Host mobility key management in dynamic secure group communication

The key management has a fundamental role in securing group communications taking place over vast and unprotected networks. It is concerned with the distribution and update of the keying materials whenever any changes occur in the group membership. Wireless mobile environments enable members to move freely within the networks, which causes more difficulty to design efficient and scalable key management protocols. This is partly because both member location dynamic and group membership dynamic must be managed concurrently, which may lead to significant rekeying overhead. This paper presents a hierarchical group key management scheme taking the mobility of members into consideration intended for wireless mobile environments. The proposed scheme supports the mobility of members across wireless mobile environments while remaining in the group session with minimum rekeying transmission overhead. Furthermore, the proposed scheme alleviates 1-affect-n phenomenon, single point of failure, and signaling load caused by moving members at the core network. Simulation results shows that the scheme surpasses other existing efforts in terms of communication overhead and affected members. The security requirements studies also show the backward and forward secrecy is preserved in the proposed scheme even though the members move between areas

Effect of polyethylene cover on the treatment of exposure keratopathy in ICU

Background Exposure keratopathy may lead to serious complications such as microbial keratitis, corneal perforation, and visual impairment if not treated. Aim To compare the effect of carbomer eye drops when used alone and in combination with polyethylene covers in the healing of exposure keratopathy. Methods A single blind randomized-controlled trial (RCT) in two intensive care units (ICUs) was carried out in a university hospital in Western Turkey between September 2011 and December 2012.The control group received only carbomer, eye drops while the intervention group received both carbomer eye drops and polyethylene covers. the primary outcome was the decrease or absence of corneal damage, which refers to healing. Corneal damage was followed up with a fluorescein dye test (decrease/absence of the corneal staining) by the same ophthalmologist for 10 days. Results A total of 43 corneas in 24 patients were studied. Corneal epithelial defects decreased in the intervention group by day 2 and progressed or remained unchanged in the control group every day (P= .001). Patient characteristics did not affect the grade ranges of corneal staining in the groups except for level of consciousness. Conclusion Carbomer eye drops, when used in combination with polyethylene covers, were effective in managing exposure keratopathy. Relevance to clinical practice Corneal damage and further ocular complications can be reduced with the utilization of polyethylene covers in nursing care and treatment.Devlet Planlama Orgutu [05-DPT-003/22]Devlet Planlama Orgutu, Grant/Award Number: 05-DPT-003/2