Service re-routing for service network graph: efficiency, scalability and implementation

The key to success in Next Generation Network is service routing in which service requests may need to be redirected as in the case of the INVITE request in Session Initiation Protocol. Service Path (SPath) holds the authentication and server paths along side with service information. As the number of hops in a redirection increases, the length of SPath increases. The overhead for service routing protocols which uses SPath increases with the length of SPath. Hence it is desirable to optimize SPath to ensure efficiency and scalability of protocols involving service routing. In this paper, we propose a re-routing strategy to optimize service routing, and demonstrate how this strategy can be implemented using SPath to enhance the efficiency and scalability of Service Network Graph (SNG)

Improving the performance of SCTP Transport Protocol over wireless networks

[Abstract]: Stream Control Transmission Protocol(SCTP) is a reliable transport protocol combining the advantages of TCP and UDP. SCTP has many desirable features including multihoming, multistreaming, and partial data reliability. These features have made SCTP perform much more effectively in multimedia networking applications. They have also worked better in wireless environment which traditional transport protocols are ineffective and cumbersome. Before the transmission, an application using SCTP needs to establish an association between the client and the server. The establishment of association requires a number which will be used to create multiple streams. However, SCTP has not specified a method or suggested any ideas of determine the number. In our paper, we focus on the performance of SCTP protocol over the wireless networks. The ideas is to extend the SCTP with a process of determining an optimal number prior to the association establishing. We examine the modified SCTP on a simulated wireless networks, and the experiment results of simulation using NS2 have shown the modified SCTP is feasible and also demonstrated the modified SCTP’s superiority of performance over TCP and UDP over the wireless networks

REISCH: incorporating lightweight and reliable algorithms into healthcare applications of WSNs

Healthcare institutions require advanced technology to collect patients' data accurately and continuously. The tradition technologies still suffer from two problems: performance and security efficiency. The existing research has serious drawbacks when using public-key mechanisms such as digital signature algorithms. In this paper, we propose Reliable and Efficient Integrity Scheme for Data Collection in HWSN (REISCH) to alleviate these problems by using secure and lightweight signature algorithms. The results of the performance analysis indicate that our scheme provides high efficiency in data integration between sensors and server (saves more than 24% of alive sensors compared to traditional algorithms). Additionally, we use Automated Validation of Internet Security Protocols and Applications (AVISPA) to validate the security procedures in our scheme. Security analysis results confirm that REISCH is safe against some well-known attacks

An infrastructure for service authentication and authorization revocation in a dynamic aggregation of networks

[Abstract]: When a user requests a service from a server (SA), SA will authenticate the user based on some stored authentication information. If the information is stored on another server or network which is not accessible to SA or not in a compatible form of that required by SA, the identity of the user cannot be established. Without a global authentication service, authentication of users from another autonomous network is a major security issue in service sharing. In this paper, we extended Network Service Sharing Infrastructure (NSSI) by which many networks are linked together for service sharing. Within NSSI, individual networks authenticate and grant authorizations independent of each other by using their own authentication information repository (AIR). NSSI enables authentication and authorization results to be relayed to other linked networks to access a shared services while individual networks still maintain their own authentication scheme or authentication requirements. NSSI facilitates dynamic aggregation of networks for service sharing with minimum administrative overhead

The Effect of Self-repair on Judged Quality of Consecutive Interpreting: Attending to Content, Form and Delivery

This paper investigates the correlations between self-repair and subjective assessments of student interpreters’ performance in consecutive interpreting(CI). Twelve interpretations from an interpreting contest in China are transcribed, with the self-repairs identified and annotated based on Levelt’s classification (1983), including both overt and covert repairs. In addition to the final scores awarded at the contest, different methods and raters are used to assess the comprising aspects of an overall quality, namely content, form and delivery. Statistical analysis shows that: (1)overt repairs have a strong positive correlation with content, and moderate negative correlations with form and delivery; (2) form and delivery are negatively correlated with covert repairs, in terms of the frequencies of repetitions and pauses, and the mean length of pauses;(3) the judges’ overall assessments are more closely correlated with content than self-repairs. Finally, pedagogical implications for CI training are discussed, as are suggestions for future research