Low‐rate denial of service (LDoS) attack is a special DoS attack type of wireless sensor network (WSN). Routing protocol is the critical component of the WSN. Routing flood attack is a novel LDoS attack pattern in WSN. However, the attack is difficult to be detected by traditional intrusion detection algorithm. A novel LDoS attack detection method based on big data and signal analysis is proposed. Hilbert–Huang Transform (HHT) time–frequency signal analysis method is used to analyse the small non‐linear signal from LDoS attack traffic signal. Spark‐based Pearson and Spearman correlation coefficient calculation approaches are used to recognise the false intrinsic mode functions (IMFs) components decomposed by the HHT method. The effective threshold value of Pearson correlation coefficient is set to 0.2, the effective threshold value of Spearman correlation coefficient is set to 0.3, which are united to identify the false IMF components. SunSpot wireless nodes are used to build the wireless sensor nodes. If the difference between the IMF component and the normal IMF component is more than 40%, the LDoS attack will be detected. Experimental results show that this approach is effective to detect the LDoS attack in ZigBee WSN. This is a quantitative LDoS attack detection experimental research in WSN.

Due to widespread wireless broadband Internet, multimedia streaming using smart devices has become one urgent application. In this paper, we focus on how to improve the transmission performance when mobile users request multimedia streaming service on their smart devices. In this paper, smart devices are grouped to form one localized ad-hoc network using Bluetooth according to their social behavior and geographical locations. That is, if some users are willing to share the same multimedia objects and nearby within the Bluetooth coverage, they should cooperate to download the multimedia streams using the peer-to-peer (P2P) protocol through the Internet and the Bluetooth ad-hoc network simultaneously. Therefore, the proposed scheme based on the help of Bluetooth ad-hoc network not only offloads the inter-ISP traffic of P2P overlay network, but also saves the battery power of smart devices.

Content management systems (CMSs) are able to let people, who have no technical skill to manage websites, rapidly create, edit, organize and publish online contents. For example, CMSs are often used to establish e-commerce online shops, community portals, personal blogs, or organization websites. Thus, CMSs play the role of collecting data and then can be easily extended to become intelligent Internet systems. Most popular CMSs, e.g., Word Press and Joomla, rely on relational databases or SQL databases, e.g., MySQL, PostgreSQL, etc. However, due to the explosive growth of huge data, the well-structured characteristic of SQL databases may limit the scalability to handle horizontal scaling. Therefore, regarding the flexibility and the feasibility of parallel processing, cloud computing takes Not Only SQL (NoSQL) databases into consideration. How to migrate the original CMS software from SQL databases to NoSQL databases becomes one emerging and critical research issue. This paper is motivated to propose an autonomous SQL-to-NoSQL schema denormalization and migration. At the same time, this paper also evaluates the proposed mechanism on the realistic CMS software. Based on our experimental results, our mechanism not only helps the current CMS software migrate into the cloud platform without re-designing their database schemas, but also improves at least 45% access performance after schema migration.

When a number of persons, e.g., a family or a group of friends, drive their vehicles for a trip together, they can form a fleet of vehicles and share their network resources during their trip. Let one member want to watch a video from the Internet. He may not have high resolution or video quality due to his limited 3G/3.5G bandwidth to the Internet. The cooperative video streaming scenario allows the requested member to ask other members of the same fleet to download video cooperatively. In other words, other members can help to download parts of the video from the Internet and then forward video data to the requested member hop by hop through the ad-hoc network. This work proposes the k-hop cooperative video streaming protocol using H.264/SVC over the hybrid vehicular networks which consist of 3G/3.5G cellular network and Dedicated Short-Range Communications (DSRC) ad-hoc network. In order to smooth video playback over the DSRC-based ad-hoc network, this work proposes: (1) one streaming task assignment scheme that schedules the streaming task to each member over the dynamic vehicular networks, and (2) packet forwarding strategies that decide the forwarding sequence of the buffered video data to the requested member hop by hop. Finally, we utilize the network simulator version 2 (NS2) to simulate the proposed protocol. Based on the simulation results, the proposed scheme can estimate the assignment interval adaptively and the playback priority first (PPF) strategy has the best performance for the k-hop video forwarding over the hybrid vehicular networks.

