An evolvable, scalable, and resilient control channel for software defined wireless access networks

AbstractThis paper presents a novel multipath communication-based OpenFlow channel for Software Defined Wireless Access Networks (SDWANs), namely mOpenFlow. The advantageous features of mOpenFlow include the following: (i) resilience and scalability in wireless environments, (ii) evolvability of the existing access networks and the OpenFlow standard, (iii) a novel network calculus-based model for performance analysis of mOpenFlow. By leveraging the multipath communication for conveying OpenFlow traffic, mOpenFlow enhances both robustness (i.e., resilience) and throughput (i.e., scalability) of the control channel. To achieve the evolvability, mOpenFlow adopts the multipath transport control protocol, which conforms to SDWANs and the OpenFlow standard. We evaluate mOpenFlow in an emulated SDWAN in relation to the standard channel. The results show that mOpenFlow outperforms the standard channel, both in terms of robustness and scalability. Additionally, the numerical results indicate that the model provides a fast and reliable way for analyzing the end-to-end delay on mOpenFlow

The world-first deployment of narrowband IoT for rural hydrological monitoring in UNESCO biosphere environment

The success of a rural wireless monitoring system depends on establishing a reliable wireless link over the TCP/IP communication protocol in a challenging terrain and elevation profile. Several studies have shown that link reliability in a rural area can neither be predicted with high accuracy nor precisely modeled using existing mathematical channel modeling tools. Hence, the use of the empirical approach to infer wireless link reliability. This work focuses on the revival of a rural hydrological/water monitoring system with emphasis on the wireless link located in Tasik Chini, a lake with UNESCO biosphere status. The contributions of this study include: understudy the link reliability of a centralized wireless sensor network infrastructure system using the 2G and Long Range (LoRa) wireless network, the performance limitation of the low data wireless sensor network in a rural environment, approaches to revive rural water station monitoring center and finally highlight potential opportunities in rural wireless communications. View les

Autoantibodies against matrix metalloproteinase-1 in patients with localized scleroderma

Background: Localized scleroderma (LSc) is characterized by cutaneous fibrosis and various autoantibodies. Objective: To determine the presence or levels of antibodies (Abs) against matrix metalloproteinase (MMP)-1 and their clinical relevance in LSc. Methods: Anti-MMP-1 Ab was examined by ELISA (Enzyme-Linked ImmunoSorbent Assay) and immunoblotting using human recombinant MMP-1. MMP-1 collagenase activity was determined using biotinylated collagen as substrate and the amount of cleaved biotinylated fragments of collagen by MMP-1 was measured by ELISA. Results: LSc patients exhibited significantly elevated IgG anti-MMP-1 Ab levels relative to normal controls at similar level of patients with systemic sclerosis (SSc). However, IgG anti-MMP-1 Ab levels were comparable among the 3 LSc subgroups: morphea, linear scleroderma, and generalized morphea. When absorbance values higher than the mean + 2S.D. of normal controls were considered positive, IgG or IgM anti-MMP-1 Ab was found in 46% and 49% of total LSc patients and SSc patients, respectively. Anti-MMP-1 Ab was detected most frequently in morphea patients (60%), followed by linear scleroderma patients (47%) and then generalized morphea patients (25%). LSc patients positive for IgG anti-MMP-1 Ab had elevated levels of IgG anti-single-stranded DNA Ab, IgG anti-nucleosome Ab, and shorter disease duration relative to those negative. The presence of anti-MMP-1 Ab in LSc patients was confirmed by immunoblotting. IgG isolated from LSc patients\u27 sera positive for IgG anti-MMP-1 Ab by ELISA inhibited MMP-1 collagenase activity. Conclusion: These results suggest that anti-MMP-1 autoantibody is a novel autoantibody in LSc. c 2008 Japanese Society for Investigative Dermatology