exploits cloning capability of MAs to effectively address this bloated state phenomenon. The analytical model shows the effectiveness of our proposed IPA in terms of network response time. We have implemented the IPA in a practical test-bed network and the results seem to be very encouraging.

Decentralized Key Generation Scheme for Cellular-Based Heterogeneous Wireless Ad hoc Networks (2007)

Ananya Gupta, Anindo Mukherjee, Bin Xie, and Dharma P. Agrawal, “Decentralized Key Generation Scheme for Cellular-Based Heterogeneous Wireless Ad hoc Networks,” Elsevier Journal of Parallel and Distributed Computing (JPDC), Volume 67, Issue 9, Pages 981-991, September 2007.

Abstract:

With the support of cellular system a cellular-based mobile ad hoc network (MANET) offers promising communication scenarios while entails secure data exchange as other wireless systems. In this paper, we propose a novel decentralized key generation mechanism using shared symmetric polynomials in which the base stations (BSs) carry out an initial key generation by a symmetric polynomial in a distributed manner and then pass on the key material to mobile stations (MSs). Thereafter, our proposed key generation scheme enables each pair of MSs to establish a pairwise key without any intervention from the BS, thus reducing the management cost for the BS. The shared key between two MSs is computed without any interaction between them. In addition, the trust among MSs is derived from the cellular infrastructure, thus enjoying an equal security level as provided in the underlying cellular network. Simulations are done to observe the system performance and the results are very encouraging.

Secure Interconnection Protocol for Integrated Internet and Ad Hoc Networks (2007)

Bin Xie, Anup Kumar, and Dharma P. Agrawal, “Secure Interconnection Protocol for Integrated Internet and Ad Hoc Networks,” Wiley Wireless Communications and Mobile Computing (WCMC), Volume 7, Pages 1-20, September 2007.

Abstract:

Integration of ad hoc networks with the Internet provides global Internet connectivity for ad hoc hosts through the coordination of mobile IP and ad hoc protocols. In a pure ad hoc network, it is difficult to establish trust relationship between two ad hoc hosts due to lack of infrastructure or centralized administration. In this paper, an infrastructure-supported and distributed authentication protocol is proposed to enhance trust relationships amongst ad hoc hosts. In addition, an effective secure routing protocol (SRP) is discussed to protect the multi-hop route for Internet and ad hoc communication. In the integrated ad hoc networks with Internet accessibility, the ad hoc routing security deployed with the help of infrastructure has a fundamental impact on ad hoc hosts in term of Internet access, integrity, and authentication. Both analysis and simulation results demonstrate the effectiveness of the proposed security protocol.

Securing Macro/micro mobility for Multi-hop Cellular IP (2006)

Bin Xie, and Anup Kumar, Dharma P. Agrawal, and S. Srinivasan “Securing Macro/micro mobility for Multi-hop Cellular IP,” Elsevier Special Issue of Pervasive and Mobile Computing (PMC) Journal on Security in Wireless Mobile Computing, Volume 2, Issue 2, Pages 111-136, 2006.

Abstract:

A Multi-hop Cellular IP (MCIP) network differentiates global and local domains in terms of macro/micro-mobility in heterogeneous multi-hop communication. However, a MCIP network is vulnerable to various attacks and compromises during macro/micro-mobility processes in an adversarial environment. Existing MCIP protocol does not provide macro/micro-mobility security protection for mobile stations. In this paper, we introduce and evaluate a secure macro/micro-mobility protocol (SM3P). In the proposed SM3P, mobile IP security has been extended for supporting macro-mobility across local domains through the process of multi-hop registration and authentication. In a MCIP local domain, a certificate-based authentication achieves the effective routing and micro-mobility protection from a range of potential security threats. Our evaluation and simulation demonstrates the effectiveness of the SM3P.

Multi-hop Cellular IP: A New Approach to Heterogeneous Wireless Networks (2006)

Bin Xie, Anup Kumar, D. Cavalcanti, and Dharma P. Agrawal “Multi-hop Cellular IP: A New Approach to Heterogeneous Wireless Networks,” International Journal of Pervasive Computing and Communications (IJPCC), Volume 2, Issue 4, Pages 370 - 383 March, 2006.

Abstract:

This paper proposes a new Heterogeneous Multi-hop Cellular IP (MCIP) network that integrates multi-hop communication with Cellular IP. MCIP increases the coverage of the wireless network and improves the network robustness against adverse propagation phenomena by supporting communication in dead zones and areas with poor radio coverage. MCIP includes three components: location management, connection management and route reconfiguration. Location management is responsible for maintaining the location information for Mobile Stations (MSs) in a local domain. Connection management establishes an initial path for data transmission and a route reconfiguration mechanism is proposed to take advantage of various multi-hop connection alternatives available based on terminal interfaces, network accessibility and topology. Our simulation results show that MCIP performs well in networks of various sizes including scalability, throughput, and packet delay.

Issues in Integrating Cellular Networks, WLANs, and MANETs: A Futuristic Heterogeneous Wireless Network (2005)

D. Cavalcanti, C. M. Cordeiro, D. P. Agrawal, Bin Xie, and A. Kumar, “Issues in Integrating Cellular Networks, WLANs, and MANETs: A Futuristic Heterogeneous Wireless Network,” IEEE Wireless Communications Magazine, Special Issue on Toward Seamless Internetworking of Wireless LAN and Cellular Networks, Volume 12, Issue 3, Pages 30-41, 2005.

Abstract:

The popularity of wireless communication systems can be seen almost everywhere in the form of cellular networks, WLANs, and WPANs. In addition, small portable devices have been increasingly equipped with multiple communication interfaces building a heterogeneous environment in terms of access technologies. The desired ubiquitous computing environment of the future has to exploit this multitude of connectivity alternatives resulting from diverse wireless communication systems and different access technologies to provide useful services with guaranteed quality to users. Many new applications require a ubiquitous computing environment capable of accessing information from different portable devices at any time and everywhere. This has motivated researchers to integrate various wireless platforms such as cellular networks, WLANs, and MANETs. Integration of different technologies with different capabilities and functionalities is an extremely complex task and involves issues at all layers of the protocol stack. This article envisions an architecture for state-of-the-art heterogeneous multihop networks, and identifies research issues that need to be addressed for successful integration of heterogeneous technologies for the next generation of wireless and mobile networks.

A Protocol for Efficient Bi-directional Connectivity between Ad hoc networks and Internet (2005)

Bin Xie, and Anup Kumar, “A Protocol for Efficient Bi-directional Connectivity between Ad hoc networks and Internet,” Journal of Internet Technology (JIT), Special Issue on Wireless Ad hoc and Sensor Networks, Volume 6, No. 1, Pages 101-109, 2005.

Abstract:

The integration of infrastructure networks and ad hoc mobile networks can be used to eliminate dead zones in wireless LANs and cellular networks, and can also be used to extend the coverage of wireless networks. Earlier approaches for the integrated networks either provided only unidirectional global connectivity for ad hoc hosts or caused high overhead and packet delay for bi-directional connections. In this paper, a protocol for integrating mobile IP and enhanced DSDV (EDSDV) is proposed to provide bi-directional Internet connectivity for ad hoc hosts. A detailed performance comparison is conducted between the proposed approach with a leading integration approach based on different network sizes, mobility of ad hoc hosts and other network parameters. The experimental results show that the proposed approach has smaller overhead for bi-directional connectivity and shorter average packet delay compared to the leading integration approach.