ABSTRACT Network mobility (NEMO) enables a group of nodes to connect to the back‐end infrastructure during the movement. Because a vehicle must provide passengers good enough transmission quality, various access techniques, for example, 3 G/3.5 G, Wi‐Fi or dedicated short range communication, can be simultaneously equipped to aggregate bandwidth and tolerate link failure. This paper extends the Session Initiation Protocol (SIP)‐based NEMO framework to support multihoming. First, IEEE 802.21 Media Independent Handover (MIH) is integrated to manage multiple egress interfaces in an on‐board unit (OBU). Second, a dynamic synchronization mechanism using the SIP SUBSCRIBE and NOTIFY methods is proposed to manage multiple OBUs in a vehicle. Furthermore, the framework is applied to public transportation systems, for example, bus, train, or mass rapid transit. Passengers may need to transit several times during their journeys. The transit behavior must induce a flood of signaling messages for location update. In this paper, the SIP REFER method is exploited to reduce signaling messages while a group of passengers have scheduled their transit in advance. Copyright © 2011 John Wiley & Sons, Ltd.

Based on the clinic data, 69 % - 80 % stroke patients in Taiwan have the muscle weakness symptom of upper limb. Stroke patients are able to restore their independent living if they keep formal rehabilitation without interruption. However, due to the tedious and painful process, stroke patients may pause or suspend their rehabilitation therapy. Moreover, physiatrists in Taiwan hospitals must take care of more than one patient at the same time. This paper is motivated to propose a motor assessment system for stroke upper-limb rehabilitation. Our implementation is integrated with the Complete Minnesota Dexterity Test to quantify patients' recovery status automatically. Therefore, our implementation is able to reduce the workload of physiatrists effectively. In addition to assessment scale score, the proposed system is able to record more details, e.g., the tremor status and the grip strength, for doctors to evaluate the following rehabilitation therapy. Finally, a body-sensed game is provided to increase interest to the rehabilitation process.

When a passenger in a vehicle wants to watch video during movement, he may request video through cellular network, e.g., 3G or 3.5G network. However, due to the characteristics of vehicular networks, the limited bandwidth of 3G/3.5G network is not enough to support high resolution or high video quality. In order to improve the quality of video playback, this vehicle, which is defined as requester in this paper, may try to ask other members of the same fleet to download video cooperatively. In other words, other members would download parts of requested video through their 3G/3.5G network individually and then forward video data hop by hop to the requester using the DSRC ad-hoc network. In order to smooth the DSRC ad-hoc network, we propose and discuss two k-hop packet forwarding schemes for the aforementioned cooperative video streaming over vehicular networks in this paper. Each intermediary node of the forwarding route must decide how to deliver buffered video data through the limited DSRC network. Finally, the NS2 simulation tool is adopted to evaluate the proposed schemes. Based on the simulation results, the Playback Priority First (PPF) scheme is performed better than the First-In First-Out (FIFO) scheme.

When a vehicle requests a video streaming service from the Internet, it may not have enough bandwidth to receive good video quality. In order to resolve this problem, the vehicle is proposed to ask neighboring vehicles to help the video download process using a short-range wireless technique, i.e. Dedicated Short Range Communications (DSRCs). In this paper, this scenario is called cooperative streaming over vehicular networks. Since the topology of vehicular networks changes over time rapidly, three critical issues in the moving-vehicle-based cooperative streaming are: (i) how to form a cooperative group dynamically, (ii) how to schedule neighboring vehicles to help the video download process and (iii) how to estimate the possible change of network conditions. We propose corresponding control schemes to tackle the aforementioned issues in this paper. From the simulation results, we can find that different scheduling schemes are adaptive to different scenarios, and the proposed dynamic group formation scheme has better performance than that of periodic group formation scheme.

Due to the advance of wireless and mobile technologies, vehicular networks are widely discussed in recent years. When a vehicle requests a video stream from the Internet using the cellular network, i.e., 3G or 3.5G network, it may not have enough bandwidth to receive good quality of video. In order to resolve this problem, the vehicle can ask neighboring vehicles for the help of downloading the video stream. This scenario is called cooperative streaming in vehicular communications. The vehicle can communicate with neighboring vehicles using a short-range wireless technique, e.g., Dedicated Short Range Communications (DSRC). Since the topology of vehicle networks changes rapidly, two critical issues in the moving vehicle-based cooperative streaming are (1) how to form a cooperative group dynamically and (2) how to schedule neighboring vehicles to help the video downloading process. The simulation results reveal that the improvement of video quality is proportional to (1) high traffic flow, (2) high probability of willingness to share bandwidth and (3) low relative speed.

