Detection and isolation of wormhole nodes in wireless ad hoc networks based on post-wormhole actions.

The wormhole attack is one of the most treacherous attacks projected at the routing layer that can bypass cryptographic measures and derail the entire communication network. It is too difficult to prevent a priori; all the possible countermeasures are either too expensive or ineffective. Indeed, literature solutions either require expensive hardware (typically UWB or secure GPS transceivers) or pose specific constraints to the adversarial behavior (doing or not doing a suspicious action). The proposed solution belongs to the second category because the adversary is assumed to have done one or more known suspicious actions. In this solution, we adopt a heuristic approach to detect wormholes in ad hoc networks based on the detection of their illicit behaviors. Wormhole and post wormhole attacks are often confused in literature; that's why we clearly state that our methodology does not provide a defence against wormholes, but rather against the actions that an adversary does after the wormhole, such as packet dropping, tampering with TTL, replaying and looping, etc. In terms of contributions, the proposed solution addresses the knock-out capability of attackers that is less targeted by the researcher's community. In addition, it neither requires any additional hardware nor a change in it; instead, it is compatible with the existing network stack. The idea is simulated in ns2.30, and the average detection rate of the proposed solution is found to be 98-99%. The theoretical time to detect a wormhole node lies between 0.07-0.71 seconds. But, from the simulation, the average detection and isolation time is 0.67 seconds. In term of packet loss, the proposed solution has a relatively overhead of [Formula: see text] 22%. It works well in static and mobile scenarios, but the frame losses are higher in mobile scenarios as compared to static ones. The computational complexity of the solution is O(n). Simulation results advocate that the solution is effective in terms of memory, processing, bandwidth, and energy cost. The solution is validated using statistical parameters such as Accuracy, Precision, F1-Score and Matthews correlation coefficient ([Formula: see text]).

Performance analysis: Securing SIP on multi-threaded/multi-core proxy server using public keys on Diffie-Hellman (DH) in single and multi-server queuing scenarios.

The rapid replacement of PSTN with VOIP networks indicates the definitive phase-out of the PBX/PABX with smartphone-based VOIP technology that uses WLAN connectivity for local communication; however, security remains a key issue, regardless of the communication coverage area. Session initiation protocol (SIP) is one of the most widely adopted VOIP connection establishment protocols but requires added security. On the Internet, different security protocols, such as HTTPS (SSL/TLS), IPSec, and S/MIME, are used to protect SIP communication. These protocols require sophisticated infrastructure and some pose a significant overhead that may deteriorate SIP performance. In this article, we propose the following: i) avoid using Internet bandwidth and complex Internet protocols for local communication within an organization, but harness WLAN connectivity, ii) use multi-threaded or multicore computer systems to handle concurrent calls instead of installing hardware-based SIP servers, and iii) run each thread in a separate core. Cryptography is a key tool for securely transmitting confidential data for long- and short-range communication, and the Diffie-Hellman (DH) protocol has consistently been a popular choice for secret key exchanges. Primarily, used for symmetric key sharing, it has been proven effective in generating public/private key pairs, sharing public keys securely over public channels, and subsequently deriving shared secret keys from private/public keys. This key exchange scheme was proposed to safeguard VOIP communication within WLANs, which rely on the SIP for messaging and multimedia communication. For ensuring an efficient implementation of SIP, the system was rigorously analyzed using the M/M/1 and M/M/c queuing models. We analyze the behavior of SIP servers with queuing models with and without end-to-end security and increase users' trust in SIP security by providing a transparent sense of end-to-end security as they create and manage their private and public keys instead of relying on the underlying SIP technology. This research implements instant messaging, voice conversation, and secret key generation over DH while implementing and observing the role of multi-threading in multiqueue systems that serve incoming calls. By increasing the number of threads from one to two, the SIP response time improved from 20.23809 to 0.08070 min at an arrival rate of 4250 calls/day and a service rate of three calls/min. Similarly, by adding one to seven threads, the queue length was reduced by four calls/min. Implementing secure media streaming and reliable AES-based signaling for session confidentiality and integrity introduces a minor 8-ms tradeoff in SIP service performance. However, the advantages of implementing added security outweigh this limitation.

