H-MAC was proposed to increase efficiency over HMAC by omitting its outer key, and keep the advantage and security of HMAC at the same time. However, as pointed out by the designer, the security of H-MAC also depends on the secrecy of the intermediate value (the equivalent key) of the inner hashing. In this paper, we propose an efficient method to break H-MAC, by using a generalized birthday at...

The attribute access methods of MAC layer in wireless communication network is researched. Aiming at conquering the problem of the shared ZigBee wireless channel resulting multi-channel device conflicts when using the data channel at the same time, therefore the protocol is improved and a method used to access the properties of ZigBee is proposed, and this method can be achieved to manage effec...

Wireless Sensor Networks (WSNs) comprising of tiny, power-constrained nodes are getting very popular due to their potential uses in wide applications like monitoring of environmental conditions, various military and civilian applications. The critical issue in the node is energy consumption since it is operated using battery, therefore its lifetime should be maximized for effective utilization ...

In this paper we provide a method to analytically compute the energy saving provided by the use of transmission power control (TPC) at the MAC layer in wireless sensor networks (WSN). We consider a classical TPC mechanism: data packets are transmitted with the minimum power required to achieve a given packet error probability, whereas the additional MAC control packets are transmitted with the ...

The presence of Mycobacterium avium complex (MAC) in stool specimens may be a predictor of disseminated MAC infection, yet the methods for decontaminating stools have not been evaluated for their usefulness in recovering MAC organisms. In the present study, four decontamination methods commonly used to recover acid-fast bacteria from respiratory specimens were compared for their utility in reco...

Currently, most wireless sensor network applications assume the presence of single-channel Medium Access Control (MAC) protocols. When sensor nodes are densely deployed, single-channel MAC protocols may be inadequate due to the higher demand for the limited bandwidth. To overcome this drawback, we propose multiple channel support for improving the performance. Our method allows the nodes to uti...

An approximate capacity region is established of a class of interfering multiple access channels consisting of two multiple-access channels (MACs), each with an arbitrary number of users, with interference from one of the transmitters of one MAC to the receiver of the other MAC, which we refer to henceforth as the MAC-IC-MAC. It is shown that, for the semi-deterministic MAC-IC-MAC, single-user ...