When a group of users or devices move together, network mobility resolves how to manage the location transition of the whole members. Two kinds of solutions have been proposed at different layers. Network mobility (NEMO) basic support protocol (BSP) is the extension of mobile IPv6 at the network layer. On the other hand, Session Initiation Protocol (SIP) based network mobility (SIP-NEMO) is defined at the application layer. However, on the perspective of ubiquitous network environment, a mobile router requires to possess several egress paths to the Internet for providing uninterrupted services and aggregating good enough bandwidth. Multihoming in network mobility support becomes one urgent and necessary issue. Since Mobile IPv6 based NEMO BSP, called MIPv6-NEMO hereafter for convenience, uses a bi-directional tunnel between home agent and mobile router, Multihomed MIPv6-NEMO would suffer and deepen header overhead and suboptimal routing. In the past, we have proposed SIP-NEMO to achieve route optimization. In this paper, we investigate and analyze how to extend the current SIP-NEMO to support multihoming further. The proposed multihomed SIP-NEMO is simulated in different cases and integrated with the IEEE 802.21 Media Independent Handover (MIH) standard. According to the simulation result, the SIP-NEMO can keep route optimization no matter which multihomed case is configured.

Network mobility is proposed to let a mobile network change its point of attachment and still keep all nodes attached to the mobile network globally reachable. However, due to finite bandwidth, limited signaling coverage and frequent link failure, a mobile network needs multihoming to access the Internet simultaneously on the perspective of performance and reliability. In this paper, we extends our previous work, i.e., SIP-based network mobility (SIP-NEMO), to support multihoming. A mobile network is considered to possess more than one egress gateway. The proposed multihomed SIP-NEMO provides dynamic synchronization among different egress gateways. Once an egress gateway joins or leaves the mobile network, the multihomed SIP-NEMO can establish or switch sessions on another alternative egress gateway. According to the simulation results, the proposed multihomed SIP-NEMO can achieve route optimization for data transmission.

Proxies can improve the quality of service (QoS) of clients in the three-tier networking architecture. However, it is more complicated to apply the server-proxy-client networking architecture to mobile networks for multimedia streaming because mobile clients possess the "keeping moving" characteristic. Therefore, the three-tier architecture in mobile networks must take user mobility into consideration, i.e., mobile clients should be able to switch to a proxy dynamically. In this paper, application-layer proxy handoff (APH) is defined to have applications be executed smoothly when mobile clients move in the server-proxy-client architecture. First, APH employs application-layer anycast to select one of the candidate proxies as the next proxy based on 1) the network condition between the mobile client and each candidate proxy and 2) the load balance among the candidate proxies. Second, APH utilizes IPv6 multicast to switch the session from the original proxy to the next proxy smoothly and to forward the available cache unsent in the original proxy to the next proxy for keeping the original session continuous

The movement of an entire mobile network is so-called "Network Mobility". Network mobility can widely apply to public transport, such as WLAN aboard. The IETF has proposed the NEMO basic support protocol to handle the network mobility problem. However, the NEMO basic support protocol results in sub-optimality that may not be tolerated by multimedia streaming services. In this paper, a framework, called SIP-NEMO, extends SIP to support network mobility. The proposed SIP-NEMO achieves route optimization not only when the caller and the callee are in different networks but also when the caller and callee are inside the same mobile network. Moreover, in order to save the bandwidth of wireless links, SIP-NEMO reduces the signaling messages using a URI-list service.

With the provision of various wireless services, e.g., third-generation (3G) and wireless local area network (WLAN), more and more people request to access the Internet anywhere at anytime. For example, people want to check their e-mails on the bus or watch online news while traveling in the train. For this purpose, the Internet Engineering Task Force (IETF) proposed the concept of network mobility, i.e., a set of users move as a unit. We motivate the network mobility problem by considering the state-of-the-art scenario of the network mobility (NEMO) basic support protocol that is extended from the Mobile IPv6 (MIPv6). In order to avoid the same problems suffered by MIPv6, a new session initiation protocol (SIP)-based network mobility management scheme called SIP-NEMO is designed and proposed in this paper. The proposed SIP-NEMO not only copes with the movement of a mobile network but also achieves the route optimization between two SIP clients without too many signaling messages over wireless links, even if the mobile network is nested. In this paper, we also analytically compute and simulate the performance of SIP-NEMO with the NEMO basic support protocol proposed by the IETF.

In a server-proxy-client 3-tier architecture of the wireless mobile network, proxies should be dynamically assigned to serve mobile hosts according to geographical dependency and the network situation. The goal of proxy handoff is to allow a mobile host still can receive packets from the corresponding server even though its served proxy is switched from the current one to the other one. A 3-tier multimedia mobile transmission platform, called MMTP, is proposed to solve the proxy handoff problem in the IPv6-based wireless mobile network. In MMTP, a proxy handoff scheme, which is based on the application layer anycast technique, is proposed to select from a number of candidate proxies according to the load balance concern and wireless network situation concern.