An Energy-Efficient Routing Protocol with Reinforcement Learning in Software-Defined Wireless Sensor Networks.

The enormous increase in heterogeneous wireless devices operating in real-time applications for Internet of Things (IoT) applications presents new challenges, including heterogeneity, reliability, and scalability. To address these issues effectively, a novel architecture has been introduced, combining Software-Defined Wireless Sensor Networks (SDWSN) with the IoT, known as the SDWSN-IoT. However, wireless IoT devices deployed in such systems face limitations in the energy supply, unpredicted network changes, and the quality of service requirements. Such challenges necessitate the careful design of the underlying routing protocol, as failure to address them often results in constantly disconnected networks with poor network performance. In this paper, we present an intelligent, energy-efficient multi-objective routing protocol based on the Reinforcement Learning (RL) algorithm with Dynamic Objective Selection (DOS-RL). The primary goal of applying the proposed DOS-RL routing scheme is to optimize energy consumption in IoT networks, a paramount concern given the limited energy reserves of wireless IoT devices and the adaptability to network changes to facilitate a seamless adaption to sudden network changes, mitigating disruptions and optimizing the overall network performance. The algorithm considers correlated objectives with informative-shaped rewards to accelerate the learning process. Through the diverse simulations, we demonstrated improved energy efficiency and fast adaptation to unexpected network changes by enhancing the packet delivery ratio and reducing data delivery latency when compared to traditional routing protocols such as the Open Shortest Path First (OSPF) and the multi-objective Q-routing for Software-Defined Networks (SDN-Q).

ISO/IEEE 11073 PHD message generation toolkit to standardize healthcare device.

As senior population increases, various healthcare devices and services are developed such as fall detection device, home hypertension management service, and etc. However, to vitalize healthcare devices and services market, standardization for interoperability between device and service must precede. To achieve the standardization goal, the IEEE 11073 Personal Health Device (PHD) group has been standardized many healthcare devices, but until now there are few devices compatible with the PHD standard. One of main reasons is that it isn't easy for device manufactures to implement standard communication module by analyzing standard documents of over 600 pages. In this paper, we propose a standard message generation toolkit to easily standardize existing non-standard healthcare devices. The proposed toolkit generates standard PHD messages using inputted device information, and the generated messages are adapted to the device with the standard state machine file. For the experiments, we develop a reference H/W, and test the proposed toolkit with three healthcare devices: blood pressure, weighting scale, and glucose meter. The proposed toolkit has an advantage that even if the user doesn't know the standard in detail, the user can easily standardize the non-standard healthcare devices.

Ladder-type SAW filters using thinned density of randomly distributed "hot" electrodes.

A new method for the design of relatively narrowband ladder-type SAW filters is proposed. It consists of the thinning procedure and consecutive randomization of positions of the remaining transductive periods inside the IDT to suppress undesirable additional passbands. A 0.9% fractional bandwidth filter on LiTaO(3) 42°-cut was designed and manufactured using the proposed approach.

Finding the evidence for protein-protein interactions from PubMed abstracts.

MOTIVATION: Protein-protein interactions play critical roles in biological processes, and many biologists try to find or to predict crucial information concerning these interactions. Before verifying interactions in biological laboratory work, validating them from previous research is necessary. Although many efforts have been made to create databases that store verified information in a structured form, much interaction information still remains as unstructured text. As the amount of new publications has increased rapidly, a large amount of research has sought to extract interactions from the text automatically. However, there remain various difficulties associated with the process of applying automatically generated results into manually annotated databases. For interactions that are not found in manually stored databases, researchers attempt to search for abstracts or full papers. RESULTS: As a result of a search for two proteins, PubMed frequently returns hundreds of abstracts. In this paper, a method is introduced that validates protein-protein interactions from PubMed abstracts. A query is generated from two given proteins automatically and abstracts are then collected from PubMed. Following this, target proteins and their synonyms are recognized and their interaction information is extracted from the collection. It was found that 67.37% of the interactions from DIP-PPI corpus were found from the PubMed abstracts and 87.37% of interactions were found from the given full texts. AVAILABILITY: Contact authors.

