We study the behavior of algorithms for buffering packets weighted by different levels of Quality of Service (QoS) guarantees in a single queue. Buffer space is limited, and packet loss occurs when the buffer overflows. We describe a modification of the previously proposed “preemptive greedy” algorithm of for buffer management and give an analysis to show that this algorithm achieves a competit...

Wireless Multimedia Sensor Networks (WMSNs) undergo congestion when a link (or a node) becomes overpopulated in terms of incoming packets. In WMSNs this happens especially in upstream nodes where all incoming packets meet and directed to the sink node. Congestion in networks, if not handled properly, might lead to congestion collapse which deteriorates the quality of service (QoS). Therefore, i...

Ad hoc networks are multi-hop wireless networks without a pre-installed infrastructure. Such networks are widely used in military applications and in emergency situations as they permit the establishment of a communication network at very short notice with a very low cost. Video is very sensitive for packet loss and wireless ad-hoc networks are error prone due to node mobility and weak links. H...

Active Queue Management (AQM) plays an important role in the Internet congestion control. It tries to enhance congestion control, and to achieve tradeoff between bottleneck utilization and delay. Random Early Detection (RED) is the most popular active queue management algorithm that has been implemented in the in Internet routers and is trying to supply low delay and low packet loss. RED al...

ODMRP protocol offers a very effective routing mechanism in wireless mobile Ad-hoc networks. But the performance deteriorates when the network is subjected to large amount of traffic. We have proposed a modification in the ODMRP protocol. The congestion in the network is controlled by reducing the RREQ packet retransmission by the source node, managing buffer space. The simulation has been done...

In this paper, we propose the use of a control theoretical approach for a fast and robust fair share computation for a class of fair queueing algorithms based on the Scalable Core (SCORE)/Dynamic Packet State (DPS) architecture. Our proposed approach is generic and can be applied to other SCORE/DPS fair queueing algorithms with little modifications. For purpose of illustration, we applied the L...

We present a method for digital image watermarking based on the modification of certain subsets of the wavelet packet decomposition. These subsets are determined both from a secret key and an image dependent procedure that chooses a best basis from an energy criterion. The mark is set by imposing a parity constraint at each level of the decomposition. We elaborate on the choice of some of the p...

At high transmission speeds, complexity of implementation for fair queuing disciplines can impose a bottleneck to the overall system performance. Available scheduling algorithms set a fixed trade off between fairness and complexity, fairer systems involving more operations per packet and vice versa. In this paper first a new fair queuing scheme is proposed, with almost the same fairness and com...

In 2004, Danezis and Laurie proposed Minx, an encryption protocol and packet format for relay-based anonymity schemes, such as mix networks and onion routing, with simplicity as a primary design goal. Danezis and Laurie argued informally about the security properties of Minx but left open the problem of proving its security. In this paper, we show that there cannot be such a proof by showing th...