Detecting unauthorized and compromised nodes in mobile ad hoc networks

Security of mobile ad-hoc networks (MANET) has become a more sophisticated problem than security in other networks, due to the open nature and the lack of infrastructure of such networks. In this paper, the security challenges in intrusion detection and authentication are identified and the different types of attacks are discussed. We propose a two-phase detection procedure of nodes that are not authorized for specific services and nodes that have been compromised during their operation in MANET. The detection framework is enabled with the main operations of ad-hoc networking, which are found at the link and network layers. The proposed framework is based on zero knowledge techniques, which are presented through proofs

Layered security design for mobile ad hoc networks

When security of a given network architecture is not properly designed from the beginning, it is difficult to preserve confidentiality, authenticity, integrity and non-repudiation in practical networks. Unlike traditional mobile wireless networks, ad hoc networks rely on individual nodes to keep all the necessary interconnections alive. In this article we investigate the principal security issues for protecting mobile ad hoc networks at the data link and network layers. The security requirements for these two layers are identified and the design criteria for creating secure ad hoc networks using multiple lines of defense against malicious attacks are discussed

Trabeculectomy with Healaflow versus Trabeculectomy for the Treatment of Glaucoma: A Case-Control Study

Purpose. To compare the outcomes of trabeculectomy with and without Healaflow (Anteis S.A, Geneva, Switzerland), a high molecular weight viscoelastic gel, in patients requiring glaucoma surgery. Methods. This was a retrospective, comparative, interventional case-control study. Forty patients formed two matched study groups and were analyzed (trabeculectomy alone (control) versus trabeculectomy with Healaflow (study)). Results. The postoperative levels of mean IOP were statistically significantly lower P<0.05 than preoperatively in both groups, for all time intervals. There was no statistical difference, at the end of the follow-up period, between the two groups in the mean values of the IOP (14.9 ± 3.2 mmHg for the study group versus 14.8 ± 3.3 mmHg for the control group). The number of antiglaucoma drugs used in the study group was reduced from a preoperative mean of 3.4 ± 0.75 to a 6-month postoperative mean of 0.6 ± 0.8 P<0.001 and in the control group from 3.6 ± 0.59 to 0.55 ± 0.9 P<0.001. Conclusions. Although trabeculectomy with Healaflow appears to be a safe procedure, we failed to identify any significant advantages in the use of Healaflow when compared with trabeculectomy alone, at the end of the 6-month follow-up period