BioProber: software system for biomedical relation discovery from PubMed.

The numbers of articles and journals that are published are increasing at a considerable rate, and the published information is growing continuously and fast. Because of this, researches to acquire knowledge automatically have been carried out in the areas of information retrieval, information extraction and text mining. Information retrieval approaches are good for specific topics that the number of related articles is small. But, if the number is bigger, searching skill and knowledge acquisition ability are useless. Though many efforts have been made to extract information from literature, many approaches have concentrated on specific entities, such as proteins, genes and their interactions, and much information is still remained in unstructured text. So, we have developed a system that discovers relations between various categories of biomedical entities. Our system collects abstracts from PubMed by queries representing a topic and visualizes relationship from the collection by automatic information extraction.

Effects of purified persimmon tannin and tannic acid on survival and reproduction of bean bug, Riptortus clavatus.

We evaluated the effects of tannic acid and purified perrsimmon tannin on survival and reproduction of bean bugs, Riptortus clavatus.Feeding behavior of R. clavatus was also examined on sweet (cv. Fuyu) and astringent (cv. Chongdosi) persimmon fruits. Soluble tannin in sweet persimmon fruits decreased from 3% in early June to 0.5% in late September, but it increased from 2 to 8% during the same period in astringent persimmon fruits. More bugs visited sweet than astringent persimmon. Numbers of piercing/sucking spots were higher on sweet than on astringent persimmon. When fed 1 and 3% solutions of persimmon tannin, adult bugs ingested only 64.1 and 9.5% of the amount of water ingested by those offered the control (distilled water). Amounts of persimmon tannin ingested by the adult bugs were 6.5 and 2.8 times higher at 1 and 3% tannin solutions compared to a 0.1% solution. Persimmon tannin exerted negative effects on survival and reproduction of R. clavatus at higher concentrations (1 and 3% solutions). Feeding of R. clavatus adults decreased with increasing tannin concentrations. When results from both sexes were pooled, 50% mortality was achieved at 11 and 4 days after treatment with the 1 and 3% tannin solutions, respectively. Reproduction decreased with 1% tannin, and no eggs were produced with 3% tannin solution. Tannic acid was similar in its effects on R. clavatus. All nymphs died 14, 12, and 7 days after feeding on 0.1, 1, and 3% tannic acid, respectively. Adults were less sensitive than nymphs, and their survival was not affected by 0.1% tannic acid. However. 1 and 3% tannic acid solutions were fatal. Survivorship decreased to 50% at 11 and 6 days after supplying tannin solutions of 1 and 3% concentrations. Higher concentrations (1 and 3%) resulted in reduced reproduction, as was seen with persimmon tannin. Our data may explain why R. clavatus does not invade sweet persimmon orchards until late July, when concentrations of soluble tannin are low enough to allow them to feed.

Biomonitoring of coastal pollution status using protozoan communities with a modified PFU method.

Structural and functional parameters of protozoan communities were assessed as indicators of water quality in Korean coastal waters in the summer of 2000. A modified polyurethane foam unit (PFU) method, named the bottled PFU (BPFU) system, was used in order to carry out the bioassessment. Both parameters suggested that biomonitoring using the BPFU system was more effective than the conventional PFU method in offshore areas. The species number collected by the BPFU system generally decreased as pollution intensity increased at three main stations and was greater than that collected using the PFU method (paired t-test, t = 4.83, p < 0.0001). The Margalef diversity index coincided well with the water conditions. The diversity index values calculated from the BPFU system were also significantly higher than those from the PFU method (paired t-test, t = 5.37, p < 0.0001). Furthermore, the functional parameters, i.e. S(eq),G and T90%, correlated with the pollution status and could thus clearly discriminate the different classes of water quality.