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 algori...

Event detection is important in many sensor network applications. Traffic in these applications exhibits a many-to-one pattern, in which multiple source nodes send sensing data to a single sink node. Since bandwidth and storage capacity is highly constrained in sensor networks, packet loss is inevitable when a great deal of traffic rushes to sink. Based on the observation that the packets are n...

If highly compressed multimedia streams are transported over packet networks, losses of individual packets can impair the perceptual quality of the received stream in different degrees, depending on the content and context of the lost packet. In this paper, we investigate the impact of individual packet loss on the perceptual speech quality in Voice-over-IP systems using three popular coding ty...

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...

When dealing with packet oriented communications over an ATM network, some problems arise. The most important one is that of having to discard an entire packet when only one ATM cell of that packet has been lost. Thus, we can see that the important parameter in this type of communications is not the Cell Loss Ratio (CLR), but the Packet Loss Ratio (PLR). This paper presents a general and effici...

In a cognitive radio network, a Primary User (PU) may vacate a channel for intermissions of an unknown length. A substantial amount of research has been devoted to minimizing the disturbance a Secondary User (SU) may cause the PU. We take another step and optimize the throughput of an SU, even when assuming that the disturbance to the PU is indeed avoided using those other methods. We suggest n...

Wireless Mesh Networks (WMNs) are going to change fundamentally how communication systems will work in the near future. However, a number of open questions need to be addressed to make this advance possible. This thesis delves into one of these questions: What routing metrics should be used for WMNs in which situation; and how? In this thesis, we investigate the basic mathematical properties an...

Buffers in emerging optical packet routers are expensive resources, and it is expected that they would be able to store at most a few tens of KiloBytes of data in the optical domain. When TCP and real-time (UDP) traffic multiplex at an optical router with such small buffers (less than 50 KiloBytes), we recently showed that UDP packet loss can increase with increasing buffer size. This anomalous...

In this paper, the operation of MPEG-2 systems is modeled and simulated when an MPEG-2 transport stream is delivered through an ATM network with jitter. End-to-end packet-based analysis is performed for delivery of MPEG-2 transport streams over ATM networks. A novel approach to analyzing the decoder buffer behavior in the presence of network jitter is presented. The probability density function...